Astronomy

[Dreamwoven]

I became interested in astronomy in the late 1960s from Thomas S. Kuhn The Structure of Scientific Revolutions (http://en.wikipedia.org/wiki/The_Structure_of_Scientific_Revolutions). This is a theory of scientific revolutions, but it also draws on examples of such revolutions, including the Copernican Revolution (http://en.wikipedia.org/wiki/Copernican_Revolution). Around the same time The Jodrell Bank Observatory (http://en.wikipedia.org/wiki/Jodrell_Bank_Observatory) was in the news, especially the Lovell Telescope (http://en.wikipedia.org/wiki/Lovell_Telescope), using Radio astronomy (http://en.wikipedia.org/wiki/Radio_astronomy). Another event that caught most people's imagination was the first human landing on the moon in 1969, Apollo 11 (http://en.wikipedia.org/wiki/Apollo_11).

Then I left the subject and didn't return to it for many years. Now at last humankind is beginning to explore the solar system with probes being sent to most of the planets. The earliest was Voyager 1 (http://en.wikipedia.org/wiki/Voyager_1) in 1977 which is still operative and recently left the sun's gravitational pull (terminal shock), though this is still debated, and is on its way through outer space, bearing a Golden Record (http://en.wikipedia.org/wiki/Voyager_Golden_Record) in case an alien civilisation finds and can read it. There is, of course, a lot more, including Voyager 2 (http://en.wikipedia.org/wiki/Voyager_2). These also began to map and image the nearer planets their moons and other objects like asteroids and comets, a job that is still incomplete and that the probe New Horizons (http://en.wikipedia.org/wiki/New_Horizons) will soon be doing to do a preliminary mapping of the dwarf planet Pluto. The other major event is the Rosetta Mission (http://en.wikipedia.org/wiki/Rosetta_(spacecraft)) to land on a comet and investigate it.

This is a very exciting time in astronomy, with much happening and much to discuss.

[YesNo]

Most of what I've learned about astronomy was prompted by threads on Lit Net over the past four years that I've been here. It is not that I didn't hear about astronomy topics. I wasn't interested.

For example, until recently, I didn't realize that the Big Bang was the beginning of time and space. I mean, I was shocked, but now I don't see how it could be otherwise.

[Dreamwoven]

I didn't realise there were other threads on astronomy. I did a search and came up with nothing. There are well over 600 threads on serious discussions alone, yet I got no hits. Perhaps I am doing something wrong in my searches...

Anyway, space travel owes a lot to the work of someone I never heard of before - Michael Minovitch and the concept of gravity assist. See this website for details: http://gravityassist.com. Briefly until then rockets were shot up without using the slingshot technique of building up speed by this method, often several times, for example by circling the moon en route to develop enough slingshot speed to reach the goal.

Big Bang (https://en.wikipedia.org/wiki/Big_Bang) is still a theory. I can't even see how it can be proved, but one never knows…

Enormous strides in recent years, and have mapped all the inner planets and their moons with robot probes that do the job without risking human lives by sending people up into space.

[YesNo]

There aren't specific threads, but comments posted that got me thinking and reading stuff on the internet and the local library.

I enjoyed the Minovitch article. He overcame the need for most of the propulsive energy originating from earth to get to the other planets. There is also the radiation issue that has to be taken account of when we leave the magnetosphere of earth. I don't know to what extent that has been solved.

Everything's a theory, but I don't see any reason to doubt the big bang.

[Dreamwoven]

I don't think the radiation danger of humans in space has been addressed. It may be this that will prevent sending humans to Mars.

Yes, it is the abstract nature of understanding the galaxies, Oort cloud (https://en.wikipedia.org/wiki/Oort_cloud), and much else that puts me off trying to grasp even bigger issues like the big bang theory. Right now we have barely begun proper exploration of the solar system in which we live, let alone our home galaxy the Milky Way. The problem with much exploration of space is the abstract nature of the subject.

Yes we have more and more powerful telescopes and even ones in space, like Hubble (https://en.wikipedia.org/wiki/Hubble_Space_Telescope) and what we learn from that is the many exoplanets (https://en.wikipedia.org/wiki/Exoplanet) there going round other suns (stars), and even double stars (https://en.wikipedia.org/wiki/Double_star), with planets that hop between them. There are even rogue planets (https://en.wikipedia.org/wiki/Rogue_planet) that have been expelled from their orbits by some violent space event, still less of their exomoons (https://en.wikipedia.org/wiki/Exomoon). The rate of new knowledge accumulation is very rapid.

Basically, we have not progressed beyond the initial exploration of the solar system we live in. even that is only just at the start. We are about to learn something of the farthest planet we know of, Pluto, if all go well. There are many moons around our neighbouring planets that are quite weird and we still know little about. Perhaps soon probes will be sent to one of these to survey them.

Some space websites:
EarthSky (http://earthsky.org) is a good one that is updated daily. There are many others, see this list (https://en.wikipedia.org/wiki/List_of_astronomy_websites).

[YesNo]

I agree there is a lot to know about our own solar system. I thought we would have known by now from information from the Curiosity rover whether Mars once had life or not, but that is still unknown. There are other places in the solar system to look for life.

Whether one is discussing astronomy or quantum physics one has to separate the facts from the theories which for an outsider (and perhaps even an insider) is not easy to do. The facts are what are going to be there whether the current theories survive or not. For example, one will have the quantum enigmas (based on double-slit-type experiments) to explain whatever quantum theory or interpretation becomes dominant. Similarly, one will have the cosmic background radiation to explain whatever one comes up with for a theory replacing the big bang.

One of the theoretical consequences (not direct facts of the cosmic background radiation) that is derived from the big bang has to do with the actual age of the universe. This is likely based on theoretical assumptions that astronomical constants are actually constant, like the mathematical constant pi, throughout space and time. It probably also assumes that conservation-symmetry laws are valid throughout space and time. If they aren't, how confident would we be in a value like 13.7 billion years for the age of the universe?

Another place where theory can get messed up is through a metaphorical way of looking at the universe. Is the universe more like a deterministic machine or an organism? Was it created or born?

[Dreamwoven]

You are right, of course, and you share an interest in the search for life with many others. SETI, the Search for Extra-terrestrial Intelligence (https://en.wikipedia.org/wiki/Search_for_extraterrestrial_intelligence) is one of the reasons many want to explore outer space.

My reasons are more mundane and to do with discovering our own solar system. We have barely begun that task, and the Voyager series contain the Golden Record (https://en.wikipedia.org/wiki/Voyager_Golden_Record), in the hope of contacting interstellar intelligence.

I have been trying to bring together a very brief overview in this post of the little we do know, and have learned a lot from the Astronomy Now Special Edition on The Planets.

Pluto, discovered only in 1930, is the furthest planet (dwarf planet) from us though there may be others further out. The smaller neighbours of Earth are all rock planets, while the middle ones from Jupiter to Neptune are gas giants with many moons of their own. Jupiter has 64 moons and one of these has its own moon. We have only recently been able to take a closer look at this gas giant since Cassini (https://en.wikipedia.org/wiki/Cassini–Huygens) flew past it. Its main purpose was to study Saturn with its rings and its 62 moons. Cassini was launched in 2000.

There are many exciting probes still to do just to map what we know of our sister planets of the solar system and their almost innumerable moons of ever size, shape and peculiarity.

The last part of your post is itself interesting Another place where theory can get messed up is through a metaphorical way of looking at the universe. Is the universe more like a deterministic machine or an organism? Was it created or born?. I agree this is how to get tied up in metaphysical knots, and would not know how even to begin addressing that.

[YesNo]

I've heard that less is known about our oceans or the life in them than is known about the solar system, but that might be an urban legend.

What do you recommend reading about the solar system?

[Dreamwoven]

The speed of development is so fast just now that I suspect any book on the solar system would be quickly out of date. I'd go for a subscription to a popular astronomy journal, as you are in the USA Astronomy (http://www.astronomy.com) is probably the best. But it is not just about the solar system, like all journals it covers all aspects of space. This website on best popular astronomy books (https://www.google.se/search?q=best+popular+astronomy+books&oq=popular+astronomy+books&gs_l=serp.1.0.0i71l8.0.0.0.8923.1.0.0.1.1.0.0.0..0 .0....0.8..1c..58.serp..0.1.7.0TM2erOkEgs) might be a good place to start.

[YesNo]

I got back from a walk to the library and where I picked up David A. Rothery's "Planets A Very Short Introduction". It was written in 2010, but I am only looking for keywords and other vocabulary.

[Dreamwoven]

I find that much of the advanced astronomy journals are too much into "imaging", as well as the galaxies (I am satisfied with just the solar system and what we can see from in the sky from our homes) and needing advanced telescope and camera equipment. I would love to get more into astronomy but as I am old and infirm it is too difficult to do so (old dogs and new tricks…). In Europe we have more junior journals like Popular Astronomy (http://www.popastro.com/popularastronomy/), both in English and in Swedish (http://www.popast.nu). Perhaps you have an American equivalent...

[YesNo]

There are a lot of sources. I thought you might have one you were interested in reading. I do have binoculars and I've looked at the moon and Venus with them, but basically I don't know what I'm looking at. I think I have spotted Mars and Jupiter, but who knows?

[Dreamwoven]

I'm not sure what you mean by sources? Can you explain?

[Dreamwoven]

A pair of binoculars is what I have, too, 7x50, actually quite good quality, but holding binoculars for any length of time is tiring and quickly starts to wobble. Even a small bottom-end telescope on a tripod is better. But these days observatories are often built in the garden, some are rather basic, like the ones on this website (http://davetrott.com/telescope-projects/beginner-telescopes/). Others are small observatories, more usual owned by a local astronomy club (http://www.skyandtelescope.com/astronomy-clubs-organizations/). I don't have one near me, as we live in a fairly low-population part of Northern Sweden. Nor am I good at making things like that. I'm also in my early 70s so I don't feel able to spend a lot on an interest I acquired late in life.

Many specialise in a planet like Jupiter, or Earth's moon, even the sun, though I would not recommend that as you have to be very careful not to accidentally risk blindness.

[YesNo]

The sources are books or internet articles, basically something to focus our attention on and get the vocabulary.

The link you referred to made me think that maybe I could build my own telescope. I did want to do that as a child, but felt I had to grind the mirror as well. I'll see if I can find Richard Berry's book on making a telescope. The binoculars I have is a 7x50 Nikon Stayfocus Plus II. I don't know it it is any good or not as these things go. I don't look at the Sun through them, but I have seen a solar eclipse through the leaves of a tree. It was amazing. Many eclipsing suns on the ground.

One of the other things I wanted to build was a board to experiment with double slit experiments.

Being in a low population area would mean you can see more stars. I live in a large community outside Chicago, but when I get to Wisconsin and look at the night sky the world is very dark. The night sky stands out.

I think I might try Dave Trott's plan to build a telescope found in one of your links: http://davetrott.com/telescope-projects/how-to-build-the-perfect-telescope/

[Dreamwoven]

That's great, so you are on your way. :)

It is true that light pollution is much less here than Chicago. We also get to see the aurora borealis, especially when there is a period of high sunspot activity. It usually takes the form of "Pillars of Light" (http://apod.nasa.gov/apod/ap131218.html) (this example is from Finland).

I may switch my sub from Astronomy Now to Popular Astronomy the journal that started from the 50's BBC TV programme The Sky at Night (https://en.wikipedia.org/wiki/The_Sky_at_Night), by Patrick Moore (https://en.wikipedia.org/wiki/Patrick_Moore). He was in many ways the one person who brought astronomy to Britain.

[YesNo]

I just hope I get off my butt and do it. I'll be reading the books Trott recommends first, but it looks relatively simple. I should also use the binoculars more to get a better understanding of what is out there. Thanks for the reference!

When I lived in Maine, I remember seeing the aurora borealis wondering what it was the first time I saw it. It wasn't as dramatic as what is in the illustration you provided, but I remember a large portion of the sky shimmered with colors.

[Dreamwoven]

When I lived in Maine, I remember seeing the aurora borealis wondering what it was the first time I saw it. It wasn't as dramatic as what is in the illustration you provided, but I remember a large portion of the sky shimmered with colors.

I've seen similar wonderful examples of northern lights in Scotland. We don't seem to get these displays in Norrland, just the pillars of light. I say "just" but we have been seeing these for several weeks, and they can fill the northern horizon. They usually begin with light on the northern horizon far, far, too early for a false dawn experience. I get up at 5.30 am a good two and a half hours before sunrise at this time of the year (around 8 am).

I've been trying to find out more about this. It does not seem to be the same as Zodiacal light (https://en.wikipedia.org/wiki/Zodiacal_light) which i what Wikipedia classes as False dawn (https://en.wikipedia.org/wiki/False_dawn) in its disambiguation page.

[YesNo]

Going through the trail of links based on zodiacal light, the one on interplanatary dust clouds (https://en.wikipedia.org/wiki/Interplanetary_dust_cloud) was the most unusual. I didn't know this dust even existed nor that it was able to be collected over 60 years ago.

The lights I saw were like the ones in this article except with more red in them: http://www.northernlightscentre.ca/northernlights.html

If was cloudy last night, but I have the binoculars ready. With a book by Patrick Moore, "Stargazing", I hope to eventually be able to identify more than the big dipper.

[Dreamwoven]

Those 2 links were useful, I bookmarked them in my astronomy tab.

The Big Dipper has an informative Wikipedia page that I learned a lot from. It is called The Plough in England and shows how you can find Polaris (https://en.wikipedia.org/wiki/Polaris) using the Plough. Nor was I aware that Polaris is the 45th brightest star in the sky and is in fact a multiple star (https://en.wikipedia.org/wiki/Star_system) involving 3 stars.

This has got me going on using my binoculars to look more at the star patterns. There is a lot more to them than I realised!

[YesNo]

I didn't realize that Polaris was not considered the north star a couple thousand years ago and current distances put it further out than previously thought. I thought those measurements were more accurate than that.

I picked up a recent copy of three astronomy magazines at the library, "Sky at Night", "Sky & Telescope" and "Astronomy". It looks like the European Space Agency's Rosetta has reached it's comet.

[Gilliatt Gurgle]

I didn't realise there were other threads on astronomy. I did a search and came up with nothing. There are well over 600 threads on serious discussions alone, yet I got no hits. Perhaps I am doing something wrong in my searches...

Anyway, space travel owes a lot to the work of someone I never heard of before - Michael Minovitch and the concept of gravity assist. See this website for details: http://gravityassist.com. Briefly until then rockets were shot up without using the slingshot technique of building up speed by this method, often several times, for example by circling the moon en route to develop enough slingshot speed to reach the goal.

Big Bang (https://en.wikipedia.org/wiki/Big_Bang) is still a theory. I can't even see how it can be proved, but one never knows…

Enormous strides in recent years, and have mapped all the inner planets and their moons with robot probes that do the job without risking human lives by sending people up into space.

Hello Dreamwoven, I hold an amateur interest in astronomy, in fact I earned the astronomy merit badge by George! haha.
Anyhow, I'm just now discovering your thread and catching up. The missus and I are about to head out for a dinner, but I'll mention quickly that there are a few related threads I started in the past, simple announcements for the most part, such as "blue moon" and "super moon" events, I mentioned the recent Voyager accomplishment.
And yes; if you create an imaginary line across the two end stars in the big dipper's (part of Canis Major) pot, it will lead you to Polaris.
Here's another nifty trick; if you follow the arc in the big dipper's handle, it will lead you to Arcturus. Follow the "arc to Arcturus". If I recall Arcturus is the major star in the constellation Bootes.
Hello YesNo, not surprised to see you here.

[YesNo]

I am very ignorant about the constellations. I do recognize Venus and I think that might have been Mercury sometimes near by. I think I saw the red Mars and the bright Jupiter all along the ecliptic. Basically, I don't look enough.

Patrick Moore (Stargazing: Astronomy Without a Telescope) had this to say about professional astronomers probably to give people like me encouragement: "Strange though it may seem, I know a number of eminent professionals who would be quite unable to go out on a clear night and identify the various star-groups!"

[Dreamwoven]

I didn't realize that Polaris was not considered the north star a couple thousand years ago and current distances put it further out than previously thought. I thought those measurements were more accurate than that.


I picked up a recent copy of three astronomy magazines at the library, "Sky at Night", "Sky & Telescope" and "Astronomy". It looks like the European Space Agency's Rosetta has reached it's comet.

Its not really about accuracy, but reflects the phenomena known as Precession (https://en.wikipedia.org/wiki/Precession). That is why in the musical "the age of aquarius", refers to the star sign of that name. Though I have no idea if it bears any relationship to precession, somehow I doubt it.

I'e never heard of the Sky at Night magazine. It is probably too expensive to subscribe to it outside the UK. But I'll go for Popular Astronomy in any case.

[Dreamwoven]

Hello Dreamwoven, I hold an amateur interest in astronomy, in fact I earned the astronomy merit badge by George! haha.
Anyhow, I'm just now discovering your thread and catching up. The missus and I are about to head out for a dinner, but I'll mention quickly that there are a few related threads I started in the past, simple announcements for the most part, such as "blue moon" and "super moon" events, I mentioned the recent Voyager accomplishment.
And yes; if you create an imaginary line across the two end stars in the big dipper's (part of Canis Major) pot, it will lead you to Polaris.
Here's another nifty trick; if you follow the arc in the big dipper's handle, it will lead you to Arcturus. Follow the "arc to Arcturus". If I recall Arcturus is the major star in the constellation Bootes.
Hello YesNo, not surprised to see you here.

Welcome to the thread! I must try to search for those threads using the search function.

[Dreamwoven]

I am very ignorant about the constellations. I do recognize Venus and I think that might have been Mercury sometimes near by. I think I saw the red Mars and the bright Jupiter all along the ecliptic. Basically, I don't look enough.

Patrick Moore (Stargazing: Astronomy Without a Telescope) had this to say about professional astronomers probably to give people like me encouragement: "Strange though it may seem, I know a number of eminent professionals who would be quite unable to go out on a clear night and identify the various star-groups!"

One thing I'e learned from this thread is to use my binoculars more. November is a bad time of the year for sky-watching as its so often heavily overcast and rainy. Once the snow comes the skies clear at night, much easier.

I thought to see how the Rosetta Mission goes and then starting a thread on it. Very ambitious and looks to be highly problematic because it ended up in a poor location for sun to recharge the batteries, and the anchors failed…We will see how things pan out.

[Dreamwoven]

The emphasis seems to have shifted from observing to taking pictures. I can never work out which contraptions on a telescope are for clearer, further, wider-field observing and which are for taking photos. It is almost as if taking photos have become more important than observing, probably because of the internet and the opportunities for publicly "displaying" photos using Photobucket (https://en.wikipedia.org/wiki/Photobucket) and other websites.

Many blogs seem to be devoted to this. It is, of course, very impressive to be able to see well-taken photos of planets and moons, just because of its beauty. But taking pictures now is determined by digitalisation, and has changed out of all recognition from the days of the black-and-white snapshots of the box camera (https://en.wikipedia.org/wiki/Box_camera) in the 1950s and 1960s. "Imaging" (https://en.wikipedia.org/wiki/Imaging) is quite appropriate as we are not taking photos in the traditional sense, so we talk about "to image" something: a new verb for me.

The trouble is that it is also less natural, more manufactured, using multi-spectral imaging (https://en.wikipedia.org/wiki/Multispectral_image) and false-colour (https://en.wikipedia.org/wiki/False_color). I only learned about this recently and it has made me much less certain of what exactly it is I am seeing! I guess this is something everyone has to learn.

[YesNo]

If one is taking a photo of frequencies that one cannot normally see, then some sort of false coloring makes sense to make the image visible. I guess the pseudocolor techniques are justified for similar reasons even when one can see the image. It just makes evident distinctions that are not as clear with true color. It is deceptive unless one is informed that such techniques were used. I tend to assume what I see is in true color, but it probably isn't.

On another topic, I recently heard that the moon was not round, but shaped more like a lemon. I wouldn't expect it to be exactly round in any case, but the image I saw in one of the astronomy magazines had it looking more like an American football rather than a soccer ball. I wonder to what extent that image was manufactured and inaccurate.

[Dreamwoven]

I think you are referring to a Gibbous Moon (http://www.universetoday.com/20324/gibbous-moon/), which does look a bit like a rugby ball. The website link above explains it quite well. But I still find to hard to grasp sometimes. Some moons are also misshapen and look that way, irrespective of the light source.

[YesNo]

The gibbous moon is just the shape of the lighted portion. This is supposed to be the actual shape of the moon including the dark part. It looks round to us because the moon always shows the same face to us. If looked at it from the side, it would, supposedly appear more elongated, but I suspect the photo I saw in the magazine might have been exaggerated.

Here's one article with the moon only slightly deviating from a round shape: http://www.space.com/26684-moon-lemon-shape-tidal-forces.html

Here's a video with the shape the way I saw it in the magazine: https://www.youtube.com/watch?v=tZvnrCjuY2I

[Dreamwoven]

I suspect there is no clear answer as to why the moon has the shape it does, just different theories. I would just use Gibbous to describe the moon lit from underneath and the illusion that results in.

[NikolaiI]

I have always liked astronomy, but never caught the fever for it. My dad had a decent telescope at one point when we were kids, and we lived in the country which made it better for looking at the stars. I got to see Saturn and the Moon and some other things... I loved it but it never interested me as much as the other sciences. Space travel, which is probably one of the most important things we can do, is very dependent on it though, so for that reason I would always support it.

[YesNo]

So far it has been too cloudy to take the binoculars outside. I think I should be able to see Mars in the west after the sun sets.

[NikolaiI]

What's your favorite celestial body to view?

[Dreamwoven]

The moon has been mine, if only because I don't have a telescope or a nearby astro club to join.

I look forward to being able to see the clear sky, never mind the heavily overcast cloud we have had for most of November, as soon as clear skies appear I will be looking. YesNo, what can you see of Mars with binoculars?

[Calidore]

I suspect there is no clear answer as to why the moon has the shape it does, just different theories. I would just use Gibbous to describe the moon lit from underneath and the illusion that results in.

The prevailing theory, which is both simple and makes sense, is that 1) the molten moon was splooshed from the new, still-molten Earth when a Mars-sized body impacted it several billion years ago, and 2) the tidal forces from Earth's gravity slightly distorted the molten moon into its current shape, which became permanent when it cooled.

[108 fountains]

I'm sorry to admit that I've never looked through a telescope, but I have seen the nighttime sky from a mountainside in Nepal - there was nothing like it.

[NikolaiI]

That's wonderful. I would love to as well... I lived 10 miles out in the country so there was less light pollution, but from what I understand there's still a world of difference if you can get to a place very far from cities.

[Dreamwoven]

That's wonderful. I would love to as well... I lived 10 miles out in the country so there was less light pollution, but from what I understand there's still a world of difference if you can get to a place very far from cities.

Ah, but what counts as very far? There are several towns just 10 km from us, even though we are in a rather isolated part of Sweden.

At the same time I am sure that 108 fountains can see a lot more in Nepal than from other places in crossed Europe: must be wonderful!

[NikolaiI]

Well, the antarctic cricle would qualify :)

Also I am sure it depends on how large the cities are... 10 miles away from a town of 500 would be nice, but 10 miles from Las Vegas probably wouldn't be that great.

[108 fountains]

I was at about 10,000 feet (3000 m); not sure if that elevation is significant enough to make a difference, but I remember it being clearer and more three dimensional than the time I was out on a boat on the Mediterranean and also had a great view of the sky at night.

[Dreamwoven]

I am sure being at 10,000 feet would make a difference - a big one.Sounds like an experience of a lifetime!

[YesNo]

The moon has been mine, if only because I don't have a telescope or a nearby astro club to join.

I look forward to being able to see the clear sky, never mind the heavily overcast cloud we have had for most of November, as soon as clear skies appear I will be looking. YesNo, what can you see of Mars with binoculars?

I don't know. I suspect just a red dot of light, but so far it has been too cloudy (or I forgot to look on the clear days). The moon has something more interesting to look at.

I understand you can see the moons of Jupiter with binoculars, but I would have to find out where Jupiter is in the sky first.

[Dreamwoven]

I use the British Popular Astronomy website to locate the when and where of planets.

Jupiter
A Selection of Section Members Images are reproduced below together with occassional notes from me:

The new Jupiter observing 'season' has barely started with Jupiter still a very early morning object in November 2014; but it will rapidly become more accesible and new images will be posted here soon. In the mean time the last Jupiter apparition produced a wealth of interesting features that were observed and imaged by SPA members. Here are a few from February and March this year.

Transiting moons can be seen as a shadow on Jupiter, as the website (http://www.popastro.com/planetary/observations/observation.php?id_secRep=69) shows. I have seen them with a friend's telescope showing them on either side of Jupiter (there are over 60 moons of Jupiter) - an unforgettable sight.

But I hope to be able to see more with my binoculars under good conditions.

[NikolaiI]

Does Astronomy engender a desire to go to these places for any of you? I can truthfully say the desire has never left me.

[Dreamwoven]

What places do you mean? The moon, Jupiter, Mars? They are all very inhospitable...

[NikolaiI]

Yep, yep, or further. I remember when I was young, my dad explaining why Jupiter couldn't be visited... how the gravity is so great it would crush anyone before they could ever reach the surface, and how the planet itself wasn't solid, but gaseous... Being told something is impossible sometimes serves to ignite one's imagination to try to figure out how it could be possible.

But your answer sound rather like a no. Which is fine, I was just wondering.

And of course, I know it is somewhat impractical to think of personally going to space for the experience of it, but that doesn't mean that with effort it's not possible to eventually do more of that kind of thing.

[YesNo]

The evening was clear enough to watch the moon set through the trees. I couldn't see any craters on the moon, but the dark trees against the bright moon and a house nearby was nice. Next time, I'll try to use my phone to take a picture through the binoculars. I'd do it now, but the moon has already set.

Edit: I tried taking a picture with my phone's camera through one eyepiece of the binoculars inside. It does work, but the results are grainy. Also, I can get 4X zoom on the phone and the binoculars are only 7X. I might as well take the picture without them.

[108 fountains]

If you have a good camera with lots of pixels per area of measurement, you'd be surprised how much you can magnify something once you download the photo to your computer, although I've never tried it with anything like the moon.

[Calidore]

What places do you mean? The moon, Jupiter, Mars? They are all very inhospitable...

Until we sent probes to Venus in the '60s and found out what it was really like, sci-fi writers liked to portray it as a habitable jungle planet.

[Dreamwoven]

Calidore: that does show how far our knowledge has developed even in our own lifetime.

108 fountains and YesNo: I don't have a mobile phone at all, but it must open up a lot of possibilities to try thing like that, especially with a phone that can magnify pictures x 4.

We are still exploring our own solar system, there is so much to learn. How many moons are there around the planets we know of and we have only recently begun to study a fraction of them from fly-bys. I think it is all very exciting.

[Calidore]

Agreed. When I was a kid, Jupiter had nine or ten moons; now it has dozens.

[Gilliatt Gurgle]

I remember the first time catching Jupiter in my telescope as a kid. the telescope was a was a refractor (100 power?) strong enough to allow me to see about 5 of the largest moons, then it was on to Saturn. I was thrilled.
Binoculars are great for star clusters such as the Pleiades.

[Dreamwoven]

There is an interesting article published today in Space.com on Neptune: http://www.space.com/41-neptune-the-other-blue-planet-in-our-solar-system.html?cmpid=558609

Our knowledge of the outer planets, Saturn, Neptune, Uranus and Pluto and their moons, is still very sketchy.

[Dreamwoven]

One of the astronomy websites I subscribe to is www.earth sky.org (http://www.earthsky.org). A new post has been put up concerning young volcanos on the moon (http://earthsky.org/space/video-young-volcanoes-on-the-moon?utm_source=EarthSky+News&utm_campaign=49464496dd-EarthSky_News&utm_medium=email&utm_term=0_c643945d79-49464496dd-394044013).

They are apparently more common than was first thought, suggesting that the moon is not dead and volcanic activity continues.

[NikolaiI]

So no interest whatsoever in space travel?

[YesNo]

I was hoping to get a picture of the crescent moon like the the one in the earth.sky link, but it was too cloudy. I could see last night the crescent through the leafless trees by a house across the street. I might even get a glimpse of Mars. I would need the binoculars to see this, but maybe not.

The young volcanos video was interesting. I remember being told that the moon was dead, but that may not be true.

The note by Deborah Byrd that there is an "invisible shield" at the outer edge of the Van Allen radiation belt was also interesting. I wonder if this is considered part of the magnetosphere which protects us from radiation or something different.

[Dreamwoven]

So no interest whatsoever in space travel?

Do you mean me personally. I am too old and unwell to even think about it.

Of course, I would be interested to see it happen, but there is none at present. I guess that all emphasis is now on robot data collection on Mars, Moon and with fly-pass cameras, as well as more advanced telescope exploration further afield.

[Dreamwoven]

The note by Deborah Byrd that there is an "invisible shield" at the outer edge of the Van Allen radiation belt was also interesting. I wonder if this is considered part of the magnetosphere which protects us from radiation or something different.

You got me there, I have no idea!

[NikolaiI]

You've inspired me to get back into it, Dream. I was reading some Neil DeGrasse Tyson articles today and it was very enjoyable... I highly recommend them, they're incredibly good. This (http://www.google.com/url?url=http://www.haydenplanetarium.org/tyson/&rct=j&frm=1&q=&esrc=s&sa=U&ei=98h3VJXUNfHhsASa0oGYBw&ved=0CBQQFjAA&sig2=Cpn6_9iIxilMxKgYwtbnbA&usg=AFQjCNEP8Iq8McPVilOl87xgt7Cd67rpMw
) appears to be a good place to find them. So far I've just read two from the Natural History magazine, Spacecraft Behaving Badly and Delusions of Space Enthusiasts.. The first was very interesting and informative, I'm very curious to know about the follow-ups, and the latter was just extremely good all around. These were both here (http://www.haydenplanetarium.org/tyson/tags/media/natural-history-magazine).

I liked this-


Having been born the same week NASA was founded, I was eleven years old during the voyage of Apollo 11, and had already identified the universe as my life's passion. Unlike so many other people who watched Neil Armstrong's first steps on the Moon, I wasn't jubilant. I was simply relieved that someone was finally exploring another world. To me, Apollo 11 was clearly the beginning of an era.

And the last paragraph has a beautifully good point.

[Dreamwoven]

Tyson is the guy who has the TV programme on space. He was a colleague or student of Carl Sagan (https://en.wikipedia.org/wiki/Carl_Sagan). The first post (Spacecraft behaving Badly) (http://www.haydenplanetarium.org/tyson/read/2008/04/01/spacecraft-behaving-badly) is fascinating. I look forward to reading more. It argues that Newton's theory of gravity which is one of the taken-for-granted "facts" of space travel doesn't apply once the crafts (in this case Pioneer I and II) leave the solar system.

[YesNo]

Tyson's article interested me in questioning Newton's laws of gravity beyond 15 AU from the sun where Einstein's modifications were no longer relevant. Also, if Newton's laws of gravity are the problem what does that do to the supposed existence of dark matter and energy? I thought those were based upon missing matter and energy assuming Newton's laws were correct.

I wonder if there is information about this from Voyager 1? http://en.wikipedia.org/wiki/Voyager_1

[Dreamwoven]

Yes, I wondered about that, too. I've re-read the voyager 1 link you provided, and I am still confused. There is no mention of drifting similar to Pioneer, but a lot of other stuff like passing the heliopause, termination shock, and passed the heliosheath and both V1 and V2 are now in interstellar space. heading towards other galaxies. Taking 300 years to reach the Oort Cloud where comets are born, and take 30,000 (!) years to pass through it.

Perhaps they don't know where the probes are with any accuracy to show that there has been or has not been any drift.

The whole thing is just too mind-boggling to understand.

[YesNo]

Your initial link got me thinking about dark matter/energy and it looks like there are people questioning whether the evidence that seems to call for the existence of dark matter is really evidence that the laws of gravity are not as simple as we assumed. http://en.wikipedia.org/wiki/Dark_matter

I was looking for the crescent moon I saw a couple days ago and realized that things change quickly. The moon has lost that lovely crescent shape. I will have to wait until next month to get the photo, if the skies are clear and I don't forget.

I also read that in the first weeks of January Venus and Mercury will be in conjunction, that is, they will set at the same time.

[Dreamwoven]

As I understand Dark Matter it is light travelling away from the viewer at a speed faster than light, being sucked into a hole. But it is very theoretical, much like Schrödinger's Cat (https://en.wikipedia.org/wiki/Schrödinger's_cat), a concept that, however much I try to grasp, eludes my understanding.

Yes, astronomy can be very frustrating. Here we have had blue skies during the day but it clouds over by dusk or even earlier, and it has been like this for a week or more, staying cloudy until it is light and the stars can't be seen. I still have not managed to use my binoculars as I had hoped...

[NikolaiI]

I just found an extensive and very interesting Wikipedia article (http://en.wikipedia.org/wiki/Pioneer_anomaly) on it, and it reports that they solved the question with fair certainty in 2012. I find it fasinating how much interest there was in it, and the different proposed explanations. Tyson's article builds suspense very well.. With all of the factors involved, all of the different temperatures, instruments, and everything else, it took them until 2012 to account for the anomaly completely.

It appears a certain amount of the article was written before the issue was settled, so some of the parts about possible explanations are a history of it, for example:


The asymmetrical radiation of heat remains a prime suspect, as presented at the second ISSI meeting in Bern, February 2007. A presentation at the APS April 2008 meeting suggests that differential heating may account for as much as one third of the observed acceleration.[39]

Yesterday my best guess was drag - dust and what not, but nope.


Drag
The cause could be drag from the interplanetary medium, including dust, solar wind and cosmic rays. However, the measured densities are too small to cause the effect.

and another one, what you mentioned Dream-


Observational or recording errors
The possibility of observational errors, which include measurement and computational errors, has been advanced as a reason for interpreting the data as an anomaly. Hence, this would result in approximation and statistical errors. However, further analysis has determined that significant errors are not likely because seven independent analyses have shown the existence of the Pioneer anomaly as of March 2010.[43]

The effect is so small that it could be a statistical anomaly caused by differences in the way data were collected over the lifetime of the probes. Numerous changes were made over this period, including changes in the receiving instruments, reception sites, data recording systems and recording formats.[9]


Meetings were held...


A meeting was held at the University of Bremen in 2004 to discuss the Pioneer anomaly.[61]

The Pioneer Explorer Collaboration was formed to study the Pioneer Anomaly and has hosted three meetings (2005, 2007, and 2008) at International Space Science Institute in Bern, Switzerland to discuss the anomaly, and discuss possible means for resolving the source.[62]

[Dreamwoven]

Nikolai, that was very interesting, after just a quick read. I didn't think to search in Wiki for it. I need to read this a couple more times to digest it properly.

[YesNo]

That article on the Pioneer anomaly, http://en.wikipedia.org/wiki/Pioneer_anomaly, made me wonder even more about dark matter. Here is the part about gravitation that caught my attention:


It is possible that deceleration is caused by gravitational forces from unidentified sources such as the Kuiper belt or dark matter. However, this acceleration does not show up in the orbits of the outer planets, so any generic gravitational answer would need to violate the equivalence principle (see modified inertia below). Likewise, the anomaly does not appear in the orbits of Neptune's moons, challenging the possibility that the Pioneer anomaly may be an unconventional gravitational phenomenon based on range from the Sun.

If there is no anomaly in Neptune's moons, then there is no need for dark matter to make those orbits perform as predicted. Does that mean there is no dark matter in our solar system?

[NikolaiI]

I am not sure, YesNo.

[YesNo]

I started looking around the internet and apparently this problem has already been raised: http://www.technologyreview.com/view/516681/the-incredible-dark-matter-mystery-why-astronomers-say-it-is-missing-in-action/ It looks like there isn't much of any dark matter in the solar system, but apparently on a large scale it is needed to make the gravitational laws work.

Either the gravitational laws are accurate but the calculation of the amount of visible mass is off by a factor of 5 to 10 or so or the gravitational laws are more complicated than originally believed. Perhaps both. Of course, perhaps there is dark matter out there.

Edit: I just thought of something that I remember reading from Rupert Sheldrake's books. Newton's law of gravity F = G*(m1*m2/r^2) may have a problem because G ("big G") may not be a constant. When we are looking at galaxies we are seeing them as they were in the past and big G may have been different then. Here are the recent results of trying to calculate big G: http://www.scientificamerican.com/article/puzzling-measurement-of-big-g-gravitational-constant-ignites-debate-slide-show/

If the value of big G is dependent upon time then one should be able to see galaxies with certain mass behaving differently but similarly for those the same distance from us. That would be one way to test and possibly falsify the conjecture that big G changes with time.

Edit 2: Although the day was bright and warm with a clear sky, the evening sky is covered with clouds.

[Dreamwoven]

Edit 2: Although the day was bright and warm with a clear sky, the evening sky is covered with clouds.

YesNo: did the end of this get cut off unfinished? I might have said something along these lines re my frustration over conditions when I can use my binoculars. Or is it nothing to do with that?

[YesNo]

Yes, I wanted to say that I was having the same problem you were having. Yesterday I expected the sky to be clear because it was a nice warm day with few clouds. I could even see the moon half illuminated as I walked through the forest preserve and got some pictures of it with my phone through the trees. That was around 2 pm. Toward evening the clouds came in, just as you described.

[Dreamwoven]

I guess one of the things I am learning is patience. Not easy trying to try out new equipment.

[NikolaiI]

When I was a young child I used to like to tell people, "Patience is a virtue, and virtue is its own reward, so we should all just sit and wait for that reward to come." But all kidding aside, anticipation can heighten pleasure :) It will be that much prettier when you can use it on a clear night.

[YesNo]

I'm still practicing patience since last night was cloudy again, but I think Wednesday may be just right. I don't know what I'm looking to see, perhaps just to convince myself that the constellations in Patrick Moore's book are really out there.

I also searched for dark energy and dark matter. It seems they are ad hoc solutions to two different problems. Dark matter attempts to explain why spiral galaxies do not fall apart and dark energy tries to explain why the universe is expanding. They do fit the solutions to the current problems perfectly as seen from the cosmic microwave background, but that is what an ad hoc solution is supposed to do. Since there is no need for dark matter in our solar system and the Andromeda galaxy is heading toward us, not away, they make me wonder.

In my wanderings in the internet forest, I found a blogger, Miles Mathis, who doesn't like this dark stuff either. He reminded me of Eliezer Yudkowsky who believes in many worlds. They are both very literate, that is, they are both likely to convince me if I don't watch out. I wonder if I'll be disagreeing with Mathis as much as Yudkowsky the more I read him.

[Dreamwoven]

I guess overcast skies will mean you will beat me to the starting line. November went out with a record in the Stockholm area for a grey November, with just 5 hours of sun in the entire month (http://www.thelocal.se/20141130/north-enjoys-record-sun-as-capital-goes-grey). Nights have been the same, grey skies making for nil space observing. And here in Southern Norrland its been especially bad.

I have been exploring your links to various issues, the two people you mention and dark energy and dark matter (http://science.nasa.gov/astrophysics/focus-areas/what-is-dark-energy/). I feel a bit of a fool, I didn't realise NASA had such an extensive website, so I have begun to investigate it. It's a mine of information.

[YesNo]

Another cloudy night. Five hours of sunshine seems like too few.

In trying to sort through the dark stuff, I found a book, "In Search of Dark Matter", by Ken Freeman and Geoff McNamara in the library. They are true believers in dark matter even though they claim that the disk of the Milky Way is "more or less free of dark matter".

The NASA link you referenced has this: "The first property that Einstein discovered is that it is possible for more space to come into existence." If more space can come into existence, perhaps more matter-energy can come into existence as well. Maybe it didn't all have to be compressed together just before the big bang.

[Dreamwoven]

Or maybe there is not just one unique universe. We alway used to think our sun was unique, never realising that the countless stars in the sky are also suns. Shock, horror: they are indeed! Nor is our planet earth so unique. It seems the universe has countless billions of them. And what if our universe is also just one of many? We have not "found" any others, of course, but exploring "our" universe is still only a pipe dream. The mind boggles at the immenseness of this our universe, just like our foremothers' minds boggle at thinking our sun was not unique.

[YesNo]

It occurred to me last weekend that the morning sky might be clearer than the evening sky. That means I will have to get up earlier so there is time to look. Also I am about a 15-minute drive from a park on Lake Michigan where I could see the sun rise, but I have never done so. It is always the setting sun that is in my mind.

I think you are right about our universe not being unique. If it had a beginning, other universes probably had beginnings as well. That means there is an "outside" to our universe and the space and time we experience within our universe is separate from it.

[Dreamwoven]

I've been trying to find out what optical telescopes (as distinct from radio telescopes, used to pick up signals like SETI) there are that can be used for visually exploring space. This is a list (https://en.wikipedia.org/wiki/List_of_largest_optical_telescopes_historically). Its a very complex issue, more so than I bargained for.

I've also been exploring the NASA website. There is a project called Orion (http://www.nasa.gov/exploration/systems/mpcv/index.html#.VH3Vst4R5O0) which in several stages will send humans into space, perhaps ultimately onto Mars. But I doubt if I'll see any results, in 2021 I will be 69 but that is planned as the first flight with humans on board, and all it will do is go in orbit round Earth (if it gets that far!). there are no concrete plans for flights beyond this, not yet anyway. That may come in later stages.

I can't really see the point, as there are already several wheeled robots on Mars collecting data, rock samples and carrying out mapping.

There are many other projects covering a wide range of types of goals, a vast list of them in alphabetic order.

[YesNo]

I'll be 70 in 2021. It looks like we're both over some hill.

That Orion mission puzzles me as well. If all we will be able to do fifty years after going to the moon multiple times is set humans in orbit around the earth, well, it makes me wonder.

[Dreamwoven]

Orion is intended to develop well beyond 2021, ultimately leading to astronauts on Mars. But I think putting a man on the moon was a political issue, after sputnik 1 (https://en.wikipedia.org/wiki/Sputnik_1), Laika (https://en.wikipedia.org/wiki/Laika), the first dog in space and Yuri Gagarin (https://en.wikipedia.org/wiki/Yuri_Gagarin), the first man in space. Yuri Gagarin visited Britain in 1961, I remember in the summer before going to university seeing him at Earls Court in London (see http://www.bbc.co.uk/news/science-environment-12993533). It was the time of the Cold War, the US felt the Soviets had stolen a march on them and the first astronaut on the moon in 1969 was a way of redressing the balance.

[YesNo]

Nice article about Yuri Gagarin. I can see why he would be so popular, but I didn't know of that event.

I still haven't had a chance to look for the constellations. I forget when the opportunity is right or get busy with something else.

[Dreamwoven]

Nice article about Yuri Gagarin. I can see why he would be so popular, but I didn't know of that event.

I still haven't had a chance to look for the constellations. I forget when the opportunity is right or get busy with something else.

I've also to do some sky-watching with my binoculars. It is very cold to be standing outside, even well-wrapped. I'll have to look for a dark night sky towards spring.

I now have a bit more news on Project Orion. The 2021 end point is only for the first stage. Work needs to be done on the accommodation section of the module, to create and test it, I guess. So there is a long way to go to the astronaut flight to Mars, if it ever happens.

[YesNo]

They should probably go back to the moon as a test before going to Mars. There are people who think we didn't go there in the first place, at least, not with manned missions.

[Dreamwoven]

I've checked up about the moon, there is Wikipedia posts on the Great Moon Hoax, meaning that in 1835: here (http://en.wikipedia.org/wiki/Great_Moon_Hoax). NASA (http://science.nasa.gov/science-news/science-at-nasa/2001/ast23feb_2/) has also come out with a denial. As far as I remember the race between the USSR and USA to get to the moon first was what lay behind the modern version. Moon rock was brought back by a later Apollo and I think by the Soviets eventually.

I don't think there is any doubt but the sort of story was stimulated by the competition itself.

Project Orion has no dates set for the Mars visit, and anyway it will be long after I will be around. The next major task is to create a human service module. Still can't see the point, unless there is something there like vast mineral wealth (iron?) to be won:but at what cost in human life? Mars is now crawling with mechanical samplers and even a satellite (artificial moon), measuring and examining.

[YesNo]

I didn't know about 19th century moon hoaxes. I remember reading something about Herschel believing there were people on the other planets of the solar system, but now I will have to be careful. He probably didn't believe such things.

When I first heard about the Apollo hoax a couple years ago, I remember being skeptical about it for the first day and then wondering the second and being left with a sense that it could have all been a TV show I watched as a child. I don't see the point in humans going to these other planets either. We should show our technical abilities by making AI that can do that for us.

[Dreamwoven]

Good chance to see comet Lovejoy : http://www.eagleseye.me.uk/Sky/Wordpress/?p=3503
Comet Lovejoy C/2014 Q2 is heading northwards. Currently located in the constellation pf Puppis, it is heading towards Columba and Lepus.By the 22nd of the month it should just about be visible from the UK. Currently estimated at just under 6th magnitude, it is almost a naked eye comet already, and should get brighter.

[YesNo]

I was able to find Orion a couple days ago and identified Aldebaran and the Pleiades in Taurus. Lepus is just below Orion, so hopefully, I'll be able to see that comet.

[Dreamwoven]

Hope you do. My health is not good enough to be outside with binoculars on a cold night. You may also see the Geminid meteor shower (http://earthsky.org/space/everything-you-need-to-know-geminid-meteor-shower), a good one this year it seems.

[YesNo]

It is too cloudy to see much tonight, but I find Gemini near Taurus and Orion on an atlas so I should be able to pick out the constellation later. The photos were nice in the link.

[Dreamwoven]

New Horizons has been woken out of hibernation and working again, ready to pass Pluto. It can be tracked here: http://pluto.jhuapl.edu/mission/whereis_nh.php, scroll down for the two perspectives on this coming flyby. Full Trajectory Overhead and Full Trajectory (Side view).

[YesNo]

It looks like Pluto is the last planet to be explored and I didn't realize it was a double planet. It will be interesting to see the pictures that come back from New Horizons.

[Dreamwoven]

Yes, as far as we know it is the last and also the least explored. In 2006 it was re-classified as a Dwarf Planet (http://www.space.com/43-pluto-the-ninth-planet-that-was-a-dwarf.html), a denizen of the distant Kuiper Belt (http://solarsystem.nasa.gov/planets/profile.cfm?Object=KBOs).

There is still controversy over Pluto's status and presumably also of Charon (http://en.wikipedia.org/wiki/Charon_(moon)), almost as big as Pluto,yet also its moon. If a dwarf planet can have another dwarf planet of similar size as a moon circling around it.

At this distance from the sun it doesn't take a large mass in the Kuiper Belt to be held in orbit round the sun and also as a "moon" of another small planet/dwarf planet, together as a double (dwarf?) planet.

The last planet to be explored makes Far Horizons especially interesting.

I've used NASA's website on Solar System Exploration (http://solarsystem.nasa.gov/index.cfm) for much of what I have learned of Pluto and the other dwarf planets.

What do you make of all this?

[YesNo]

I found the idea of "tidal locking" interesting. Pluto and Charon face each other with Charon's orbit taking the same time as Pluto's rotation.

I thought those scientists agreed to call it something other than a planet. I understand from the link that Pluto is a dwarf planet because it has not "cleared the neighborhood" in its orbit of other objects such as those in the Kuiper belt. However, since Pluto crosses Neptune's orbit does that mean Neptune has not cleared the objects in its neighborhood?

[Dreamwoven]

So far away from the sun, on the edge of the Kuiper belt, the gravity of the sun is much weaker while the gravity of planets, dwarf planets, comets and asteroids are commensurately enhanced. What you write about the orbit of Pluto crossing the orbit of Neptune, I guess in longer time spans it is possible that the two bodies might be at risk of collision, though this is not, I understand, likely for many centuries.

The orbit of Pluto is angled differently from the other planets, so it crossed the track of all the planets as a result. Uranus is also a possible collision course, though again not for a very long time. The second of the two perspective diagrams of New horizons route (http://pluto.jhuapl.edu/mission/whereis_nh.php) makes this clear.

[Dreamwoven]

The Winter Solstice is the time to watch the Ursid Meteors, as EarthSky (http://earthsky.org/space/ursid-meteor-shower-active-around-winter-solstice) have explained. Meteors display at radiant points. There is a full catalogue of meteor showers at http://earthsky.org/astronomy-essentials/earthskys-meteor-shower-guide.

I have to confess I have never seen a meteor shower, you may need to camp out in the night under the starts in a sleeping bag to keep warm. Can't do it in midwinter, not here in Northern Sweden. Much the same goes for comets, though being larger and more visible can be a more visually dramatic experience. See http://www.popastro.com/comet/findercharts/index.php

[YesNo]

I have seen a few scattered meteors but never a shower of them. Comets are at least more permanent. I have seen a handful of those. There was one more than 15 years ago that was very visible. I remember carrying my daughter out onto the patio and showing it to her. I pointed to it, but I wonder if she realized what I was pointing to.

[Dreamwoven]

The one you saw in the mid-1980s was probably Halley (http://cometography.com/pcomets/001p.html). I saw that too, during a stay at the Bålsta Anthroposophy Village in Sweden. It was the most striking comet I have ever seen (though that's not saying much) Cometography.com (http://cometography.com) Cometography is run and maintained by Gary W. Cronk (http://en.wikipedia.org/wiki/Gary_W._Kronk) and is remarkably comprehensive. I may make comets one of my special interests.

[YesNo]

That was a very detailed comet cite. I will try to see C/2014 Q2 (Lovejoy) which binoculars should make available if the sky is dark enough. I haven't had many evenings when stars were visible.

I think the comet I saw was Hale-Bopp: http://en.wikipedia.org/wiki/Comet_Hale%E2%80%93Bopp. In 1995 my daughter would have been about the right size to carry her onto the deck.

[Dreamwoven]

You are almost certainly right. Hale-Bopp it was, not Halleys: http://en.wikipedia.org/wiki/Comet_Hale–Bopp

[Dreamwoven]

Space.com has written about NASA's attempt to capture an asteroid and put it in orbit around the Moon (http://www.space.com/28045-nasa-asteroid-mission-decision-2015.html?cmpid=558747). The idea being to study it. Won't be for a few years but should be interesting.

[YesNo]

After all the talk of asteroids coming near enough to crash into Earth, I am surprised they would want to do something like that. But if they can move an asteroid toward the moon, they should be able to deflect one that strays our way.

[Dreamwoven]

I think that is partly behind the idea, but I also thought it was a bit high-handed. I doubt it is big enough to be a problem if it should crash to earth, but some of these space activities probably have a degree of showmanship about them.

[Dreamwoven]

I have just joined Popular Astronomy, which is about my level of astronomy knowledge. It has a forum for a variety of debates. This is one of the shorter items in the electronic news bulletins put up there. Others or extracts from longer ones may follow.

The SOCIETY for POPULAR ASTRONOMY

Electronic News Bulletin No. 386 2014 November 02
by Robin Scagell

SMELLY COMET!
University of Bern

How does a comet smell? Since early August the Rosetta Orbiter Sensor
for Ion and Neutral Analysis (ROSINA) is analyzing the gases of the
comet Churyumov-Gerasimenko with its two mass spectrometers. The
chemistry of the coma of the comet is surprisingly rich already at
more than 400 million kilometres from the Sun. The gases detected
include hydrogen sulphide, ammonia, formaldehyde, hydrogen cyanide,
methyl alcohol, sulphur dioxide and carbon disulphide. Such a mixture
would make a most unattractive (not to say lethal) smell on Earth, but
the density of those molecules in the cometary coma is still very low,
and the main constituents of the coma are water and carbon dioxide
molecules mixed with carbon monoxide. That all makes a scientifically
interesting mixture that may be relevant to studies the origin of the
Solar System, the formation of the Earth and the origin of life. The
idea was that at distances beyond 3 astronomical units the comet would
mostly sublimate the very volatile molecules carbon dioxide and carbon
monoxide, so the fact that ROSINA is already detecting so many more
molecules at large distances from the Sun comes as quite a surprise.
A quantitative analysis will show how the comet compares with other
comets for which data are available (mostly from remote sensing). The
comparison will reveal whether Churyumov-Gerasimenko, being a Kuiper-
Belt comet, differs from the better-known Oort-Cloud comets, and that
may then shed light on some characters of the cloud from which the
Solar System emerged.

[Dreamwoven]

Space.com (www.space.com) has a post on Ceres, wondering whether it can support life. This is the post: http://www.space.com/28068-dwarf-planet-ceres-life-dawn-mission.html?cmpid=558748. Ceres is a dwarf planet, and a probe (Dawn) is heading towards it:

In March 2015, NASA's Dawn spacecraft will arrive in orbit around the dwarf planet Ceres, the largest object in the main asteroid belt between Mars and Jupiter. Ceres is a relatively warm and wet body that deserves to be mentioned in the same breath as the Jovian moon Europa and the Saturn satellite Enceladus, both of which may be capable of supporting life as we know it, some researchers say.

It occurs to me that this interest in whether a planet can support life is about planning a future spacecraft to go there and explore it. If life can be supported there a later probe might be to set up a base there. The nearer such a planet or (dwarf planet) is to earth the better.

There is a long Wikipedia item on Ceres, a dwarf planet (http://en.wikipedia.org/wiki/Ceres_(dwarf_planet)). It is symptomatic of the turmoil in thinking about astronomy that the definition of this object has changed several times in recent history. See the Wikipedia item above which has a section devoted to the classification (http://en.wikipedia.org/wiki/Ceres_(dwarf_planet)#Classification) problematic. Planet, dwarf planet, asteroid, have all been considered by the International Astronomy Union (http://www.iau.org), generally recognised as the world authority in such issues.

[YesNo]

I hadn't thought of labeling comets smelly or not, but it would be an amusing way to describe the gases coming from the comet. What is really interesting is that we can detect and identify those gases.

I also wasn't aware that Ceres might be able to support life. I noticed in the article that Gauss developed a quick method to predict the orbit of Ceres. I wonder what that method was. Also I noticed that if Pluto remained a "planet" then Ceres would have to be relabeled as a planet also.

[Dreamwoven]

We are still in the early stages of exploring the solar system. Pluto https://en.wikipedia.org/wiki/Pluto is the last of the outer planets we have still to visit. All visits so far have been preliminary with the exception of Mars, which has both ground and orbiting probes. Even that is still in its early stages.

Now at last the outermost planet (which as far as we know is Pluto, discovered in 1930, is about to be fleetingly passed by at an accellerated speed New Horizons (https://en.wikipedia.org/wiki/New_Horizons) after launch in 2006. The journey of 9 years is something of an epic in itself, needing several gravity assist (https://en.wikipedia.org/wiki/Gravity_assist) loops around the Moon and Jupiter to build up speed.

Pluto is so far away from the sun that it takes 248 years to orbit the sun. So we only know approximately its orbit and speed.A bit like the early sail circumnavigators the flypass has to be judged accurately so as to come as close as possible without hitting the planet, so reasonable quality data can be collected.

If all goes well "On July 14, 2015, the Pluto system is due to be visited by spacecraft for the first time. The New Horizons probe will perform a flyby during which it will attempt to take detailed measurements and images of Pluto and its moons.[25] Afterwards, the probe may visit several other objects in the Kuiper belt (https://en.wikipedia.org/wiki/Kuiper_belt).[26] (Pluto, Wikipedia)

[Dreamwoven]

Comet Lovejoy is showing well just now: http://earthsky.org/todays-image/watch-for-comet-lovejoy . Europeans check out http://www.eagleseye.me.uk/Sky/Wordpress/?p=3527

[YesNo]

I hope I'll be able to see this. The skies are mostly cloudy here and when the clouds are gone then the urban lights make things difficult to see.

Out of my west window, the one I mainly look out from my home office, I have often seen Venus setting after the Sun.

[Dreamwoven]

I thought this was interesting from the Society for Popular Astronomy.

A CHRISTMAS COMET?
By Jonathan Shanklin, SPA Comet Section Director

There is a chance that Christmas will bring with it a binocular comet
that could even become visible to the unaided eye in the evening sky.
Terry Lovejoy, from Queensland, Australia, discovered comet 2014 Q2 on
August 16 with a CCD camera on his 0.2-m Schmidt-Cassegrain. Initially
of 15th magnitude, the comet has brightened quite rapidly on its way
to perihelion at 1.3 AU at the end of January. Currently visible from
the Southern Hemisphere as a 7th-magnitude object, it is moving
northwards and may become visible low down in the south just before
midnight on Christmas Eve. It continues to move northwards, and by
early January the comet will be visible in the early evening. It
should be at its brightest in mid-January and could remain visible in
binoculars until well into March. It is unlikely to show much of a
tail, but one of a degree or so in length might be seen with
binoculars. Interesting observing opportunities include the early
hours of December 29 when the comet is very close to M79, mid-January
when it is close to the Pleiades, and February 2 when it passes
between M 34 and NGC 752.

[YesNo]

Between January and March, that should give me enough time to spot it. I know where the Pleiades are, so I'll be looking in that direction.

Last night was partially overcast. I could make out a star or two if they were bright enough until the clouds covered them again.

[Dreamwoven]

The day before yesterday was meant to be a good day to see an aurora borealis display, a combination of high sunspot activity and clear skies. British newspapers reported widely on this with pictures. They were seen as far south as Newcastle, with blue and golden lights flashing. Here in Sweden we live at about the latitude of the northernmost Shetland Isles, at 66 degrees North, but saw nothing. Then again we did not go out, as it was -15 celsius that night. Can't stand about in that kind of cold.

[YesNo]

This has been the first clear evening in a long time. Although there is still light pollution where I live, I was able to find my way from Orion to Gemini, Canus Major and Taurus. In trying to find the names of the stars in the Pleiades (http://en.wikipedia.org/wiki/Pleiades) I noticed that there may be something wrong with the Hipparchus distance measurements:


The latest result (August, 2014)[21] used very long baseline radio interferometry (VLBI) to determine a distance of 136.2 ± 1.2 pc, conclusively showing "that the Hipparcos measured distance to the Pleiades cluster is in error." This demonstration of an unrecognized error in the Hipparcos data has implications for the similarly designed Gaia mission.

I thought Hipparchus results were the current best estimate.

[Dreamwoven]

Since Christmas Eve I have not been able to get outdoors to see the clear skies we have at nights. It has been -15 celsius here, and I have major heart problems, so I try to curb my impatience. I can see the Plough (I think its the Sickle in American) out of our one north facing windows. Not seen any of the dramatic aurora borealis yet either.

[Dreamwoven]

Comet Lovejoy looks to be showing well this month. I subscribe to Eagleseye (http://www.eagleseye.me.uk/Sky/Wordpress/?p=3531) (an Englishman's blog ) and just received a post just published which give some info and a picture of the comet.

[YesNo]

Based on that blog, Comet Lovejoy is in Lepus. Although the skies have clouded over, I'll see if I can at least find Lepus tonight.

[Dreamwoven]

The SOCIETY for POPULAR ASTRONOMY

Electronic News Bulletin No. 387 2014 November 23


TAIL DISCOVERED ON ASTEROID HYGIEA
Carnegie Institution

A new active asteroid, numbered 62412, has been discovered in the main
asteroid belt between Mars and Jupiter. It is the first comet-like
object seen in the Hygiea family of asteroids. Active asteroids are a
newly recognised phenomenon and 62412 is only the 13th known active
asteroid in the main asteroid belt. It is estimated that there may
be about 100 of them in the main asteroid belt. Active asteroids
have stable orbits between Mars and Jupiter like other asteroids;
unlike other asteroids, however, they sometimes have the appearance of
comets, when dust or gas is ejected from their surfaces, creating a
sporadic tail effect. Astronomers recently discovered a tail on
62412, an object which had been known as an ordinary asteroid for over
a decade. The reasons for the loss of material and the formation of a
tail in active asteroids are unknown, although there are several
theories such as recent impacts or sublimation from solid to gas of
exposed ices.

In the past, asteroids were thought to be mostly unchanging objects,
but an improved ability to observe them has allowed scientists to
discover tails and comas, the latter being like the thin envelopes of
atmosphere surrounding comets' nuclei. Discoveries such as this one
can help researchers to determine the processes that cause some
asteroids to become active. They found that 62412 has a very fast
rotation that may shift surface material, some of which may leave the
surface and form the comet-like appearance. The tail may be created
directly from material ejected from the fast-rotating body, or from
ice within it subliming into water vapour after being freshly exposed
on the surface. The density of 62412 has been found to be typical of
primitive asteroids and not consistent with the much lower densities
comets.

[YesNo]

I hadn't even considered that asteroids could have tails and that having tails made them "active".

I looked for Comet Lovejoy last night. I could barely make out the top of Lepus, but at least part of it was identifiable. I had to use binoculars to see the stars below Orion and then try to match the patterns with what I saw in the chart. It is warmer for me here, well above freezing. If it got to -15 degrees C I would not be out in it either.

I think I also found Jupiter. It was bright enough, but not quite where I expected it to be, but then nothing else seemed to fit since I could make out the constellations. I was looking for Leo and Cancer.

Viewing constellations along the horizon makes them seem larger than when they get higher. I also noticed the Hyades cluster around Aldabaran in Taurus. There were clearly more visible stars (through binoculars) in this location than around it, but it was not as compact as the Pleiades. Also the Orion Nebula looked like a fuzzy patch of light, suggesting there is more there than just a star.

[Dreamwoven]

Comet Lovejoy looks to be a visible comet this time round. Here is more info on it. I hope o be able to see it this time with binoculars.

A CHRISTMAS COMET?
By Jonathan Shanklin, SPA Comet Section Director

There is a chance that Christmas will bring with it a binocular comet
that could even become visible to the unaided eye in the evening sky.
Terry Lovejoy, from Queensland, Australia, discovered comet 2014 Q2 on
August 16 with a CCD camera on his 0.2-m Schmidt-Cassegrain. Initially
of 15th magnitude, the comet has brightened quite rapidly on its way
to perihelion at 1.3 AU at the end of January. Currently visible from
the Southern Hemisphere as a 7th-magnitude object, it is moving
northwards and may become visible low down in the south just before
midnight on Christmas Eve. It continues to move northwards, and by
early January the comet will be visible in the early evening. It
should be at its brightest in mid-January and could remain visible in
binoculars until well into March. It is unlikely to show much of a
tail, but one of a degree or so in length might be seen with
binoculars. Interesting observing opportunities include the early
hours of December 29 when the comet is very close to M79, mid-January
when it is close to the Pleiades, and February 2 when it passes
between M 34 and NGC 752. There is a finding chart on the SPA web
pages. Making a sketch is a good way to train the eye to see faint
features in astronomical objects, and those of a diffuse comet tail
are often particularly subtle. Spend some time getting fully
dark-adapted, then try looking a little bit away from the comet, but
keeping it in your field of view. That technique of 'averted vision'
sometimes allows you to see faint objects that cannot be seen when
looked at directly. Do send me your observations, which could include
magnitude estimates, drawings, written descriptions or images.

[YesNo]

I was able to get more bearings and I think that was Jupiter I saw. I saw it in the morning as well. It looks like it will be setting around the time the sun rises.

Edit - I saw a halo around the moon tonight. I understand they are like rainbows but coming from higher clouds.

[Dreamwoven]

Yesterday I learned of a space craft launched by NASA in 2006 called Dawn. It continues the exploration of the solar system by visiting two denizens of the Asteroid belt (https://en.wikipedia.org/wiki/Asteroid_belt) between Mars and Jupiter. Ceres, a dwarf planet (https://en.wikipedia.org/wiki/Ceres_(dwarf_planet)) about 1,000 kilometres in diameter. This is a considerable size for an asteroid, not much smaller than Pluto, which has a diameter of 1,400 km (note the confusion surrounding terminology: are they dwarf planets, planets or asteroids?). The second object is the asteroid Vesta with a diameter of 500 km. There is a very extensive NASA website (http://dawn.jpl.nasa.gov) on these two. The Dawn craft uses an ion propulsion system and includes Dawn Blog (http://dawnblog.jpl.nasa.gov) that was started in 2006, and initial photographs of Ceres.

I leave those who are interested to explore the website further.

[YesNo]

I found Saturn this morning thanks to Google Sky Map. I pounted the phone in the direction of a star and the map showed it to be Satirn. I could even follow the ecliptic all the way around the earth by pointing the phone. It seemed odd to point the phone toward my feet and see a star map. I guess it hasnt sunk in that the earth is round.

[YesNo]

The moon and Jupiter were in conjunction as they rose last night. It was impressive.

[Dreamwoven]

Yes, I saw Jupiter, too. It looked impressive, I don't think I've ever seen it so bright. There isa a good chance to see it tonight and if so will use my binoculars to see it.

I looked up google sky map as well, its only for use with modern mobile phones which we don't have.

[YesNo]

Before the clouds came in last night, I saw Venus and Mercury almost line up. I've noticed these two before and even saw the phases of Venus when in Wisconsin through binoculars where it is darker a few years ago.

Yes, you would need a tablet or phone to run that app. It is not really necessary to have it, however, if you know where things are.

[Dreamwoven]

We have had a lot of snow lately and its now too cold to go out, but I enjoyed seeing Jupiter near the full moon, very bright it was.

EarthSky website has an article about travel beyond the solar system, different kind of engines, and what would be needed to get to the nearest galaxy, Alpha Centauri (http://earthsky.org/space/alpha-centauri-travel-time?utm_source=EarthSky+News&utm_campaign=a6578c2d68-EarthSky_News&utm_medium=email&utm_term=0_c643945d79-a6578c2d68-394044013#conventional), some 3.4 light years away There is also a piece on rare ice halo displays, what fantastic patterns!

Apps are for me very strange, I would never know how to set it. Press a button I guess. But you are right, its easy to find any post without it.

[Dreamwoven]

Astronomy Now has an article on the probe Huygens that was sent down to Saturn's largest moon, Titan (https://en.wikipedia.org/wiki/Titan_(moon)), dropped in 2005 to land on Titan. Huygens was a special mission to study an alien moon, and detached from Cassini, which carried on to map the middle planets of the solar system, especially Jupiter and its moons and Saturn and its moons. Slowly but surely this preliminary survey and others like it are building up a picture of what our solar system consists of, the planets and moons and what they look like in general terms, the major orbiting asteroids, the dwarf planets, and landings done on the most interesting of these. So far Mars is the only planet to be examined more closely. No doubt after this preliminary mapping more detailed probes like the ones sent to Mars will be sent to do a careful analysis of at least some of our fellow-denizens of this minor solar system that is our home.

[YesNo]

The article on Titan was interesting. It dawned on me, finally, what tidal locking means. Also the attempt to warp space-time to make travel to Alpha Centauri did not previously seem to be to be something that was possible. Maybe it isn't.

I realize I don't much about astronomy, probably less that an astrologer knows. I can't even name the 12 constellations in the zodiac correctly in order, but I am beginning to identify them.

[Dreamwoven]

I had no idea the Huygens probe (https://en.wikipedia.org/wiki/Huygens_(spacecraft)) had been dropped on Titan and had done its work. Ten years ago I was not interested in astronomy.

This may well be the pattern to do an initial exploration of al the moons in the solar system. There must be around 100 of them altogether. But it does show how little we know of our own solar system.

There is another interesting article in EarthSky on the possibility, according to new calculations, of there being two more planets (http://earthsky.org/space/two-or-more-planets-beyond-pluto?utm_source=EarthSky+News&utm_campaign=4cdea82cc8-EarthSky_News&utm_medium=email&utm_term=0_c643945d79-4cdea82cc8-394044013) undiscovered beyond Pluto. As Pluto takes over 200 years to complete one orbit round the sun, any others might take much longer. Mind-boggling.

[YesNo]

I wasn't aware of the possibly of there being extreme trans-Neptunian planets. I tend to assume that we have better knowledge than we actually do.

I was reading the recent Scientific American in the library yesterday and found that scientists looking for exoplanets are more interested in planets that are super-habitable, using the quantity of biomass that a planet can support to define better habitability. Such planets would be larger that ours with a sun that is smaller. The planet would be also better situated in the habitable zone around the sun than the Earth currently is. The larger gravity would reduce the heights of mountains and depths of the oceans. The sun would live longer. In our case, the increased heat of the Sun would bring us to the inner range of the habitable zone in half a billion years making earth a dead planet 1.75 billion years from now even though the Sun will continue for 4 to 5 billion years.

I was thinking that I do like high mountains, so maybe our planet is not so bad even though the quantity of biomass could be increased with a different environment.

[Dreamwoven]

Space.com has an interesting detailed post on the planets beyond Pluto (http://www.space.com/28284-planet-x-worlds-beyond-pluto.html?cmpid=558943).

What you write about the Scientific American article is very interesting. It is clear, I think, that this is uppermost in the mind of the major space researchers like NASA. The Saturn moon that the Huygens probe (https://en.wikipedia.org/wiki/Huygens_(spacecraft)) landed on was chosen because of its large seas (see Lakes of Titan (https://en.wikipedia.org/wiki/Lakes_of_Titan)). There is a long separate post on this and with many footnotes. They turn out to be liquid ethane, methane and propane. What they are looking for are large bodies of water or ice that can provide a plentiful supply of potable water with minimal (or even better with no) chemical alteration. There is a separate Wiki page on the project called Titan Mare Explorer (https://en.wikipedia.org/wiki/Titan_Mare_Explorer), which NASA have applied for funding. Hoping to launch in 2016. No doubt that is also why Mars is of interest as its has ice caps like Earth does.

[YesNo]

The idea of landing a probe in a sea breaks through my mental box of what is possible. I usually assume probes have to land on solid ground.

The skies have been overcast, but I found a book: Dinah Moche, "Astronomy A Self-Teaching Guide", that I have started reading. I also downloaded a planetarium app from Celestron that is used to guide their telescopes. If I can't see the stars outside, I can always look at that.

[Dreamwoven]

I seem to remember that US astronauts landed in the Pacific?

I guess that's what gives smart phones the edge, a range of apps that extend their usefulness. And for astronomy, in the dark your screen is lit up. Funnily enough I have been considering getting a sky chart to guide me through the constellations, but I have not done it yet. I saw Mars when the moon was waning (its easier to see then as the moon can be dazzling when its full.)

Dinah Moche, Astronomy A Self-Teaching Guide looks like a useful book. I might buy it for myself.

[NikolaiI]

I will definitely have to get back into it soon. . I've been focusing on other things but I will get back into studying it pretty soon.

One thing I found interesting was the maria, or seas on the moon. . I chose my "Lake of Dreams" location a few years ago from the list of them. . now I'm thinking it would be nice to memorize them. The most famous ones might be the Sea of Tranquility or the Sea of Serenity; Mare Tranquillitatis and Mare Serenitatis respectively. When I did a quick search on Lake of Dreams, I found it's interestingly also a 3-acre lake in Vegas, surrounded by a forest, and also a 77-acre campground in Michigan. Random, non-astronomy related fact. Unless you're viewing from another planet, then it would be astronomy. :p

Maria on the Moon (http://en.wikipedia.org/wiki/List_of_maria_on_the_Moon)

[NikolaiI]

But I can redeem myself because I just found a doubly-related fact about astronomy. One of the maria is called Mare Humboldtianum, named after explorer and naturalist Alexander von Humboldt. . .

also known as "Q" from Star Trek.

http://upload.wikimedia.org/wikipedia/commons/thumb/3/36/Stieler%2C_Joseph_Karl_-_Alexander_von_Humboldt_-_1843.jpg/300px-Stieler%2C_Joseph_Karl_-_Alexander_von_Humboldt_-_1843.jpg

At least, in that portrait.

[YesNo]

Yes, landing in water on earth is probably the easier way to land. I didn't realize there was anything liquid on those other planets to land on.

Regarding the names of the mare, or maria, or whatever they are called, on the moon, I don't even know where all the great lakes are on earth except for the one I live near.

[Dreamwoven]

But I can redeem myself because I just found a doubly-related fact about astronomy. One of the maria is called Mare Humboldtianum, named after explorer and naturalist Alexander von Humboldt. . .

also known as "Q" from Star Trek.

http://upload.wikimedia.org/wikipedia/commons/thumb/3/36/Stieler%2C_Joseph_Karl_-_Alexander_von_Humboldt_-_1843.jpg/300px-Stieler%2C_Joseph_Karl_-_Alexander_von_Humboldt_-_1843.jpg

At least, in that portrait.

I've never read Kosmos, perhaps I aught to give it a go.

YesNo, I think Titan is one of the few planets that does have liquid lakes on the surface. They are quite big, too, not like to ponds or even the lakes in the Lake District. More like Lake Michigan, even bigger: Lakes of Titan (https://en.wikipedia.org/wiki/Lakes_of_Titan).

[Dreamwoven]

Saturn's largest moon Titan is the only "planetary-like" object in our solar system that we know has surface seas. Not that they are very tempting to swim in let alone drink - methane seas means it is likely to be somewhat oily. The February 2015 issue Astronomy Now has a long article on this planet from which I quote a small part:

"Yet there is more to Titan than just lakes, which make up around ten percent of the surface. There are also dunes of ice crystals blown by the gentle winds that Huygens (http://en.wikipedia.org/wiki/Huygens_(spacecraft)) detected on the way down, as well as the presence of cryo-volcanoes (http://en.wikipedia.org/wiki/Cryovolcano). A balloon mission in contrast to TIME (an application for funding a floating probe that was not selected by NASA) would be able to circumnavigate the Titan from the air and take in all the different types of scenery, hovering over areas of interest, dropping down to take samples and perhaps even deploying landers or mini-rovers

Titan is actually quite good for this sort of thing, with its thick atmosphere and low gravity. A balloon could do a complete circuit of Titan in about two weeks.".

The article goes on to say that both TIME and this project remain "stuck in developmental hell". I guess that means they are having to rework and resubmit their proposals.

[YesNo]

The idea of a "cryo-volcano" bursts another conceptual box for me. On a very cold planet one can get action from the "volatile" elements that have volcano like effects. Here is another article on the difference between a "gas" and an "ice" planet: http://en.wikipedia.org/wiki/Volatiles

Last night was clear and Jupiter was very bright being on the same side of the sun as the earth. I probably will not be able to see the retrograde motion of Jupiter (movement toward the west through the sky relative to the stars, if I got that right) since it is hard to make out the stars around it because of the light pollution, but I'll see if I can follow it's path. When the planet is in opposition is when one should be able to see this.

[Dreamwoven]

A huge planet with many rings has been identified in another galaxy. This BBC item explains how it might look in our own skies: http://www.bbc.com/news/science-environment-31001936

[NikolaiI]

Has anyone heard of the Aragoscope? My friend posted a link to it on Facebook, http://www.gizmag.com/aragoscope-lensless-telescope/35761/ the author of the article says it could produce images much sharper than the Hubble.

[YesNo]

The Aragosphere sounds interesting being a large diffraction lens. I don't really know what one of these are, but it looks like are like 3d glasses which made it all the more confusing. Anyway it would be nice to get one of these telescopes working.

It is also amazing that astronomers can find such things as a ring planet as it passes over a star. How do they know that is what they are looking at?

I saw a news item about the recent asteroid that passed near Earth. It has a tiny moon circling it. http://www.cnn.com/2015/01/26/us/asteroid-flyby/

So far the skies have been too cloudy to see Jupiter. I would like to watch Jupiter appear to move westward through the sky by comparing it to stars in the background. Normally planets should go eastward. On February 6th, Jupiter should be in opposition to the Sun.

[YesNo]

There was a nice snow fall last night so finally the clouds are producing something interesting to look at. I finished the first chapter of Moche's "Astronomy" and I continue in my realization of little I knew about the sky since I started paying attention to it because of this thread.

It occurred to me two nights ago, that it makes sense that ancient people would be able to identify the planets. They are so bright. They are the first things after the Moon that stand out and then they move about unlike the stars which seem relatively stable in their rotations around the Earth. And they sort of follow the Sun's path. I didn't realize how obvious all of this was.

[NikolaiI]

That second paragraph really, really made me smile for some reason, YesNo. I'm still in the very beginning stages of the astronomy knowledge quest. But that's a good place to be, I wot. I am very much planning on getting back into it very soon - I have been meaning to, but I have just been into poetry and chess so much - but okay, I am going to tomorrow.

[Dreamwoven]

The Aragosphere sounds interesting being a large diffraction lens. I don't really know what one of these are, but it looks like are like 3d glasses which made it all the more confusing. Anyway it would be nice to get one of these telescopes working.

It is also amazing that astronomers can find such things as a ring planet as it passes over a star. How do they know that is what they are looking at?

I saw a news item about the recent asteroid that passed near Earth. It has a tiny moon circling it. http://www.cnn.com/2015/01/26/us/asteroid-flyby/

So far the skies have been too cloudy to see Jupiter. I would like to watch Jupiter appear to move westward through the sky by comparing it to stars in the background. Normally planets should go eastward. On February 6th, Jupiter should be in opposition to the Sun.

Germany is building a telescope to launch in 4 years time that will be available for public use. You can read about it in Popular Astronomy January-February 2015 pp. 19-20. Great to get kids interested in space, no doubt many schools will be using them, 24 hours a day, no problem with clouds. I expect there will be a long waiting list for individuals to use it, though.

Yes, it looks cute, there are other asteroids that have moons.

They measure the size by time lapse of its shadow passing over the sun. It is a big planet with an even vaster ring-system
We are getting more images of Pluto and its moon Charon as New Horizons hurtles closer to Pluto.

[YesNo]

I finished the second chapter of the Astronomy book I was reading. It was about the various telescopes and how they examine electromagnetic waves of different frequencies to get information. It occurred to me that our whole visibility on the universe, even to parts that are not visible to our eyes, is due to electromagnetic waves.

I sort of knew that but didn't realize it. Gravity and quantum fields are added in with the assumption that what works down here works up there as well.

[Dreamwoven]

Interesting. Perhaps a related issue is the infinity of the universe from the Big Bang. There is a fascinating discussion here: http://earthsky.org/space/what-if-the-universe-had-no-beginning?utm_source=EarthSky+News&utm_campaign=4361fc475b-EarthSky_News&utm_medium=email&utm_term=0_c643945d79-4361fc475b-394044013. The discussion by readers following is also interesting.

[YesNo]

The comments were entertaining. And they go on and on.

On the 9th, I was able to see Jupiter. I understand it was in opposition on that day. It was very bright, as I suspect it should be since it is nearer to the Earth at that point. I wasn't able to notice that it moved westward. I couldn't get reference stars in the background to compare its position to.

[Dreamwoven]

I've seen Jupiter several times lately, it is quite distinct being very bright. It is in the east and a smaller planet is below it, probably Mars. I can't wait for the snow to go and spring to come to see it better with my binoculars.

[YesNo]

Last night was one of the best nights to look at the sky. It was clear but cold. I wasn't motivated to get out the binoculars, but tonight, if it stays that way I'll look for that comet. It is probably past Lepus. It occurred to me if I wanted to see Jupiter reverse directions I could use the app on my phone, however, that is sort of cheating.

[Dreamwoven]

Don't know anything about mobile phones, but I just read this article in EarthSky (http://earthsky.org/space/how-big-is-the-biggest-monster-star?utm_source=EarthSky+News&utm_campaign=658e6e8a01-EarthSky_News&utm_medium=email&utm_term=0_c643945d79-658e6e8a01-394044013). I can't imagine suns that big, mind-boggling. And no-one knows how they are possible. They don't seem to fit the life-cycle of suns that we know of.

[YesNo]

It looks like the existence of those large stars falsifies some of the current views of how stars are formed. They are rather close to us. If they are likely to result in a supernova, we might be engulfed in it. But I am not sure. Just how far do the destructive effects of a supernova extend? Unlike an asteroid, we wouldn't know it was coming.

I could see Venus clearly in the west and Mars became visible with the binoculars above it. Jupiter was very bright in the east although I was not able to make out its moons with the binoculars. Perhaps I could see them in a darker area. I remember once seeing the phases Venus goes through with binoculars in northern Wisconsin. It was very dark there.

Also, I found a book by John W. McAnally, "Jupiter and How to Observe It". He mentioned the Association of Lunar and Planetary Observers: http://alpo-astronomy.org/ If I ever build that telescope this spring-summer, I'll probably join this organization. They keep recordings of amateur obsevations along with a form and style for making records. At the moment with my binoculars, I don't see the cloud segments on Jupiter anyway.

[YesNo]

I found out that the supernova would have to be within 100 light years of the earth to be a threat: http://en.wikipedia.org/wiki/Near-Earth_supernova

These stars are further out than that.

[Dreamwoven]

I have no idea how far a supernova of such a massive star extends. But planets near supernova would be turned to cinder. When our sun is ready for that we are done for. But that is just the life-cycle of all stars. I think we have many hundred thousand or even billions of years before our sun goes, at least according to what astronomers today know.

That is an interesting website you found! I've added it to my astro bookmark to look closer at it later.

I say Jupiter again but trying to stand outside and watching with my binoculars I couldn't make out anything like the planet's moons. Have to wait until spring, I guess.

[free]

I looked through a telescope only once. I saw Saturn with its ring. It was a beautiful feeling.

[YesNo]

All I have are binoculars and Google's sky map app on my phone to help me identify what is up there. I am normally not in a dark enough area to see what most people from the past would have easily recognized. The planets (Venus and Jupiter) are very clear. Orion, Sirius, the two main stars in Gemini, the Pleiades and Aldebaran are also amazingly bright. But I can't even see the big dipper clearly.

We wouldn't be here without those supernovas creating the elements that make up the earth. There is a conjecture that an ancient supernova might have caused one of the extinction periods, but it didn't remove all life. Although the sun has some billions of years to go, the earth will probably no longer be in the habitable zone of the sun much sooner.

[YesNo]

I was just looking at Jupiter close to its high point in the sky and I think I can see three of the four Galilean moons with my 7X50 binoculars. Galileo had a 26mm refractor telescope 500 years ago to see these: http://www.atnf.csiro.au/outreach/education/senior/astrophysics/galileo.html

[Dreamwoven]

Thats very encouraging, I look forward to using my 7x50 binoculars in the spring. Too cold still.

Our sun will long outlive the earth and then will destroy it. http://www.space.com/28553-don-t-panic-but-the-sun-will-far-outlive-earth.html?cmpid=559072.

[YesNo]

It looks like we will be able to move to Mars once Earth becomes uninhabitable when the Sun becomes too bright.

I am going to try to reproduce all of Galileo's experiments with the binoculars. Some of them are pretty easy to do like observe the craters on the moon.

After reading McAnally's book on Jupiter, I think I see why I wasn't able to see the moons previously. It was not that the "transparency" wasn't acceptable but that the "seeing" wasn't good. The seeing affects how the Earth's atmosphere distorts what one is trying to look at. A way to improve it is to observe later in the evening. When I saw the moons it was nearly midnight. I should also let the binoculars cool down so they are close to outside temperature before trying to use them. That might be a challenge since it has been rather cold here as well. Also I should not stand on the sidewalk or be near a building early in the evening that is cooling down from the warmer day.

[Dreamwoven]

From a Popular Astronomy email update:
METEORITE MAY REPRESENT BULK OF MARS' CRUST

Brown University

NWA 7034, a meteorite found a few years ago in the Moroccan desert, is like no other rock ever found on Earth. It has been shown to be a 4.4-billion-year-old piece of the crust of Mars and, according to a new analysis, rocks just like it may cover vast swaths of Mars. In a new paper, scientists report that spectroscopic measurements of the meteorite are a spot-on match with measurements from orbit of the Martian dark plains, areas where the planet's coating of red dust is thin and the rocks beneath are exposed. The findings suggest that the meteorite is representative of the 'bulk background' of rocks on the Martian surface. When scientists started analyzing the meteorite in 2011, they knew that they had something special. Its chemical make-up confirmed that it came from Mars, but it was unlike any other Martian meteorite. Previously, all the Martian rocks found on Earth were classified as SNC meteorites (shergottites, nakhlites, or chassignites). They are mainly igneous rocks made of cooled volcanic material, but the new object is a breccia, a mash-up of different rock types welded together in a basaltic matrix. It contains sedimentary components that match the chemical make-up of rocks analyzed by the Mars rovers. Scientists concluded that it is a piece of Martian crust -- the first such sample to be found on the Earth.

[YesNo]

I realize I didn't know what a breccia was, but now it makes sense. I don't see why this particular type of black beauty does not occur on Earth.

Since it is Chinese New Year, I thought I'd try to figure out what that meant. It seems that it is first based on the winter solstice, a solar phenomenon. The second new moon after that is Chinese New Year with the celebration lasting three days.

In the process of looking that up, I found http://live.slooh.com/ which supposedly offers astronomical events for view. I'll try to make it for the new crescent moon event tomorrow.

[Dreamwoven]

Europa, one of the moons of Jupiter (the one with surface seas) may be explored for signs of life: http://www.space.com/28614-nasa-europa-mission-alien-life.html?cmpid=559074.

The Europa Clipper (http://solarsystem.nasa.gov/missions/profile.cfm?MCode=EuropaClipper) is one of the projects under consideration, a probe that sails around Euro in its atmosphere taking measurements.

[mal4mac]

Interesting observation about there being no threads (but this one) on astronomy. Is mainstream literature anti-astronomy? Here's some quotes to back up my thesis:

Tennyson:

"Storm, and what dreams, ye holy Gods, what dreams!
For thrice I waken'd after dreams. Perchance
We do but recollect the dreams that come
Just ere the waking. Terrible: for it seem'd
A void was made in Nature, all her bonds
Crack'd; and I saw the flaring atom-streams
And torrents of her myriad universe,
Ruining along the illimitable inane,
Fly on to clash together again, and make
Another and another frame of things
For ever. "

Whitman:

WHEN I heard the learn’d astronomer;
When the proofs, the figures, were ranged in columns before me;
When I was shown the charts and the diagrams, to add, divide, and measure them;
When I, sitting, heard the astronomer, where he lectured with much applause in the lecture-room,
How soon, unaccountable, I became tired and sick; 5
Till rising and gliding out, I wander’d off by myself,
In the mystical moist night-air, and from time to time,
Look’d up in perfect silence at the stars.

William Blake was critical of reductive scientific thought. In his famous picture "Newton", the straight lines and sharp angles of Newton’s profile suggest that he cannot see beyond the rules of his compass.

http://www.tate.org.uk/art/artworks/blake-newton-n05058

Behind him, the colourful, textured rock may be seen to represent the creative world, to which he is blind.

[mal4mac]

I looked through a telescope only once. I saw Saturn with its ring. It was a beautiful feeling.

I was obsessed with astronomy, for a period, as a kid, and young adult. Seeing Saturn's rings was certainly a highlight, along with seeing Jupiter's moons and some of the Messier objects. This seems like a Whitmanesque response, "In the mystical moist night-air ... Look’d up in perfect silence at the stars." But I found, on getting heavily into it, it becamet rather tedious, "When the proofs, the figures, were ranged in columns before me; When I was shown the charts and the diagrams, to add, divide, and measure them;..., I became tired and sick".

Whitman makes astronomy, here, sound like filling in tax return. Astronomy is strange! Part poetry and part accountancy.

Note Tennyson's "illimitable inane". He has a point - I mean what's up there really? Not Gods or even humans, just a bunch of inane rocks. But then again, these rocks are playing in a vastness beyond comprehension, within endless time; which leads to incomprehension, awe, and terror. Maybe issues too big and difficult for literature to comprehend and cope with? On one side, the most extreme inanity, on the other, the highest sublimity. Strange subject!

[Dreamwoven]

I agree with you, it is a strange subject, very technical yet very dramatic. Of course, this website is about literature so I couldn't expect a lot of interest in astronomy. Thats why this is only one thread out of hundreds or even thousands of threads.

I too saw the moons of Jupiter through a friend's telescope and only became interested in astronomy today where the internet covers it pretty well. Your quoting of Tennyson and Whitman shows that poetry is written inspired by the night sky.

YesNo, thanks for yet another link! Ive added it to my astro bookmark. There are now several people dropping by with posts: Gilliat Gurgle, NikolaiI, 108 Fountains, Calidore, so it is a topic of wide interest.

We are also now in a fascinating era for space exploration.

[YesNo]

That there might be life under the ice of Europa sounds intriguing. It is so far from the sun.

I tried to see the moons of Jupiter with my binoculars two nights ago and was not able to. Another part of the problem may be with the way I am focusing the binoculars. One part surely is that I am not using a tripod.

Regarding literature, science fiction has some interest in astronomy. What I have discovered is that prior to this thread I didn't realize that I didn't know anything about astronomy or even astrology. It is only recently that I understood what Jupiter's retrograde motion even meant. Then looking at the sky, even I can see Jupiter with all the light pollution getting in the way. I can see why this planet stood out in the past.

[Dreamwoven]

As you say, Jupiter is very easily seen now, but by the time it get warm enough for me to go out and look with my binoculars it may be too light for viewing.

I've started to visit the New Horizons (http://pluto.jhuapl.edu/index.php) website almost daily. It is still 1 Au to Pluto (that's about the distance of Earth to the Sun) but the probe is flying extremely fast. There are now images of two of the small moons of Pluto, Nix and Hydra (https://en.wikipedia.org/wiki/Moons_of_Pluto). There were found by Hubble space telescope recently.

[free]

I follow this thread with great interest, but, unfortunately, I have not enough knowledge about astronomy to post any comment. Maybe it would be interesting to remind that Newton's laws of motion written in 'Principia', in 17th century, are basical for today's cosmic exploration.

[YesNo]

I forgot about New Horizons. It looks like Pluto has at least five moon and Charon is tidally locked with Pluto meaning both Charon and Pluto show each other the same side like the moon shows us its same side.

If you have a smart phone, free, you can download one of the sky apps. They are just maps, but one can watch the relative positions of the planets change through them and then know where to look when the sky is transparent enough to view them. Although I am interested in the current discoveries, I am even more interested in how we got to where we are in our understanding and the different views people had in the past including astrological views. We should be able to use Newton's laws and astronomical data that he would have had available to be able to predict where a planet will be. I still don't know how to connect those dots.

[Dreamwoven]

I don't have a smart phone.

I discovered a new kind of cloud: lenticular clouds, they look odd and spaceship like. You can read about it on EarthSky (http://earthsky.org/earth/best-photos-beautiful-lenticular-clouds-around-the-world?utm_source=EarthSky+News&utm_campaign=33dd22efa1-EarthSky_News&utm_medium=email&utm_term=0_c643945d79-33dd22efa1-394044013). One of the comments is by a pilot and he said in a comment that they can be dangerous to fly into, because they cause a lot of turbulence. The last picture is particularly dramatic catching the red setting (or rising?) sun!

Clouds could be a subject of its own to view and take pictures of, the way sunlight catches them, etc. Tornadoes and even minor whirlwinds are also interesting.

[YesNo]

I know you don't have a smart phone. I'm still trying to figure out how to use mine although I've had it long enough. Because the map changes daily I am able to see Jupiter move to the west (retrograde). One of the things I noticed using it is that the sun is still in Aquarius but astrologically we are supposed to be in Pisces. I realize this is due to the Precession of the Equinoxes, but I didn't really understand (and probably still don't) what that meant until just recently. With so much stuff spinning around it is hard to know which direction is prograde and which is retrograde or "precessing". I expect the sky to move from east to west because my limited experience only sees the diurnal motion, but planets move from west to east across the sky.

One of the things I am trying to make sense out of, which I know is not of great astronomical importance, are these lyrics by James Rado and Jerome Ragni from the Hair musical: http://en.wikipedia.org/wiki/Aquarius/Let_the_Sunshine_In


When the moon is in the Seventh House
And Jupiter aligns with Mars

I understand the alignment part. The planets are in conjunction. But what is this moon being in the seventh house?

The lenticular clouds do look like ufos although what they remind me of are the clouds on Jupiter that seem to flow in lines across the planet. I don't know how clouds can do something like that on Jupiter nor how clouds can move like those lenticular examples on earth.

[YesNo]

I think I'm beginning to understand what a "house" is. Correct me if I'm wrong.

The precession of the equinoxes has been known for over 2000 years. http://en.wikipedia.org/wiki/Axial_precession What it means is that when the equinox occurs the sun will actually be in a slightly different position with respect to the stars than it was last year. It looks as if the stars are moving westward (retrograde, precession) with respect to the vernal equinox. If one goes beyond the obvious diurnal motion, one expects the stars to move eastward.

Around 500 BC, the sun was in Aries. Today it will be on the beginning edge of Aquarius. So that is why people talk about the "age of Aquarius" because at the time of the equinox the sun will be this year around Aquarius however one defines its boundaries, but not Aries any more. Each year beginning with the vernal equinox is divided into twelve units of 30 degrees each. These are the "houses" and they correspond to constellations starting with Aries and ending with Pisces. However, these are not the constellations that the sun is actually going through at the time, but just a name for a different division of the sky referencing back to the order of these constellations in the zodiac.

What I wonder is how did Hipparchus discover this? What tools did he use to see that there was a difference at the vernal equinox?

[mal4mac]

What I wonder is how did Hipparchus discover this? What tools did he use to see that there was a difference at the vernal equinox?

Read on:

http://en.wikipedia.org/wiki/Axial_precession#Hipparchus

"According to Ptolemy's Almagest, Hipparchus measured the longitude of Spica and other bright stars. Comparing his measurements with data from his predecessors, Timocharis (320–260 BC) and Aristillus (~280 BC), he concluded that Spica had moved 2° relative to the autumnal equinox."

For tools check out:

http://en.wikipedia.org/wiki/Astrolabe#Ancient_world

http://en.wikipedia.org/wiki/Dioptra

Precession is an interesting phenomenon, another example is the precession of the perihelion of Mercury. The measurements of this were found to disagree with the predictions of Newtonian theory. Einstein's general theory of relativity explained them, and this was perhaps the first significant proof of this theory.

[YesNo]

Yes, I missed the comparison between Hipparchus' measurements and those over 100 years prior to his measurements. I may try making an astrolabe out of paper: http://www.joh.cam.ac.uk/library/library_exhibitions/schoolresources/astrolabe/build

I looked at the moon through my binoculars thinking of what Galileo's arguments might have been. Everyone knew the moon was not a uniform color, but they didn't think there were mountains on the moon which Galileo tried to show by pointing to the shadows. If I step back and pretend that I don't know there are craters on the moon and just looked would I actually see the evidence for a non-uniform surface?

[Dreamwoven]

I've always understood "Houses" to refer to astrology rather than astronomy. Having said that, the ancients especially in India and China, were working with houses at the time when the distinction between astronomy and astrology was not made. Not sure about that, though...

[YesNo]

I'm trying to figure out how the Indian astrology differs. I think they used the the stars more than the Sun during the Spring equinox as a starting point. The "house" is just a 30 degree region of the sky from a starting point. There are also "decans" or 10 degree regions of the sky putting three of these in each house.

With Galileo, I understood he found it difficult even getting those on his side to see what he saw through his telescope and I am beginning to see the difficulty by looking through the binoculars. I think I can see the evidence for the non-uniform lunar surface and the Milky Way being composed of stars, but I am having a hard time seeing the moons of Jupiter. One would have to see them clearly enough to notice that they change position around Jupiter.

It also seems obvious that Venus and Mercury should be circling the Sun because they switch from morning to evening stars and do not stray too far from the Sun. This was clear to Martianus Capella in the fifth century, but went against Ptolemy's authority: http://en.wikipedia.org/wiki/Martianus_Capella

[Dreamwoven]

I know very little about astrology, I'm afraid. Once I tried to cast a horoscope, but I didn't trust my judgements!

The first big event is very soon, when the Dawn mission (http://dawn.jpl.nasa.gov) approaches the dwarf planet of Ceres on 6th March.

I was amused by the fact that there is a rather vicious debate over Pluto's status and a clique of pluto-haters (http://www.space.com/28656-its-time-to-restore-plutos-good-name.html?cmpid=559075). Funny how even in astronomy you still get the most emotional debates.

[YesNo]

It looks like we will learn more about Ceres and Pluto this year. That they have not cleared their environments seems to be the major reason they are not considered "planets". Those bright spots on Ceres have caught my interest.

I found Nick Lomb's "Transit of Venus" in the library. There are rare events when Venus crosses in front of the sun. They would be evidence that Venus is circling the Sun along with the phases of the planet. The first time this was seen was in 1631 and I guess the prediction of when it occurred is due to Kepler. Prior to sending radio signals to get the distance from Earth to Venus, the transit was supposed to be a way to determine what that distance was and then using Kepler's laws determine the distance form the Earth to the Sun to use as a basis for measuring other distances.

[Dreamwoven]

The definition of the IAU (https://en.wikipedia.org/wiki/International_Astronomical_Union) is odd. Too detailed and with too many ifs and buts. Has Earth cleared its orbit? Depends how you define it. See this post (http://io9.com/5775229/should-earth-get-demoted-from-planet-status-just-like-pluto) on a new astro website I found yesterday.

[YesNo]

If Earth completely cleared its neighborhood there wouldn't be any fear of an asteroid hitting earth. I didn't know there were five dwarf planets: Ceres, Eris, Pluto, Makemake, and Haumea. I hadn't even heard of the other three. Why isn't Pluto's largest moon Charon included in the list of dwarf planets? They are tidally bound and similar in size that they could be said to be orbiting each other as they orbit the sun. The idea of a lost planet or two way out there that we haven't found is also interesting.

[Dreamwoven]

I believe Pluto's large moon is classed as well a moon. Your comment highlights the ludicrous nature of the definition of a planet. Pluto-Charon is a new phenomena as far as I know. We have seen it before in suns that are locked together in other galaxies, and sometimes planets going round one of the double stars is thrown over to going round the other. I saw a post on this in Astronomy Now a year or two ago. If that is not having an "uncleared orbit" I don't know what is! IAS is still very bound to a solar-centric view of the universe. There may even be more dwarf planets in orbit around Pluto.

I also agree that the possibility of a large planet going around the sun is intriguing. Pluto takes 3-and-a-half centuries to make one circuit the sun. How long would an even more remote planet/dwarf planet take?

We should know what those whit spots are on Ceres are within the next few days when Dawn goes into orbit around Ceres.

The Dawn Probe has ion propulsion (http://nmp.jpl.nasa.gov/ds1/tech/ionpropfaq.html), so it can use it as a brake to slow it down such that it can be gently captured into Ceres orbit. Then it will stay in orbit for a period to examine Ceres more closely.

[YesNo]

That electric, ion propulsion is interesting. From the link you provided it can make a space craft go ten times faster than chemical propulsion using energy from the sun. I wonder why xenon is used and not some other element? Also I wonder if there is a way to harvest elements in space or around atmospheres of planets to replenish the xenon?

[mal4mac]

Xenon is an inert gas, like Helium and Neon, but heavier. Maybe it's used because it will not react with any of the materials in the spaceship, (e.g., it will not explode like hydrogen and oxygen!) Because it's heavier you can store a greater mass in your fuel container. Anyway, I'm jut guessing - get googling or ask on physics forum.

[YesNo]

I did find that the fuel has to be easy to ionize and have a high mass/ionization ratio (that doesn't make sense to me) along with the contamination issue. Any material could be used as a propellant.

http://en.wikipedia.org/wiki/Ion_thruster#Propellants

[free]

I plan to observe Leo constellation. It is most visible from the late March, through April and May. This constellation seems interesting to me. :)

[mal4mac]

Back in the 1980s, at least, liquid metals were being considered as sources of ions for thrusters. I'm not sure what the situation is today. You would get gallium, or some other metal, to flow along a tungsten needle and generate ions coming off at the point using an electromagnetic field that would then keep the metal-gas ions in line and get them moving at speed. One would think it would be easier to mine metals than extract Xenon from (say) Jupiter's atmosphere, and they would (surely) be easier to store. Check out "liquid metal ion sources" of you want to read up on this.

[YesNo]

Based on the Google Sky Map, both the moon and Jupiter are near Leo. I have only identified Algieba and Regulus in Leo while watching Jupiter. I should be able to see Denebola if the sky is clear enough.

Xenon is supposedly hard to get, but it is apparently easy to ionize. From the article argon is more common. I like the idea of getting energy from the sun and atoms from the atmosphere of the planets one visits for these space probes.

[free]

Last night I saw Orion constellation. It is easily recognized by its three bright stars close to each other called 'Orion's belt'.

[Dreamwoven]

I don't really know either how ion propulsion works, so join the club…
:)
Dawn is getting really close to Ceres, now some 35,000 miles, and retro- ion propulsion is slowing down a bit more. It should enter orbit around Ceres in a couple of days (March 6). I understand that it will be orbiting Ceres but starting on its dark side so we will not get any pictures or other images, until Dawn re-emerges on the other side into the sunlight. The following website is the one to watch for future info: http://dawn.jpl.nasa.gov/mission/status.asp. The two white spots that are so intriguing are seen on the image at the above link and there is a third image on the far left near the edge of the screen. There may even be others.

Ion propulsion works slowly, takes weeks to build up in space, so is useless for launching to escape velocity, but perfect for the delicate operation of going into orbit around Ceres.

[mal4mac]

Last night I saw Orion constellation. It is easily recognized by its three bright stars close to each other called 'Orion's belt'.

Alnitak, Alniram, and Mintaka - I used to memorise such things when I was 12 :) Just below the belt is the famous Orion Nebula. It's a "fuzziness" that can be seen by the very sharp eyed, and should be obvious in binoculars. It's a vast cloud of gas from which stars are forming as you look - the closest region of massive star formation to Earth.

Might be a good place to send our ion powered robotic self-reproducing spacecraft on their first journey to the stars. Lots of material floating around for them to use!

Orion is a fascinating constellation - it also has two of the top ten brightest stars in the sky. One is Betelgeuse a red supergiant, on the top left shoulder. The other is Rigel at bottom right leg - a blue-white supergiant.

[Dreamwoven]

I agree about Orion constellation, it is very easy to identify by the three stars in a line and the two stars you identify: Betelgeuse and Rigel. Orion is the hunter and its easy to see the Hunter with her bow.

[YesNo]

The link for the Dawn mission called Vesta a "giant asteroid". With Ceres being a "dwarf planet", there must be something that distinguishes these two names. Why is one a dwarf planet and the other a giant asteroid?

[Dreamwoven]

I think that a dwarf planet is round, planet-shaped, while an asteroid of any size is not.

[YesNo]

It isn't very round, but Vesta apparently went through differentiation where the interior heated up and heavy elements sank while lighter elements rose to the surface.

In this video, there is a suggestion that it should be classified as the smallest "terrestrial planet". I also found it interesting that Jupiter's gravity stopped the rest of the asteroids from joining together. It "stirred them up" somehow. http://www.space.com/13902-vesta-asteroid-dwarf-planet.html

[Dreamwoven]

I'm afraid I have really no idea. I didn't even know Jupiter was not part of the solar system until what? something happened. But you can obviously choose yourself how to define vesta, a terrestrial planet or a large asteroid.

[YesNo]

I don't either. But I had never thought of Ceres being a planet before. Or Vesta. Maybe the criteria of having an interior that heated up at one point would quality. However, then the Moon would be a planet.

Although I have not seen the retrograde movement of Jupiter outside, I was able to note the change on the app. I am looking forward to trying to make out Leo outside. The moon is quite bright now and past Leo.

[Dreamwoven]

I agree, except that the moon - perhaps Luna is a better name - is a moon, that is it is captive in the orbit of another planet, Earth.

It was full moon yesterday, I saw it near Jupiter a couple of days before. I am not well up on constellations, Orion and the Plough are the only two I can identify with any confidence.

[free]

The first constellation I could identify was Big dipper. My father showed it to me when I was a child. It is best visible in Apil.

[mal4mac]

I don't either. But I had never thought of Ceres being a planet before....

Ceres isn't a planet, it's an asteroid. Don't listen to those who call it a micro-planet, or whatever, you'll just encourage them. Probably the same people who say Pluto isn't a planet. They are trying to destroy my childhood certainties, and historical precedent, and that's not nice. Don't rock my world by unnecessary reclassification of rocks :)

[mal4mac]

I agree, except that the moon - perhaps Luna is a better name...

The Moon is the Moon, if you go around calling it Luna people will think you are a lunatic :)

[Dreamwoven]

This is an update from the journal blog. (http://dawnblog.jpl.nasa.gov/2015/03/06/dawn-journal-march-6/).

[YesNo]

That was an amazing blog post by Marc Rayman. It looks like ion propulsion works getting Dawn to visit both Vesta and Ceres.

Now to find out what those two bright spots are.

[YesNo]

I just finished reading Bob Berman's article in the April "Astronomy" in the library called "Dark vs super dark". He was commenting on how bright the sky is for most of us. He wrote this about super dark places:


The Milky Way "pops" and totally dominates the sky dome. It casts shadows.

I can barely see the Milky Way, let alone any shadows.

[YesNo]

The nights have been clear and I have been able to see Venus and Jupiter clearly. it is also warmer. According to Sky Map Uranus and Mars were in near conjunction. What amazed me was how high the ecliptic was. Of course, I knew the sun got higher in the sky, but I didn't really think about it before. I am going to try to find Saturn.

[Dreamwoven]

Have you managed to see the Zodiacal light (http://en.wikipedia.org/wiki/Zodiacal_light)? It occurs just after full dark and In the spring it can be seen in the southwest. In the autumn it is a pre-dawn phenomena.

I can't see the spring Zodiacal light. Too many trees in that direction and made impossible by the tall road junction double street corner lights. I will look again in the autumn when it will be pre-dawn and so in the northeast, which should be easier.

The Exozodiacal dust (http://en.wikipedia.org/wiki/Exozodiacal_dust) is the name for the phenomena on other planets.

It is meant to be the sunlight reflected off cosmic dust. In Islam the false dawn of this zodiacal light has an important place in the timing of the five daily prayers. You can read about it here: http://en.wikipedia.org/wiki/Zodiacal_light#Importance_to_Islam.

[YesNo]

I haven't seen the zodiacal light. With the light pollution where I am I would probably not be able to, however, I will keep that in mind as something to look for when I get to Wisconsin later this Spring. Sometimes the skies there are very dark and the "seeing" is clear. I was planning to look for Saturn but I would have to get up early. There is a park I could walk to where it is darker, but I plan to drive to Lake Michigan one of these days and watch the Sun rise.

Trying to find the direction to Mecca (qibla) is an interesting problem. Although I understand the astrolabe would help with this, I don't see how this works. Come to think of it, there is probably an app for the phone that would show this direction.

[Dreamwoven]

This from earth sky (15 March) suggests that Jupiter's largest moon, Ganymede, may have oceans beneath its ice: http://earthsky.org/space/underground-ocean-on-jupiters-largest-moon (http://earthsky.org/space/underground-ocean-on-jupiters-largest-moon)

[YesNo]

Nice article. I didn't know Ganymede had aurorae. That would mean Ganymede has a magnetic field. Although I don't follow how the interference between Jupiter's magnetic field and Ganymede's implies there is an ocean below, it seems plausible. I was amazed at how deep the ocean and ice are predicted to be.

This morning I saw the old moon as the sun rose. I guess we will have a new moon for the vernal equinox.

[Dreamwoven]

Have to agree with that. EarthSky has a post on Ceres (http://earthsky.org/space/dawn-breaks-over-ceres-and-perhaps-signs-of-habitability), I wondered why it was taking so long for Dawn to get better images, it has been in orbit round Ceres for a couple of days or more. It seems it will be gradually going lower in orbit, presumably using its ion propulsion to brake, until it can start to map and investigate the dwarf planet, in a couple of weeks time. Here is a quote:

Fortunately, we won’t have to wait much longer before we get some more definitive answers to questions of Ceres’ physical structure and heritage. By the beginning of April, the Dawn spacecraft will be much closer and will start its imaging campaign in earnest, at which point we will start seeing craters and other surface features at better resolution

[YesNo]

Those two bright spots on Ceres are what interest me the most.

[Dreamwoven]

It might be a long wait…

I've been having a look at Vesta (http://en.wikipedia.org/wiki/4_Vesta), the largest asteroid in the solar system.

[mal4mac]

As I'm writing this I'm watching the solar eclipse in the uk - not total, only 80% where I am. It's 9.45 am GMT here and 80% happened around 9.30, I could see a crescent sun that indeed looked about 20%! The sky was still quite bright - brighter than before the clouds cleared. (I'm amazingly lucky to have seen this, it was forecast to be total cloud cover, but it cleared at just the right time.)

When I realised it was sunny I hurriedly made a simple pinhole camera. "Don't stare directly at the sun, folks," as they keep on saying. To do that use a pin to make a small hole in a piece of photocopy paper, with a pin, than project the image of the sun onto another piece of photocopy paper. The image you get is small (dime size) but you can easily see the moon covering the sun, and the change in the amount of cover, which happens over several minutes.

The birds are making some strange chirping noises. It's definitely getting brighter as the minutes wear on. A dog is barking. The neighbours are giving me strange looks as I manipulate two pieces of photocopy paper into strange positions in my garden...

10am now and the moon is now only covering 50/60% of the sun.

The BBC hired a plane to fly above the clouds and capture totality:

http://www.theguardian.com/science/live/2015/mar/20/solar-eclipse-live-updates

Still my less expensive approach was 80% as good, I reckon, for a lot less than 20% of the effort! It's great to actually go out into your garden and do this rather than watching it on the web. I can say I was there :)

[Dreamwoven]

I saw the partial eclipse too. It got noticeably darker when it happened between 10.50 and 11.05, and the birds went quiet. Animals know its happening, which I find fascinating. I reckon it got 50 percent partial eclipse in Sweden: http://www.thelocal.se/20150320/sweden-gets-glimpse-of-solar-eclipse

[YesNo]

It is interesting that animals may have sensed it. It does get darker.

The last time I saw a total eclipse was almost two decades ago. Many of us were out looking through pinholes in paper but underneath a maple tree we could see projected on the sidewalk many tiny eclipses showing through the leaves of the tree.

[Dreamwoven]

I have jet read about the new James Webb Telescope to be launched in 2018. You can read about it here (http://www.space.com/28921-james-webb-space-telescope-budget.html?cmpid=559183).

[YesNo]

In looking at Wikipedia (http://en.wikipedia.org/wiki/James_Webb_Space_Telescope) this telescope would collect five times as much light and be focused on the infrared. I can see how one can collect more radiation: just build a bigger surface. But I don't know what it means to focus on the infrared. The position of the telescope would be at a Lagrangian point in earth's orbit around the Sun. I suppose it would not be able to be repaired as easily as Hubble in low-earth orbit.

[Dreamwoven]

Good points!

I had also not thought of the problem of making repairs so far out in space.

[YesNo]

I am hoping to see the lunar eclipse tomorrow morning. It would be about 5:16 my time in Chicago. There is a good chance I will be asleep, but I wasn't able to see the solar eclipse a couple weeks ago since it was at night my time.

[YesNo]

It turns out I woke up early enough this morning to see the Moon get almost completely eclipsed before it disappeared in the clouds above my neighbor's house in the west.

I was hoping to see the moonshadows disappear, but dawn made them disappear first.

Also, considering the curvature of the Earth's shadow on the Moon, clearly the Earth is far bigger than the moon. I wonder if there are such things as the Earth's shadow eclipsing outer planets such as Mars and Jupiter. I'll have to look that up. The Earth would not eclipse Venus or Mercury since they are closer to the Sun than the Earth and so the Earth can't get in the way of the Sun's light.

[Dreamwoven]

A lunar eclipse shows the moon as red, as this is the colour that is visible through the earth's atmosphere. See https://en.wikipedia.org/wiki/Lunar_eclipse. I don't think the shadow of the earth projects far enough to eclipse any of the outer planets, but such events certainly happen when the earth comes between the sun and any of its planets.

I found a very nice astronomy blog from Northern Ireland, http://www.armaghplanet.com/blog/ divided up into solar system, our galaxy, universe, and a miscellany category weird and fun. Its well written and very informative. The Armagh Planetarium has its own webpage, too: http://www.armaghplanet.com.

[YesNo]

The article about the solar flyby 70,000 years ago and the four species of humans alive then was pretty interesting: http://www.armaghplanet.com/blog/did-a-wandering-star-light-up-ancient-skies.html

As far as those four species, I knew about the Neanderthal, but not the Denosovan nor Homo floresciensis.

[Dreamwoven]

Yet another probe that I had never heard of - this time Japanese, Akatsuki (https://en.wikipedia.org/wiki/Akatsuki_(spacecraft)) - that missed its orbit around Venus and went round the sun instead. It has also got boost propellent (not sure what kind) but its back and on track for its orbiting around Venus. See also this Astronomy Now (http://astronomynow.com/2015/02/09/japanese-craft-to-get-second-chance-after-missing-venus-in-2010/) piece.

[YesNo]

I had not heard of Akatsuki before either. From the links, it will be looking for lightning and volcanic activity if it gets into orbit around Venus. I wonder why lightning would be of interest. I can see how volcanic activity would show that the planet is still active.

[Dreamwoven]

There seem to be a number of large objects circling the sun between Jupiter and Pluto. This one from space.com is about a Centaur, Chiron:

After its discovery in 1977, Chiron was classified as the first "centaur" — a body between Jupiter and Pluto with characteristics common to both asteroids and comets. Today, there are more than 200 known centaurs, and scientists estimate that there are more than 44,000 of these hybrid asteroid-comets in the solar system.

Thats amazing, Chiron has rings around it, like Saturn. It is large, too, minor planet, comet-asteroid, it is 145 miles wide.

Read more about it here: http://www.space.com/29067-chiron-centaur-asteroid-comet-rings.html?cmpid=NL_SP_weekly_2015-04-13.

[YesNo]

I didn't think rings were common either. It looks like the difference between asteroids and comets is one has more metal and the other has more ice to form tails. I guess the combination has some of both.

[Dreamwoven]

First fuzzy shots of Pluto, from earthsky (http://earthsky.org/space/new-horizons-first-color-pic-of-pluto?utm_source=EarthSky+News&utm_campaign=2fa2f02ccf-EarthSky_News&utm_medium=email&utm_term=0_c643945d79-2fa2f02ccf-394044013):

[YesNo]

Here's a link showing the bright spots on Ceres which may be made of ice: http://www.nature.com/news/mystery-of-ceres-bright-spots-grows-1.17313

[Dreamwoven]

Popular Astronomy sends subscribers email updates from time to time. Some of these are quite interesting. Below is a part of one which is on Mars. Funnily enough Immanuel Velikovsky wrote about this in the 1950s, that Venus was originally a comet (or perhaps a giant asteroid captured by the earth's gravitational pull to bring it into orbit and the clashes with Mars over many generations (I think it was every 50 years) took place until Venus established itself in a separate orbit.

Anyway, I was fascinated by the book on this I read, Earth in Upheaval, as well as the first of two books on how the ancient history of Egypt got muddled up with repeating events 50 years apart (Ages in Chaos).

METEORITE MAY REPRESENT BULK OF MARS' CRUST (http://www.forum.popastro.com/viewtopic.php?f=13&p=107694&sid=7d5eb209c19d8575f142ed1edc9b0b5f#p107694)
Brown University
NWA 7034, a meteorite found a few years ago in the Moroccan desert, is like no other rock ever found on Earth. It has been shown to be a 4.4-billion-year-old piece of the crust of Mars and, according to a new analysis, rocks just like it may cover vast swaths of Mars. In a new paper, scientists report that spectroscopic measurements of the meteorite are a spot-on match with measurements from orbit of the Martian dark plains, areas where the planet's coating of red dust is thin and the rocks beneath are exposed. The findings suggest that the meteorite is representative of the 'bulk background' of rocks on the Martian surface. When scientists started analyzing the meteorite in 2011, they knew that they had something special. Its chemical make-up confirmed that it came from Mars, but it was unlike any other Martian meteorite. Previously, all the Martian rocks found on Earth were classified as SNC meteorites (shergottites, nakhlites, or chassignites). They are mainly igneous rocks made of cooled volcanic material, but the new object is a breccia, a mash-up of different rock types welded together in a basaltic matrix. It contains sedimentary components that match the chemical make-up of rocks analyzed by the Mars rovers. Scientists concluded that it is a piece of Martian crust -- the first such sample to be found on the Earth.
Scientists thought it might help to clear up a long-standing enigma: spectra obtained from SNC meteorites never quite match remotely-sensed spectra from the Martian surface. So after acquiring a chip of the meteorite, they used a variety of spectroscopic techniques to analyze it. The researchers say that the spectral match suggests that the 'dark plains' on Mars are dominated by brecciated rocks similar to the new meteorite. Because the dark plains are dust-poor regions, they are thought to be representative of what lies beneath the red dust on much of the rest of the planet. The researchers claim that, in the light of what is known about Mars, the idea that the surface would be rich in such breccias makes sense. Mars has more than 400,000 impact craters more than 1 km in diameter. Because brecciation is a natural consequence of impacts, it is to be expected that material similar to NWA 7034 has accumulated on Mars over time. In other words, many of the rocks on the surface of Mars are probably very similar to the meteorite.

[Dreamwoven]

The first 3 volumes of Velikovsky were Worlds in Collision (about Mars and Venus as Venus jostled with Mars to clear her orbit, Earth in Upheaval looking at the evidence for violent upheavals on earth, and Ages in Chaos, which look at periods of history which historians unwittingly duplicated. The first was From the Exodus to King Akhnaton which deals with the Israeli exodus and crossing the Red Sea when the waters part. The book is very scholarly and I am not able to judge it as I can't read the Old Testament Book of Exodus in its original Hebrew, but it seems to me that he makes a case for the fact that scholars made an erroneous duplication of ancient history, based on the series of plagues and the violent physical upheavals in the Middle East. I have not read Vol. 2 of Ages in Chaos: Ramses II and His Time but the 2 volumes put the case for a double-counting of the plagues and upheavals that were the results of the periodic Mars-Venus near-collisions. Another Volume Mankind in Amnesia explains the disjunction as a collective amnesia on the part of historians of the time.

Velikovsky's massive work was subject to a storm of critique and led to the banning of his books by so many prominent historians of the time that the publishers caved in and withdrew the books from publication. This was the 1950s when the Cold War was at its height. But I also read Alfred De Grazia The Velikovsky Affair (published in 1966) which attempted to defend Velikovsky. The worst period of McCarthyism was over but the damage had been done by then.

His works have been re-published in their original entirety in 2009 (paperbacks) by Paradigma Books.

[YesNo]

I had not thought of Venus being originally a comet or asteroid before. It is even amazing to me that brecciated rocks from Mars' surface can reach the Earth. Although Velikovsky's view seems unusual, one way to check it is to see how long ago Venus was recognized in the sky as a planet.

[Dreamwoven]

Yes, that is one way. Velikovsky goes into this in some detail. The 4 planet system - Saturn, Jupiter, Mars, Mercury - were identified in the ancient hindu table of planets, Venus was not there (planet in Greek means "wanderer", as the planets did not follow the stable pattern of the sun and moon). Later they realised that this was because they don't go round earth as they at first believed but round the sun. Venus was a comet as it had a "tail", it "smoked".

That is it in a nutshell.

[YesNo]

It looks like Velikovsky's theory passed my initial attempt at falsification. It makes me wonder what those early Hindus thought about Venus.

[cacian]

Last night I saw Orion constellation. It is easily recognized by its three bright stars close to each other called 'Orion's belt'.

i wonder why belt
this is usually something you buckle
or the expression
a belter
but three to form a belt is rather strange

[Dreamwoven]

The belt is just one obvious part of the constellation of Orion (the hunter) which looks a bit like an archer shooting a bow. The belt is very distinctive, and the easiest to distinguish. I can't find an image of the entire constellation, but this one (http://www.space.com/13924-orion-constellation-nebula-skywatching-tips.html) of the belt and the armpit of Orion (Betelgeuse) is the best I can find atm.

[Dreamwoven]

OK I found it, middle picture here. (http://amazing-space.stsci.edu/news/archive/2006/01/ill-01.php)

[cacian]

The belt is just one obvious part of the constellation of Orion (the hunter) which looks a bit like an archer shooting a bow. The belt is very distinctive, and the easiest to distinguish. I can't find an image of the entire constellation, but this one (http://www.space.com/13924-orion-constellation-nebula-skywatching-tips.html) of the belt and the armpit of Orion (Betelgeuse) is the best I can find atm.
thanks i find the names given rather hidden.

[cacian]

OK I found it, middle picture here. (http://amazing-space.stsci.edu/news/archive/2006/01/ill-01.php)

I am not quite sure why hunter exactly but there you go each to their dreams.:)

[Dreamwoven]

I agree, it is a bit Rorschach-like and why the lines are drawn between stars they way they are is never explained. Bt seeing the whole of the Orion constellation I can see the left arm raised and two stars being the fingers of the left arm, after loosing an arrow. Orion also has 2 hunting dogs - Canis Major and Canis minor (http://www.constellation-guide.com/constellation-list/canis-major-constellation/). I can't for the life of me see a dog in either of these constellations. Canis Major includes the brightest star in the heavens, Sirius.

But how they work out the names of the constellations is beyond me.

[Dreamwoven]

The text below is from the Society for Popular Astronomy. It shows the extreme violence of interstellar space.

At our London meeting this Saturday, 25 April, our Vice President, Prof. Tim O'Brien, will talk about novae – exploding stars.
Several times each year a new star appears in the night sky. Dubbed novae by astronomers of the past, we now know these are explosions on white dwarfs in binary star systems which can eject around an Earth’s mass of material into space at speeds of thousands of kilometres per second. The white dwarf is not destroyed in these outbursts and the nova lives to explode again – in some cases within the lifetime of a single astronomer.
Novae are now detected right the way across the spectrum from radio waves to gamma rays. Prof. O'Brien will describe the latest observations and what they teach us about these interesting astrophysical phenomena – stellar explosions that are sometimes visible to the unaided eye from our own backyards!
This replaces the talk by Dr Lewis Dartnell previously advertised.
Following the break, Robin Scagell talks about forthcoming events in the night sky, and Dr David Mannion looks at The Future of Space Travel. Where will we go after the tremendous Apollo missions, the Mars Rover and the exploration of our Solar System by interplanetary robots? Will we have bases on the Moon and Mars by the end of the 21st Century?
The meeting takes place at SOAS, University of London, starting at 2 pm. More details, and a map of how to get there, are given on the SPA website.

[YesNo]

I would think that a nova would destroy any planets with life in nearby solar systems. I wonder if binary star systems are needed for these novas to occur.

[Dreamwoven]

The Lunar Reconnaissance orbiter (http://lunar.gsfc.nasa.gov/mission.html) is another of those quiet missions that rarely gets a mention on the news. This post on earthsky (http://earthsky.org/space/lunar-reconnaissance-orbiter-drops-nearer-moon) said that the orbiter has gone into a very low orbit (12 miles above the surface) to explore and map the dark side of the moon.I will work at this height for some time:
"Team members made the decision to change the orbit after determining that the new orbit configuration poses no danger to the spacecraft. They say LRO can operate for many years at this orbit."

[Iain Sparrow]

I would think that a nova would destroy any planets with life in nearby solar systems. I wonder if binary star systems are needed for these novas to occur.

Yes indeed, a nova would exterminate all organic life in that solar system.
If memory serves, supernovas occur more often in binary systems, only because the needed mass threshold is more likely with two stars; one star pulling material away from the other. But solitary stars explode too, if large enough.

[Iain Sparrow]

The Lunar Reconnaissance orbiter (http://lunar.gsfc.nasa.gov/mission.html) is another of those quiet missions that rarely gets a mention on the news. This post on earthsky (http://earthsky.org/space/lunar-reconnaissance-orbiter-drops-nearer-moon) said that the orbiter has gone into a very low orbit (12 miles above the surface) to explore and map the dark side of the moon.I will work at this height for some time:
"Team members made the decision to change the orbit after determining that the new orbit configuration poses no danger to the spacecraft. They say LRO can operate for many years at this orbit."


I think the problem is that mapping the dark side of the Moon, just isn't 'sexy' enough for the nightly news.

[YesNo]

I was also looking for more information about Ceres, but I couldn't find anything new. Yes, the dark side of the moon isn't as sexy as those bright spots on Ceres.

[Dreamwoven]

I've continued each day to check the NASA Dawn website, too. Nothing so far. I think that, like the moon orbiter, it may be able to make out more detail once its orbit is low enough. Obviously, orbiting such a small planet it will take time to get into the lowest orbit.

[Dreamwoven]

You may be right, Iain, the moon is not attractive enough for a news bulletin. I think the moon orbiter is looking for frozen water, hence the south pole of the moon.

[Dreamwoven]

4-inch cubesats (http://www.space.com/29306-cubesats-deep-space-exploration.html?cmpid=NL_SP_weekly_2015-05-11) for exploring deep space.

[YesNo]

Here is a new picture of Ceres. It looks like the larger reflective surfaces are composed of smaller ones: http://www.nbcnews.com/science/space/ceres-spots-shine-new-images-dwarf-planet-n357161

[YesNo]

4-inch cubesats (http://www.space.com/29306-cubesats-deep-space-exploration.html?cmpid=NL_SP_weekly_2015-05-11) for exploring deep space.

Just when I thought bigger was better, it looks like small has advantages as well.