Astronomy

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.

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, Laika, the first dog in space and 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.

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.

Quote:

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Originally Posted by 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.

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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.

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.

I've checked up about the moon, there is Wikipedia posts on the Great Moon Hoax, meaning that in 1835: here. NASA 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.

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.

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.

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.

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, a good one this year it seems.

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.

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).

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.

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, a denizen of the distant Kuiper Belt.

There is still controversy over Pluto's status and presumably also of Charon, 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 for much of what I have learned of Pluto and the other dwarf planets.

What do you make of all this?

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?

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 makes this clear.

The Winter Solstice is the time to watch the Ursid Meteors, as EarthSky have explained. Meteors display at radiant points. There is a full catalogue of meteor showers at http://earthsky.org/astronomy-essent...r-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

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.

The one you saw in the mid-1980s was probably Halley. 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 Cometography is run and maintained by Gary W. Cronk and is remarkably comprehensive. I may make comets one of my special interests.

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.

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

Space.com has written about NASA's attempt to capture an asteroid and put it in orbit around the Moon. The idea being to study it. Won't be for a few years but should be interesting.

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.

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.

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.

Space.com has a post on Ceres, wondering whether it can support life. This is the post: http://www.space.com/28068-dwarf-pla...l?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. 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 problematic. Planet, dwarf planet, asteroid, have all been considered by the International Astronomy Union, generally recognised as the world authority in such issues.

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.

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 after launch in 2006. The journey of 9 years is something of an epic in itself, needing several 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.[26] (Pluto, Wikipedia)

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

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.

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.

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.

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.

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.

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.

Comet Lovejoy looks to be showing well this month. I subscribe to Eagleseye (an Englishman's blog ) and just received a post just published which give some info and a picture of the comet.

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.

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.

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.

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.