Astronomy

[Dreamwoven]

http://earthsky.org/space/how-hard-did-it-rain-on-mars? Applying knowledge of rain on earth to Mars long ago.

[desiresjab]

This is the clearest explanation I have found of the Big Bang Theory:

https://www.universetoday.com/135791/cosmic-inflation-quest-understand-earliest-universe/

This one contained a shock! I had always thought the diameter of the universe grew to at least several hundred thousand light years during Cosmic Inflation.

One must adjust. It is hard to wrap one's ears around the scale visually. Yes, the diameter of the universe did increase by a hundred septillion times during inflation. However, starting out smaller than an atom, this only brought its diameter up to almost a thousandth of a meter. The mind must have a sense of how small atoms really are to make this increase seem stunning. The fact that the increase seems to have occurred in about an octillionth of a second (or somewhere in that neighborhood) can add to the effect of just how dramatic it was--to increase your size by a factor of a hundred septillion--but in an octillionth of a second. Now that's moving!

[Dreamwoven]

Mind-boggling argument:
https://www.universetoday.com/135922/know-universe-flat-discovering-topology-universe/

[desiresjab]

Mind-boggling argument:
https://www.universetoday.com/135922/know-universe-flat-discovering-topology-universe/

Yeah, it is mind boggling. To feel secure, one would have to understand why curvature would produce distortions in the heat signature. I am not pysicist enough to say. I get the geometrical idea--I can see how the surface you are traveling affects how many 90 degree turns are required to arrive back at your starting place. That is the first time I have seen a good explanation of what astronomers are implying when they say the universe is "flat."

[Dreamwoven]

Yes, desiresjab, thats where I get to, too, four 90 degree turns take you back to where you started...

[Dreamwoven]

https://www.space.com/35329-making-giant-magellan-telescope-massive-mirrors.html

[Danik 2016]

Impressive images of the telescope, DW! Filmed in scientific fiction mood!

[Dreamwoven]

Everything you have wanted to know about the Taurid asteroids (this time of year):

https://mg.mail.yahoo.com/neo/launch?.rand=5it4l8mg8drh3#5985

[Dreamwoven]

https://www.universetoday.com/136044/sun-probably-lost-binary-twin-billions-years-ago/

[YesNo]

If our solar system originally had two suns, I wonder what star would be the candidate for our sun's binary.

[Dreamwoven]

https://www.universetoday.com/136060/elon-musk-details-vision-human-civilization-mars/

[Dreamwoven]

https://www.space.com/37242-nasa-kepler-alien-planets-habitable-worlds-catalog.html

[Danik 2016]

A curious opinion:
Hawking urges Moon landing to 'elevate humanity'
"We are running out of space and the only places to go to are other worlds. It is time to explore other solar systems. Spreading out may be the only thing that saves us from ourselves. I am convinced that humans need to leave Earth," the Cambridge University theoretical physicist explained.
http://www.bbc.com/news/science-environment-40345048

Dry comment: Having ruined the earth we are ready to go to other parts of the universe.

[YesNo]

I don't think we ruined the earth yet, but a correction is needed.

I suspect we will get to the Moon and Mars after a thousand years of robotic exploration and habitat building or terraforming. The interest in sending human beings now before a habitable environment has been built puzzles me. There is something socio-psychological underlying this desire that I find questionable.

[Danik 2016]

I think the urge of sending men to space is similar to the one that made the European navegators discover new continents.

[Dreamwoven]

https://www.universetoday.com/136060/elon-musk-details-vision-human-civilization-mars/

“You would ultimately have upwards of 1,000 or more spaceships waiting in orbit. Hence, the Mars Colonial fleet would depart en masse. It makes sense to load the spaceships into orbit because you have got 2 years to do so, and then you can make frequent use of the booster and the tanker to get really heavy reuse out of those. With the spaceship, you get less reuse because you have to consider how long it is going to last—maybe 30 years, which might be perhaps 12–15 flights of the spaceship at most.”

[tailor STATELY]

Cool. Mars is the sweet spot for our New Earth, but so many concerns, especially radiation effects on the human system.

Other possibilities in this wiki https://en.wikipedia.org/wiki/Space_colonization.

Ta ! (short for tarradiddle),
tailor STATELY

[Dreamwoven]

The Moon is already going to have small permanent bases on it from various countries.

[Dreamwoven]

A new moon going round a small planet in the Kuiper Belt has recently been discovered by the Kepler Space Telescope: https://www.universetoday.com/136123/astronomical-detective-tale-moon-2007-or10/

[Dreamwoven]

https://www.universetoday.com/136174/snake-rovers-might-best-way-explore-surface-tunnels-mars/

several interesting issues in this post.

[YesNo]

I like the idea of that snake robot and the focus on robotics rather than human exploration.

[tailor STATELY]

For the earthbound of today, to inspire the explorers of tomorrow... http://lockheedmartin.com/generationbeyond/mars-experience

[YesNo]

That virtual reality bus is how humans should be experiencing Mars or other planets when robots are improved enough to do this exploration for us. They are our telescopes onto these objects.

One of the things we seem to ignore about Earth is that it has a magnetosphere. It is known that this protects us from radiation and so we need to protect ourselves against radiation in space, but it probably also provides us with our sanity; our hearts resonate with it. I am getting this idea from some research by HearthMath Institute: https://www.heartmath.org/research/featured-research/

[Danik 2016]

Not so good news to those eager to move to Mars:

Mars may be more toxic to life than we thought

"Life on Mars … does it exist? Depending on when you last checked in with news about the Red Planet, you could probably be convinced either way. As we discover more and more about the composition and planetary dynamics of Mars, there has been cause for both elation and disappointment regarding the likelihood that organic life could manage to eke out a living on the planet."

http://www.astronomy.com/news/2017/07/mars-perchlorates-bacteria

[YesNo]

I was hoping they would find life on Mars, but maybe this shows that there isn't any life there.

The Event Horizon Telescope has come up in some readings about gravitation: http://eventhorizontelescope.org/blog/eht-update One of their goals is to measure the shadow of a black hole or "grey star" as viewed by modified gravity (MOG). There are two separate predictions about the value of the measurements. This could be a way to tell if there really are black holes (points with infinite mass and event horizons) or if they are grey stars, bodies that have not collapsed to a point but are kept stable by a fifth force.

[Danik 2016]

I think the point about all these experiments and speculations is to get more familiar with space and eventually find an habitable planet for us humans.

Missing DW. He hasn´t been around for some days. And he used to be a "regular".

[Danik 2016]

Tracking the birth of a 'super-earth'

"Kepler has found thousands of planets, but those are all very old, orbiting around stars a few billion years old, like our sun," he explains. "You could say we are looking at the senior citizens of our galaxy, but we don't know how they were born."

https://www.sciencedaily.com/releases/2017/07/170711092823.htm

[YesNo]

I haven't seen DW either. I suspect we have hundreds of millions of years before we would need another planet. The problem would be the earth getting too close to the sun and turning into a planet like Venus. We might be able to solve that problem as well with shielding of some sort.

[Danik 2016]

All is possible, Yes/No.

"Astronomers just discovered the smallest star ever

While on the search for exoplanets, the team came across this tiny companion."
http://www.astronomy.com/news/2017/07/tiny-new-star

[YesNo]

A star about the size of Jupiter (but 85 times more massive) does seem small. I've heard that Jupiter could have been an early star that burnt out to make our system binary. Here's something about that from a quick search: https://www.scientificamerican.com/article/i-have-heard-people-call/ Based on that article, apparently not. It is not massive enough to have once been a star.

[Danik 2016]

Fascinating article Yes/No.
"Stellar formation is a hot topic of current research, as astronomers are trying to fathom the still-mysterious details of the birth process."
This is a topic that interests me specially because it shows how much astronomy has developed in the last years. Stellar formation will eventually lead to the discovery of an similar to earth planet. Perhaps it might also help to preview future interplanetary disasters. Anyway the universe of astronomy is expanding fastly.

[Danik 2016]

The Space-Age Origins of 'Planet of the Apes'

"The famous 1968 film that kicked off the movie franchise — "Planet of the Apes," starring Charlton Heston — began with astronauts crashing into an unknown planet. A rebooted series in 2001, starring Mark Wahlberg, starts off with astronauts and apes working together, exploring space in the future."
https://www.space.com/37476-planet-of-the-apes-space-origins.html

[YesNo]

Besides the disaster that might have happened on Mars that you mentioned earlier, Venus got too close to the sun and that triggered the greenhouse gases. I wonder how one could make Venus habitable? The reason to think of that is because Earth will get closer to the Sun than it is now and could suffer the same fate (but that is many years in the future). If we can make Venus habitable, we can keep Earth habitable for longer.

[Danik 2016]

Venus is probably to hot to be habitable. But possibly they will find some new planets and one or several of them might be habitable.

[Danik 2016]

Venus is probably to hot to be habitable. But possibly they will find some new planets and one or several of them might be habitable.


Planet Nine hypothesis supported by new evidence

"Last year, the existence of an unknown planet in our Solar system was announced. However, this hypothesis was subsequently called into question as biases in the observational data were detected. Now Spanish astronomers have used a novel technique to analyse the orbits of the so-called extreme trans-Neptunian objects and, once again, they point out that there is something perturbing them: a planet located at a distance between 300 to 400 times the Earth-Sun separation."
https://www.sciencedaily.com/releases/2017/07/170712110457.htm

[YesNo]

Venus is too hot and that is likely the destiny of the Earth in a billion years as it gets closer to the Sun. However, one might be able to cool Venus and heat up Mars and with that knowledge regulate the temperature of the Earth. We have millions of years to figure this out.

The alternative of going to another star system seems even more unlikely than regulating the temperature of these planets near us, however, in a million years, I suspect we will know more about who is out there and perhaps make real contact with them. We may even pay them a visit.

[Danik 2016]

Much earlier I think, Yes/No. Sometimes things go at a fast pace. Who would imagine something like a PC sixty years ago? And now it´s part of our every day life.

Nice to "meet you". I was working on a document inside my inbox and saw your posts on coming out. On Sunday evenings LitNet has become a desert more than ever.

[Danik 2016]

Signals or not signals?

https://www.youtube.com/watch?v=EltmHVQzxqk

[YesNo]

Ross 128 is interesting. I hope it is aliens. :) At 11 light years away, I wonder how long it would take for an exploratory mission to reach that star?

[Danik 2016]

"Jill Tarter has been asking the big question, “Are we alone in the universe?” since she was a child."

http://www.astronomy.com/news/2017/07/jill-tarter-seti-search

[YesNo]

Intelligent life should include plant life. They may not be sending messages to us or those messages may not have reached us yet. However, I am disappointed that something hasn't been observed by now. It is a lot like not finding dark matter. Not finding dark mater makes me suspect there isn't any. Not finding life that is sending us a signal may suggest there isn't any out there at least not in our galaxy. It may also be that our instruments are not sensitive enough to pick up the messages.

[Danik 2016]

I agree with you. I suspect there may be animals, plants and even spirit worlds out of the reach of our perception and our instruments.

[Danik 2016]

Astronauts on the Space Station Will See the Solar Eclipse 3 Times (Video).
"When the Great American Solar Eclipse sweeps across the continental U.S. on Aug. 21, astronauts aboard the International Space Station (ISS) will have a chance to see it from a unique vantage point."
https://www.space.com/37651-solar-eclipse-2017-space-station-randy-bresnik-video.html

[YesNo]

I hadn't thought about the view those on the space station would have of these kinds of events.

[Danik 2016]

Article about the interaction between celestial bodies. It seems that Golias is going to get the best.

"Galactic David and Goliath
Date:
July 27, 2017
Source:
ESA/Hubble Information Centre
Summary:
The gravitational dance between two galaxies in our local neighbourhood has led to intriguing visual features in both as witnessed in this new NASA/ESA Hubble Space Telescope image. The tiny NGC 1510 and its colossal neighbour NGC 1512 are at the beginning of a lengthy merger, a crucial process in galaxy evolution. Despite its diminutive size, NGC 1510 has had a significant effect on NGC 1512's structure and amount of star formation."
https://www.sciencedaily.com/releases/2017/07/170727103008.htm

[Danik 2016]

"Breakthrough Starshot takes its first step toward interstellar travel

The first big step to making humans an interstellar species is underway."

http://www.astronomy.com/news/2017/08/starshot-sprites

[YesNo]

Those Starshots sound promising using a laser to power them to 20% the speed of light. If such probes can measure gravity along the way they could be used to verify if Einstein or Moffat's gravity theory is accurate. Within the solar system the differences are apparently too small to detect.

[Danik 2016]

I don´t know Moffat´s gravity theory and I have only a very faint remembrance of Einstein´s. But I think there are strong differences of gravity out there. I don´t know how they will influence those theories.

[YesNo]

I didn't think those Starshots existed except as a wild speculation, but it looks like they are possible even if they are only small probes. Dreamwoven mentioned tiny satellites as well but I don't remember them reaching such speeds.

[Danik 2016]

"With the total solar eclipse on Aug. 21 only a few weeks away, astronomers have revealed what skywatchers can expect to see as the sun disappears behind the moon."

https://www.space.com/37710-total-solar-eclipse-structure-sun-corona.html

[YesNo]

The Sun's magnetic field looks interesting. It is at this time the Moon is new unlike now when it is almost full. During a full Moon, the Moon crosses the Earth's "magnetotail" for about six days. The other time it is not in the magnetosphere. It makes me think that there might be a justification for the belief that during a full Moon some people get a bit loony.

[Danik 2016]

I think the word lunatic comes from "luna"(moon). Here in Brasil there is also a legend according to which the werewolf assumes his wolf form on full moon nights.

[YesNo]

Yes, it does come from the Latin for moon. It is at the full moon when it flares it. It occurred to me a justification for such a view would be a magnetic one with the Moon passing through the Earth's magnetosphere (or magnetotail as it is called) for six days around the full Moon. I think it has been shown that we and other animals are affected by the magnetosphere. The moon disturbs that by passing through it.

[Danik 2016]

Interesting simulationS of the magnetic field of the sun:

https://www.nasa.gov/feature/goddard/2016/understanding-the-magnetic-sun

[YesNo]

Nice video of the magnetic aspects of the sun.

[Danik 2016]

Storms seem to be different on Neptun:

http://www.sci-news.com/astronomy/neptune-giant-bright-storm-system-05108.html

[Danik 2016]

Is this the first picture of an eclipse?
Professors found a petroglyph of a total solar eclipse in New Mexico.

http://www.astronomy.com/news/2017/08/total-eclipse-petroglyph

[YesNo]

It is interesting that less carbon-14 means more sunspots. I didn't know there was a connection between them.

[Danik 2016]

Neither did I.

A new hot Neptune may be a massive water world
HAT-P-26b is a steamy, steamy world.
http://www.astronomy.com/news/2017/05/hat-p-26b-may-host-water

I was thinking of the Narrator in FREI´s story, who identifies himself with Neptune.
But calling a new found planet HAT-P-26b is absolutely anticlimatic.

[YesNo]

The "hot ice" mentioned in that article is interesting. I didn't know water could be hot and solid at the same time.

[Danik 2016]

Neither did I. I think these space discoveries are challenging the laws of Physics and Chemistry we learned back in the 20 C.

[Danik 2016]

System of super-Earths discovered around a nearby star

A new study suggests that the system has at least four planets, and two of them orbit on the edge of their habitable zones — the region where liquid surface water might exist. All four are likely super-Earths, and some could potentially even be as big as Neptune.

http://www.astronomy.com/news/2017/08/system-of-super-earths-discovered-around-a-nearby-star

[YesNo]

Apparently there is another technique, "radial velocity method", rather than transits of the planet across the star to find exoplanets. All of this makes me think that we haven't found alien life yet because we haven't got enough precision in our measurements. We don't even know all the planets around our sun assuming there is a Planet X out there.

[Danik 2016]

Your scientific perspective is very valuable because it makes you notice aspects that escape those like myself who have not studied higher Maths or Physic.
As things are developing, it seems there might not only be a planet "X" somewhere in reach of us but also planets "Y", "Z"...

These discoveries surely lead to a revision of the parameters of measurement and evaluation. When I read these articles I get the feeling that the known part of the universe is expanding while the earth and the known part of the solar system are getting smaller and smaller.

[YesNo]

I can follow the math but the physics and chemistry are more mysterious. I have to take the word of survey articles assuming they convince him that they are on the right track. Many of them aren't. One of the things I like about Moffat is that he is empirical. When he is shown wrong he changes his speculations. For example he didn't think there was a Higg's boson, but acknowledged it once found. His theoretical physics is falsifiable although it may be difficult to set up the experiments. Some speculations I've read do not appear to be so, such as, speculations about "many worlds", "string theory", "landscapes", "artificial intelligence" or the "anthropic principle". The question underlying these speculations is not physics but why are people even coming up with these ideas? What is the cultural driver? Jonathan Haidt seems to suggest it is "rationalism" which had its root around Hume's time (although Hume was opposed to it) and may be ending as a culturally accepted belief today.

Regarding Planet X, Y or Z, it is good for people to realize that scientists don't know as much as the media suggests they do. We need more empirical evidence. I like the idea of those tiny space probes that can be accelerated rapidly.

[Danik 2016]

I haven´t read any of these space theories. My interest for astronomy comes from two sources: one is a children´s book from Brazilian author Monteiro Lobato called Viagem ao Céu(A trip to heaven) from 1932, which takes his character´s on a trip through the Astronomical heaven then known.
The second source of inspiration is astrology, because of it´s relation to the planets of the solar system.
A third source is this thread. I´ll have a look at Moffat. My own guess about all these speculations is that the human urge to dominate space has increased in the last decades. It reminds me very much of the theories the Europeans had about the ocean and other continent at the beginning of the period of the Great Navigations,

[Danik 2016]

Total Solar Eclipse Aug. 21, 2017: Live Webcasts from NASA

https://www.space.com/17933-nasa-television-webcasts-live-space-tv.html

[YesNo]

Other planets and our ability today to send probes to them give us something to do like the Great Navigation must have done. It is a challenge that did not exist in the past.

[Danik 2016]

I think it is the same thirst for discoveries bound up with the impulse to dominate the unknown regions of space.

[Danik 2016]

Another fascinating discovery:

Uranus and Neptune: Cloudy with a chance of diamonds

"On Earth, we experience rain composed of liquid water. On Titan, it rains liquid methane. And on Uranus and Neptune, it rains solid diamonds. For the first time, researchers have now simulated and observed this process here on Earth, proving that this long-held assumption is likely correct, once and for all."
http://www.astronomy.com/news/2017/08/researchers-recreate-diamond-rain

[YesNo]

Raining diamonds is amazing.

[Danik 2016]

Some of this eclipse pictures are amazing. Enjoy yourselves:

http://www.skyandtelescope.com/astronomy-news/best-2017-solar-eclipse-pictures-from-our-readers/

[YesNo]

The prominences were most striking for me. I wonder what happens on the earth during that time? I have heard animals and insects behave differently, but I wonder if there is changes in the magnetosphere during that time.

[Dreamwoven]

[QUOTE=Danik 2016;1342081]Another fascinating discovery:

Uranus and Neptune: Cloudy with a chance of diamonds

"On Earth, we experience rain composed of liquid water. On Titan, it rains liquid methane. And on Uranus and Neptune, it rains solid diamonds. For the first time, researchers have now simulated and observed this process here on Earth, proving that this long-held assumption is likely correct, once and for all."


I saw this, too, and yes it is amazing. I believe it was posted in earth/sky, and relates to Saturn's moon Titan, though i can't find the link.

[Dreamwoven]

I think the link is from a total eclipse from USA, refers to the moment when a diamond ring phenomenon is created.

[YesNo]

Welcome back Dreamwoven! I thought that diamond ring was what the sunlight looked like around the moon just prior to the totality of an solar eclipse.

I heard somewhere during commentaries on the eclipse that being able to see a total solar eclipse may be rare in the universe, although what that probability is can't be determined at the moment. It requires having a moon large enough to block out the sun completely.

[Danik 2016]

[QUOTE=Danik 2016;1342081]Another fascinating discovery:

Uranus and Neptune: Cloudy with a chance of diamonds

"On Earth, we experience rain composed of liquid water. On Titan, it rains liquid methane. And on Uranus and Neptune, it rains solid diamonds. For the first time, researchers have now simulated and observed this process here on Earth, proving that this long-held assumption is likely correct, once and for all."


I saw this, too, and yes it is amazing. I believe it was posted in earth/sky, and relates to Saturn's moon Titan, though i can't find the link.

I didn´t find the link you mentioned either, but found this older article about Titan, that´s interesting too:

"More life keys in Titan’s atmosphere

A short synopsis of two announcements of new discoveries of organic molecules in the thick atmosphere of Saturn’s moon Titan."

[Dreamwoven]

Danik, can you provide the link to the Titan article. Thanks.

[Dreamwoven]

Welcome back Dreamwoven! I thought that diamond ring was what the sunlight looked like around the moon just prior to the totality of an solar eclipse.

I heard somewhere during commentaries on the eclipse that being able to see a total solar eclipse may be rare in the universe, although what that probability is can't be determined at the moment. It requires having a moon large enough to block out the sun completely.

Thanks, YesNo, I'm glad to be back. Yes that is my understanding, too. It just so happens that the moon is precisely the right size to create the diamond ring effect, as you say, just prior to a total eclipse.

[Danik 2016]

Sorry, people. I forgot to provide the link.
Here you are:

http://earthsky.org/space/saturn-moon-titan-atmosphere-organic-molecules-discovery

[Dreamwoven]

Thanks, Danik. I can't find any reference to diamonds in earth sky.org, but I still feel I had read something about this in a post somewhere.

[Danik 2016]

DW
I found several references to the "diamond rain", though I didn´t look specifically in earth.sky. org. Most of the links I found are from former years, so you must have read about it indeed.

Here is a recent link about scientists recreating the diamond rain in a lab:

https://phys.org/news/2017-08-scientists-diamond-interior-icy-giant.html

[Dreamwoven]

Thanks for the link, Danik. This is pretty good. The article talks about diamond rain as being far inside the icy planets and their moons, so its about right I would say.

[Danik 2016]

Again it seems that the physical concepts we learned at school, don´t work for other celestial bodies.

"A new hot Neptune may be a massive water world
HAT-P-26b is a steamy, steamy world."

http://www.astronomy.com/news/2017/05/hat-p-26b-may-host-water

[Dreamwoven]

That's right. There is clearly a huge diversity of planets, they can't be classified by what we have in the solar system.

[Dreamwoven]

Watch Asteroid "Florence" as it glides past Earth: https://www.universetoday.com/136981/watch-asteroid-3122-florence-zip-past-earth-weekend/. It is pretty big, about 4.4 kilometres across. No danger of it crashing on earth, though.

[Danik 2016]

Florence looks quite impressive. I hope it behaves well.

[Dreamwoven]

I'm pretty sure it will, its a long way from Earth and these days close attention is paid to all sizeable space rocks caught in orbit of the sun.

[Dreamwoven]

The Centre for Near-Earth Object Studies at NASA is an organisation that follows this: https://cneos.jpl.nasa.gov/news/news198.html

[Dreamwoven]

It is not clear how this sub-unit of NASA works. It may only have a couple of people keeping it going, with more drawn in if there should be an emergency. And does it consults with a Russian equivelent? Just a few years ago there was a meteor that grazed low over a Russian town. See the Chelybinsk Meteor: https://en.wikipedia.org/wiki/Chelyabinsk_meteor. In 1908 a large area of Russian forest was flattened: see https://en.wikipedia.org/wiki/Tunguska_event. This would be a good area for US/Russian collaboration.

[Danik 2016]

Neither do I, DW. I only imagine that keeping this units must cost a lot of money.
I also have no idea about how the colaboration of astronomers US/Russia is today.

Just found this:
https://www.scientificamerican.com/article/u-s-and-russia-may-explore-venus-together/

So there is some colaboration.

[Dreamwoven]

That was in interesting link, Danik. The USSR sent several probes to Venus before the USSR collapsed. So its a good thing to see the research continued in collaboration between Russia and the USA.

[Danik 2016]

Specially considering the current international political positions of both countries, I think.

[Dreamwoven]

Absolutely!

[Dreamwoven]

https://www.universetoday.com/137023/ultraviolet-light-point-way-life-throughout-universe/

[Danik 2016]

Interesting study on the biological importance of UV-rays. It is part to what I call "finding the way to the celestial India" because this all reminds me so much of the aims of the Great Navigations, when the Europeans found there way around in the oceans and eventually discovered other continents.

[Dreamwoven]

Ultra-violet light is particularly important for humans just as it says in the universe today website: https://www.universetoday.com/137023/ultraviolet-light-point-way-life-throughout-universe/

[Danik 2016]

To be sure!
Here is another recent article that impressed me:

What lit up the universe? Black holes may have punctured darkened galaxies, allowing light to escape

Date:
August 30, 2017

Source:
University of Iowa
Summary:

Researchers have a new explanation for how the universe changed from darkness to light. They propose that black holes within galaxies produce winds strong enough to fling out matter that punctures holes in galaxies, allowing light to escape.
https://www.sciencedaily.com/releases/2017/08/170830114800.htm

[Dreamwoven]

Well, that was an unusual theory. We need more research to buttress the theory.

[Dreamwoven]

And here it comes:
Universe Today has two postings on the Milky Way's massive double black holes, and a theory of how the universe became filled with light, many eons after the Big Bang:

https://www.universetoday.com/137062/another-monster-black-hole-found-milky-way/

https://www.universetoday.com/137048/universe-filled-light/

[Dreamwoven]

Universe Today has two postings on the Milky Way's massive double black holes, and a theory of how the universe became filled with light, many eons after the Big Bang:

https://www.universetoday.com/137062/another-monster-black-hole-found-milky-way/

https://www.universetoday.com/137048/universe-filled-light/

[Danik 2016]

Amazing! The swallowing black holes as a source of universal light! And the study seems to be recent. Summing it up:
"As Philip Kaaret, a professor in the UI Department of Physics and Astronomy and the lead author on the study, explained:

'The observations show the presence of very bright X-ray sources that are likely accreting black holes. It’s possible the black hole is creating winds that help the ionizing radiation from the stars escape. Thus, black holes may have helped make the universe transparent.'
And again:
“As matter falls into a black hole, it starts to spin and the rapid rotation pushes some fraction of the matter out. They’re producing these strong winds that could be opening an escape route for ultraviolet light. That could be what happened with the early galaxies.”
https://www.universetoday.com/137048/universe-filled-light/

[Dreamwoven]

Yes, its amazing how much we are starting to learn about these odd things like black holes and the Milky Way and how it is changing and evolving.

The evolution of the Milky Way, if this theory is correct, puts an extra dimension on evolution. Gives a history to what happened next.

[Danik 2016]

Yes, I read that article too. What gets me most is the imaginative power that is behind all those researches. I think that is the point that links this tread to literature. I am very glad you opened it, because I am learning a lot about the interplanetary world.

[Dreamwoven]

Yes, it is very complex out there. Fascinating, too!

[Dreamwoven]

The next post on universetoday.com follows up on the previous post. Quasars:

"Back in the 1950s, astronomers scanned the skies using radio telescopes, and found a class of bizarre objects in the distant Universe. They were very bright, and incredibly far away; hundreds of millions or even billion of light-years away. The first ones were discovered in the radio spectrum, but over time, astronomers found even more blazing in the visible spectrum.

The astronomer Hong-Yee Chiu coined the term “quasar”, which stood for quasi-stellar object. They were like stars, shining from a single point source, but they clearly weren’t stars, blazing with more radiation than an entire galaxy."

The rest of the post needs also to be read:

https://www.universetoday.com/137069/supermassive-black-holes-galaxies-came-first/

[Danik 2016]

Thanks, DW.

Here is a related article. Black holes are definitely the current "stars":

https://www.sciencedaily.com/releases/2017/09/170901135518.htm

[Dreamwoven]

sciencedaily.com looks to be a good site to follow...

[Danik 2016]

There are four or five similar astronomy sites. Here is another one:

https://phys.org/space-news/astronomy/

[Dreamwoven]

Yes, its getting to the point where we have to choose which site(s) to follow.

[Dreamwoven]

For many years I followed this website: https://www.space.com/.

But since I stopped for a couple of months I don't follow this site. Pity...

[Danik 2016]

I usually choose the most interesting news from any of these sites. On first sight, all these sites seem to base the news on research. I mean they are not sensationalistic.

[Danik 2016]

For many years I followed this website: https://www.space.com/.

But since I stopped for a couple of months I don't follow this site. Pity...

I think you can subscribe for their newsletter again, any time you want.

[Dreamwoven]

Yes, I know. I must go back to following space.com, it really is an excellent site.

[Danik 2016]

A bit of plutonian geography. You never know when you will need it ;):

Pluto features given first official names
Date:
September 7, 2017
Source:
International Astronomical Union
Summary:
The Working Group for Planetary System Nomenclature of the International Astronomical Union has officially approved the naming of 14 features on the surface of Pluto. These are the first geological features on the planet to be named following the close flyby by the New Horizons spacecraft in July 2015.

https://www.sciencedaily.com/releases/2017/09/170907112411.htm

[Dreamwoven]

I rather like the planet Pluto, the outermost planet (as far as we know).

[Dreamwoven]

http://earthsky.org/space/nasa-cassini-saturn-mission-legacy

Some of the lessons of the hugely successful Saturn Mission!

[Danik 2016]

I read it. Discovering a planet with ideal life conditions seems to have become a scientific obssession.

[Danik 2016]

Uranus is a dangerous place for its moons

In a few million years, things are going to get ugly.
By Alison Klesman | Published: Monday, September 11, 2017

"Discovered in 1781, Uranus is an ice giant orbiting our Sun once every 84 Earth years. This mysterious world, which appears as just a tiny dot in most amateur telescopes, not only possesses a system of thin, faint rings, but also 27 moons (by our current count). However, at least one of those things is destined to change: new measurements indicate at least two likely collisions between four of the planet’s moons millions of years in the future."

http://www.astronomy.com/news/2017/09/uranus-colliding-moons

[Dreamwoven]

We need to be reminded how little we know about our own solar system. Uranus is largely unexplored and has many moons of its own. See http://earthsky.org/space/nasa-cassini-saturn-mission-legacy

[Dreamwoven]

The same applies to Neptune...

[Danik 2016]

I think all these planets are still mostly unexplored. The scientists have to perfectionate their tools and instruments first. A lot of expertise and money is spent on it.

[Dreamwoven]

The more I think of it, the more odd it is that there are no plans that I know of to send probes to these ice giants and their moons. Puzzling...

[Dreamwoven]

The last visit was 40 years ago with the two Voyager flybys. They are still in the sun's field of gravity but eventually will pull clear of the sun and continue outward. Voyager 1: https://en.wikipedia.org/wiki/Voyager_1
Voyager 2: https://en.wikipedia.org/wiki/Voyager_2

These both carried messages to any humans who might be out there.

[Danik 2016]

Jupiter’s aurora presents a powerful mystery

"Jupiter has the most powerful aurora in the solar system, so the team was not surprised that electric potentials play a role in their generation. What’s puzzling the researchers, Mauk said, is that despite the magnitudes of these potentials at Jupiter, they are observed only sometimes and are not the source of the most intense auroras, as they are at Earth."
https://astronomynow.com/2017/09/09/jupiters-aurora-presents-a-powerful-mystery/

[Danik 2016]

The last visit was 40 years ago with the two Voyager flybys. They are still in the sun's field of gravity but eventually will pull clear of the sun and continue outward. Voyager 1: https://en.wikipedia.org/wiki/Voyager_1
Voyager 2: https://en.wikipedia.org/wiki/Voyager_2

These both carried messages to any humans who might be out there.

Two historical missions. The "Voyagers" employed today are technically improved I suppose.

I wonder when, if ever, we will get any answers from people out there.

[Dreamwoven]

No, actually they are the two original voyagers! That is what is so amazing. 40 years later they are still in communication with NASA. Hard to believe, I know...

[Dreamwoven]

Jupiter needs another probe to follow up on all the was learned from Cassini.

https://www.universetoday.com/137158/cassini-conduct-final-flyby-titan-crashing-saturn/

The Huygens Lander was an interesting addition to all the data collected over several years by Cassini.

[Dreamwoven]

http://www.astronomy.com/news/2017/09/uranus-colliding-moons

Well we learned a bit more about Uranus and its many moons!

[Dreamwoven]

My subscription to space.com yields its first very interesting post on Cassini: https://www.space.com/38151-cassini-nears-crash-into-saturn.html

[tailor STATELY]

Jupiter moon(s) follow-ups:

NASA: Europa launch 2020... https://www.nasa.gov/feature/jpl/nasas-europa-flyby-mission-moves-into-design-phase

... https://en.wikipedia.org/wiki/Europa_Clipper

ESA: JUICE's launch 2022... https://en.wikipedia.org/wiki/Jupiter_Icy_Moons_Explorer

[Dreamwoven]

Thanks for those links, tailor, all adding extra useful information.

[Danik 2016]

This post should come after and not before the other one. It seems one has to be careful where one buys eclipse glasses.

Eclipse Aftermath Brings Lawsuit Against Amazon
By: Javier Barbuzano | September 6, 2017
Counterfeit eclipse glasses created great confusion in the days prior to the solar eclipse. Luckily few cases of eye damage have been reported.

http://www.skyandtelescope.com/astronomy-news/eclipse-glasses-aftermath-lawsuit-amazon/

[Danik 2016]

My subscription to space.com yields its first very interesting post on Cassini: https://www.space.com/38151-cassini-nears-crash-into-saturn.html

Poor Cassini!But I suppose they don´t have other uses for it. I´m curious about the images they are going to release.

[Dreamwoven]

See the links in posts 1130 and 1131 :)

[Danik 2016]

Sorry, DW. I mean the very last ones they intend to release tomorrow, 15.09.

[Dreamwoven]

Yes, that will be interesting. This, I suppose: https://www.universetoday.com/137158/cassini-conduct-final-flyby-titan-crashing-saturn/

[Danik 2016]

Yes, that´s what I mean. Tomorrow or on Saturday they will probably release the last images.

[Dreamwoven]

https://www.universetoday.com/137154/cassini-mission-will-live-forever/

It is clear that a further mission will be sent to examine the two moons, Enceladus and Europa, both of which have seas.

[Dreamwoven]

See also this: http://earthsky.org/space/video-cassini-legacy-titan-atmosphere

[Danik 2016]

Additional link about the end of the Cassini mission:

https://saturn.jpl.nasa.gov

I shouldn´t wonder if they make a science fiction movie about the mission.
One thing I am learning from these researches is that the composition and the atmosphere of the planets varies a lot from one to another.

[Dreamwoven]

Yes, the variety among "hot jupiters" is staggering. See this post: https://www.universetoday.com/137199/hubble-spots-pitch-black-planet-eats-light/

[Dreamwoven]

https://www.universetoday.com/137205/new-study-planet-9-solar-system/ presents a much more coherent theory of the way solar systems develop, based on the fact that a "planet 9" or "Planet X" exists. The first designation assumes that is a dwarf planet, an idea that has already been rejected by the new definition which re-classifies Pluto as a planet: https://en.wikipedia.org/wiki/Planet_Nine. So "planet X" is probably less controversial.

[Danik 2016]

They are messing around a lot with Pluto these days. I consider him a planet, because in astrology is a very influential one.


Here some more pictures taken by the Cassini expedition:

Farewell, Cassini: Gorgeous Final Photos Are a Fitting Send-Off for Saturn Probe

https://www.space.com/38174-cassini-saturn-farewell-photos.html

[Dreamwoven]

http://earthsky.org/space/pitch-black-exoplanet-wasp-12b This is a similar post to the one above 1142, but more detail.

[Danik 2016]

Amazing image of this dark planet!

[Dreamwoven]

Yes, it is so hot that it absorbs the light, rather than reflects it! Not that I understand why this should be...

[mal4mac]

They are messing around a lot with Pluto these days. I consider him a planet, because in astrology is a very influential one.

Astronomers couldn't care less how important astronomical objects are to astrologists.

So *within astronomy*, is Pluto still considered a planet? A quick Google search seems to indicate there are still two camps. In 2006, when it was demoted by some astronomers, the main argument was that a larger Kuiper belt object (Eris) existed. But they weren't *certain* it was larger! Now it appears that Pluto is actually larger, and is the largest object in the Kuiper belt. Another determining factor for a planet, according to some, was that it should have cleared its orbit of other objects. As there were all these Kuiper objects, Pluto hadn't done this, ergo it wasn't a planet. But, someone pointed out, with all these asteroids & comets coming near the Earth, obviously the Earth hadn't cleared its orbit, so it wasn't a planet! To me, it would seem reasonable to keep Pluto as a planet, and then define a planet as anything at least as large as Pluto. (They still reckon Eris is more massive, so *size* should be the determining factor :). But the whole problem here seems to be in finding a set of really good reasons for calling something a planet or not...)

[Dreamwoven]

I am not at all sure what the new definition of a planet is. What has been decided exactly?

[Dreamwoven]

There is clearly a lot more water in the solar system that was previously thought. I thought this piece on Mars is just another example, at least of how Mars used to be in the distant past: http://earthsky.org/space/more-evidence-of-water-on-mars

[Danik 2016]

I agree with you. I found a link to the NASA definition of planet(below).
In Astrology Pluto, the regent of Scorpio, is a planet that relates to the great changes (in people, places or situations) that irrupt from the interior. For example he is related to the earthquakes,

[Danik 2016]

These seems to be be the current situation:
"The International Astronomical Union (IAU), a worldwide organization of astronomers, took on the challenge of classifying the newly found KBO (later named Eris). In 2006, the IAU passed a resolution that defined planet and established a new category, dwarf planet. Eris, Ceres, Pluto, and two more recently discovered KBOs named Haumea and Makemake, are the dwarf planets recognized by the IAU (as of July 2013). Pluto, Eris, Haumea, and Makemake are also classified as KBOs, and Ceres retains its asteroid label. There may be another 100 dwarf planets in the solar system and hundreds more in and just outside the Kuiper Belt.

Astronomers and planetary scientists did not unanimously agree with these definitions. To some it appeared that the classification scheme was designed to limit the number of planets; to others it was incomplete and the terms unclear. Some astronomers argued that location (context) is important, especially in understanding the formation and evolution of the solar system."
https://solarsystem.nasa.gov/planets/whatisaplanet

[Dreamwoven]

I thought the IAU had changed its definition of dwarf planet by dropping the criterion of having "cleared their orbit (?)" (whatever that may mean), but it seems they have not, just widened the definition to include more "dwarf planets". Your last paragraph (above) accurately reflects the confusion around this whole question.

[Dreamwoven]

The subject is still unresolved.

See the long discussion here: https://en.wikipedia.org/wiki/IAU_definition_of_planet.

And the discussion around "clearing the neighbourhood": https://en.wikipedia.org/wiki/Clearing_the_neighbourhood.

For me this is the key issue. Has Earth "cleared its neighbourhood"? Not according to some, and I have to say I tend to agree.

[Dreamwoven]

On which see https://io9.gizmodo.com/5775229/should-earth-get-demoted-from-planet-status-just-like-pluto

[Danik 2016]

I thought the IAU had changed its definition of dwarf planet by dropping the criterion of having "cleared their orbit (?)" (whatever that may mean), but it seems they have not, just widened the definition to include more "dwarf planets". Your last paragraph (above) accurately reflects the confusion around this whole question.

Good links, DW.
That´s what´s makes current Astronomy so fascinating to me. A lot of set concepts have to be revised to explain the new discoveries.

[Danik 2016]

This discussion probably will go on for a good time. I think the reason for it is that they have much more refined ways to observe the planets. The clutter in the neighborhood wasn´t taken into account before, because it hadn´t be observed.

But one mustn´t worry. If they decide sometime in the future that the earth isn´t a planet, they will find another definition for it, I think. Even basic concepts change. See the discoveries of Galileo.

[Dreamwoven]

Good point, Danik.

This is a quite different post, abut using nanosatellites to investigate the many smaller object (asteroids) in the asteroid belt.
See this link:https://www.universetoday.com/137253/300-asteroids-explored-fleet-nanosatellites/

[Dreamwoven]

This website post looks at how it is planned to avoid collision with an asteroid, that is inevitable sooner or later:
https://www.universetoday.com/137266/scientists-urge-europe-stick-armageddon-style-asteroid-mission/

Oh, and regarding Earth having "cleared its neighbourhood" (se the previous posts on this), NASA doesn't agree.

[Danik 2016]

Good point, Danik.

This is a quite different post, abut using nanosatellites to investigate the many smaller object (asteroids) in the asteroid belt.
See this link:https://www.universetoday.com/137253/300-asteroids-explored-fleet-nanosatellites/

Just read this post. Absolutely amazing. I think one can sum up several of all these discoveries in two or three important ones:
1- The space between planets and stars is filled with smaller celestial objects or fragments, some of which might be put to scientific use.
2-Celestial bodies present very different compositions and atmospheres.

[Danik 2016]

I hope they succeed and Didi doesn´t fall on our heads. I don´t know if this huma messing around with the universe, which still is somewhat timid if you take into account its dimension, might start to influence the movement of the celestial bodies.

[Dreamwoven]

I doubt that, but you never know.

[Dreamwoven]

I thought it was remarkable that some asteroids have their own moon and their own rings! And that some are made of sold nickel and solid iron:

"The more that planetary astronomers study asteroids, they more they’re realizing just how varied and different they can be. Some, like 16 Psyche are made of solid nickel and iron, while others are made of rock. Some asteroids have been found with moons, rings, and some icy objects really blur the line between comet and asteroid. In order to truly understand their nature, it would take dozens or maybe hundreds of individual missions on the scale of Rosetta or New Horizons."

[Danik 2016]

About the constitution of our own planet:

https://www.space.com/38235-earth-elemental-makeup-how-planet-formed.html

[Dreamwoven]

The most interesting facts from this piece has to be the next exploration of Mars in 2018, to probe the planet's deep interior.

[Dreamwoven]

I subscribed to Popular Astronomy] for a year and am re-reading it again. I am impressed by the large amount of material in it. I will select particularly interesting articles from the occasional more in-depth articles. The first will be about the moons of Mars.

[Dreamwoven]

https://en.wikipedia.org/wiki/Moons_of_Mars

I don't buy the suggestion that Earth has one moon, so Mars must have two! Nor that the Gulliver's Travels just guessed the detailed information he provides about these two moons. More likely that the ancient astronomers knew from their own observations.

Phobos, Mars' larger moon, is slowly spiralling inwards towards the planet, estimated to disintegrate within the next 30-50 million years. Phobos has the inner orbit, Deimos is further out. There is a tremendous strain on Phobos. We know that our own Moon affects tides and Phobos is covered in fractures and has a large crater (Stickney Crater).

[Danik 2016]

I agree with you. As it isn´t known that writers Like Swift and Voltaire conducted any astronomical research of their own, they must needs have been influenced by the information of th period and a bit by their own imagination.
Now we know that the universe is cluttered with bigger and smaller objects, they probably are going to find a lot of asteroids between Mars and its moons.

[Dreamwoven]

In March-April 2016 Popular Astronomy(p.18) published an article on the search for extraterrestrial life. Quoting Sir Arthur C Clarke (https://en.wikipedia.org/wiki/Arthur_C._Clarke): "Two possibilities exist: either we are alone in the universe, or we are not. Both are equally terrifying".

Links to further reading:

The best link is, I think, the first one, as it poses some interesting dilemmas:
https://waitbutwhy.com/2014/05/fermi-paradox.html

The other two I include here pose the usual dilemmas:

https://www.space.com/25325-fermi-paradox.html
https://sv.wikipedia.org/wiki/Fermis_paradox

This website looks at the Search for ExtraTerrestrial Intelligence (SETI): https://seti.org

[Dreamwoven]

There are some peculiar phenomena on our doorstep, one of which was identified by the Hubble Space Telescope:
https://www.universetoday.com/137278/hubble-spots-unique-object-asteroid-belt/.

This is a binary asteroid in the main asteroid belt between Mars and Jupiter.

[Danik 2016]

In March-April 2016 Popular Astronomy(p.18) published an article on the search for extraterrestrial life. Quoting Sir Arthur C Clarke (https://en.wikipedia.org/wiki/Arthur_C._Clarke): "Two possibilities exist: either we are alone in the universe, or we are not. Both are equally terrifying".

Links to further reading:

The best link is, I think, the first one, as it poses some interesting dilemmas:
https://waitbutwhy.com/2014/05/fermi-paradox.html

The other two I include here pose the usual dilemmas:

https://www.space.com/25325-fermi-paradox.html
https://sv.wikipedia.org/wiki/Fermis_paradox

This website looks at the Search for ExtraTerrestrial Intelligence (SETI): https://seti.org
Interesting LINK;
"There’s something called The Kardashev Scale, which helps us group intelligent civilizations into three broad categories by the amount of energy they use:

A Type I Civilization has the ability to use all of the energy on their planet. We’re not quite a Type I Civilization, but we’re close (Carl Sagan created a formula for this scale which puts us at a Type 0.7 Civilization).

A Type II Civilization can harness all of the energy of their host star. Our feeble Type I brains can hardly imagine how someone would do this, but we’ve tried our best, imagining things like a Dyson Sphere.
A Type III Civilization blows the other two away, accessing power comparable to that of the entire Milky Way galaxy.
...
That said, given that my normal outlook is that humanity is a lonely orphan on a tiny rock in the middle of a desolate universe, the humbling fact that we’re probably not as smart as we think we are, and the possibility that a lot of what we’re sure about might be wrong, sounds wonderful. It opens the door just a crack that maybe, just maybe, there might be more to the story than we realize."

https://waitbutwhy.com/2014/05/fermi-paradox.html

[Danik 2016]

There are some peculiar phenomena on our doorstep, one of which was identified by the Hubble Space Telescope:
https://www.universetoday.com/137278/hubble-spots-unique-object-asteroid-belt/.

This is a binary asteroid in the main asteroid belt between Mars and Jupiter.

Some of it´s unusual features:
"Using the Hubble telescope, the team first observed 288P in September 2016, when it was making its closest approach to Earth. The images they took revealed that this object was not a single asteroid, but two asteroids of similar size and mass that orbit each other at a distance of about 100 km. Beyond that, the team also noted some ongoing activity in the binary system that was unexpected.

As Jessica Agarwal explained in a Hubble press statement, this makes 288P the first known binary asteroid that is also classified as a main-belt comet. “We detected strong indications of the sublimation of water ice due to the increased solar heating – similar to how the tail of a comet is created,” she said. In addition to being a pleasant surprise, these findings are also highly significant when it comes to the study of the Solar System."

[Dreamwoven]

Thanks, Danik, those were two interesting responses.

[Danik 2016]

"Highest-energy cosmic rays have extragalactic origin

A 50-year-old debate has at last been settled: the highest-energy cosmic rays do not originate in our own galaxy but in galaxies located tens or even hundreds of millions of light-years away."

https://astronomynow.com/2017/09/26/highest-energy-cosmic-rays-have-extragalactic-origin/

[Dreamwoven]

Your astronomy Now post is intriguing. But can we "read" what the high energy rays are communicating, if anything at all? I must subscribe to Astronomy Now! (Done).

[Danik 2016]

Not yet, if they are comunicating anything at all. What also called my atention is that the observatory, in this case, is Argentinian.

"By comparing the arrival times of particles at the different detectors it is possible to determine where the cosmic ray particle that produced the air shower came from.

This discovery clearly indicates an extragalactic origin for these cosmic rays, since there is a probability of only one in five million that the pattern observed in the sky is due to chance. However, the study has not yet succeeded in locating the sources precisely. This is because the region where cosmic rays are brightest covers a large part of the sky, where the number of galaxies is relatively high. In addition, our galaxy’s magnetic field deflects the paths of these charged particles, making it more difficult to locate their sources."

[Dreamwoven]

The last issue of Popular Astronomy that I have (Jan-Feb 2017) has a lead article on Proxima b, asking if life could exist there. Proxima Centauri is the closest stellar neighbour to our Sun, and is a red dwarf star. Proxima b is an inner planet so may be made of rock and is in the so-called "habitable zone" of its star. we do not know whether Proxima b has water on its surface, nor if it has the ability to sustain an atmosphere. But the new Spitzer Space Telescope that came into service in 2016 - https://en.wikipedia.org/wiki/Spitzer_Space_Telescope - should be able to tell us more.

[Danik 2016]

Two links about the Mars colonization project:

https://www.space.com/38315-spacex-mars-colonization-architecture-bfr-images.html

Elon Musk Wants Giant SpaceX Spaceship to Fly People to Mars by 2024

"SpaceX aims to launch its first cargo mission to Mars in 2022 and send people toward the Red Planet just two years after that."

https://www.space.com/38313-elon-musk-spacex-fly-people-to-mars-2024.html

[Dreamwoven]

Deep Space Gateway: https://www.universetoday.com/137320/russia-says-theyll-pitching-deep-space-gateway/

There is a new enthusiasm for this internationally, led by the USA and Russia (NASA and Roscosmos jointly) and separately by China and India. The idea is to provide for a deep space gateway from which to explore the solar system.

[Danik 2016]

I suppose it will have to be a joint venture between countries, because of the demanded technology and the expenses that arise from such a project and I think that is positive. Also there is the political aspect to consider.

[Dreamwoven]

I forgot to add Japan to the countries interested in the moon as a potential base. All have satellites going round the moon. Yes, the collaboration is necessary and, as you say, there is the political aspect to consider.

The country with the most advanced plans is clearly China. The new China mission - Chang'e3 - planned is is to have a rover/lander on board. Russia has invested most in the International Space Station and is picking sites for a moon base. So the political angle in the NASA-Roscosmos alliance is necessary if they want to be first to locate a site and begin the moon-base. This will in any case be permanently staffed by astronauts, once built. A new space-race is in then offing, though that is probably a few years away.

[Danik 2016]

Yes. Once it startes it will be a race won by the powerfull countries with the most financial and technological resources. The age of the great discoveries will be reedited in its spacial version.

Meanwhile in Brazil:

"Cuts imperil Brazil’s stake in astronomy observatories
This is a very serious situation,” said Bruno Castilho, director of the National Astrophysics Laboratory in Itajubá, Brazil. His budget also was halved this year. Current reserves don’t even cover water and electricity bills, he says, let alone Brazil’s participation in the Gemini Observatory—twin optical and infrared telescopes in Chile and Hawaii—and the Southern Astrophysical Research Telescope in Chile. If Castilho can’t find at least another 4 million reais ($1.25 million) by the end of the year, he says, Brazilian astronomers will lose access to those facilities. The prognosis is grim, he says: “We don’t have anywhere else to cut.”

http://www.sciencemag.org/news/2017/07/cuts-imperil-brazil-s-
stake-astronomy-observatories

:bawling::bawling::bawling:

[Dreamwoven]

I forgot to add Japan to the countries interested in the moon as a potential base. All have satellites going round the moon. Yes, the collaboration is necessary and, as you say, there is the political aspect to consider.

The country with the most advanced plans is clearly China. The new China mission - Chang'e3 - planned is is to have a rover/lander on board. Russia has invested most in the International Space Station and is picking sites for a moon base. So the political angle in the NASA-Roscosmos alliance is necessary if they want to be first to locate a site and begin the moon-base. This will in any case be permanently staffed by astronauts, once built. A new space-race is in then offing, though that is probably a few years away.

[Dreamwoven]

I've been struggling to understand the dark energy debate. Gravitational waves (https://en.wikipedia.org/wiki/Gravitational_wave) and Black holes (https://en.wikipedia.org/wiki/Black_hole) are clearly connected. Black holes form as a result. As I see it, this means that black holes function as a sort of rubbish bin that can dispose of matter (like stars at the end of their lives when they become red dwarf stars?).

I'm not at home at this level of debate (though we all probably feel the same way) but perhaps we will learn more as time goes on.

See also https://astronomynow.com/2017/09/18/new-supernova-analysis-reframes-dark-energy-debate/.

[Dreamwoven]

See also https://www.universetoday.com/137319/ligo-virgo-observatories-detect-black-holes-colliding/

[Danik 2016]

=Dreamwoven;1343353]I've been struggling to understand the dark energy debate. Gravitational waves (https://en.wikipedia.org/wiki/Gravitational_wave) and Black holes (https://en.wikipedia.org/wiki/Black_hole) are clearly connected. Black holes form as a result. As I see it, this means that black holes function as a sort of rubbish bin that can dispose of matter (like stars at the end of their lives when they become red dwarf stars?).

Interesting links, DW.


I'm not at home at this level of debate (though we all probably feel the same way) but perhaps we will learn more as time goes on.

Neither are the astronomers themselves it seems:

"Dark energy is usually assumed to form roughly 70% of the present material content of the universe. However, this mysterious quantity is essentially a place-holder for unknown physics."

https://astronomynow.com/2017/09/18/new-supernova-analysis-reframes-dark-energy-debate/

[Danik 2016]

"LIGO AND VIRGO OBSERVATORIES DETECT BLACK HOLES COLLIDING

'With this first joint detection by the Advanced LIGO and Virgo detectors, we have taken one step further into the gravitational-wave cosmos,' he said. 'Virgo brings a powerful new capability to detect and better locate gravitational-wave sources, one that will undoubtedly lead to exciting and unanticipated results in the future.'

The study of gravitational waves is a testament to the growing capability of the world’s science teams and the science of interferometry. For decades, the existence of gravitational waves was merely a theory; and by the turn of the century, all attempts to detect them had yielded nothing. But in just the past eighteen months, multiple detections have been made, and dozens more are expected in the coming years.

What’s more, thanks to the new global network and the improved instruments and methods, these events are sure to tell us volumes about our Universe and the physics that govern it."

https://www.universetoday.com/137319/ligo-virgo-observatories-detect-black-holes-colliding/

[Dreamwoven]

Yes, indeed!

[Dreamwoven]

Plans for the advance base camp for Mars: https://www.universetoday.com/137361/lockheed-martin-unveils-details-proposed-base-camp-mars/

[Danik 2016]

I understand the hurry in getting astronauts landed on Mars, but I think they have to be very carefull about the atmospheric and subsistence conditions. If I were an astronaut I certainly wouldn´t be satisfied just with iced water. I would want at least a fast food facility.

[Dreamwoven]

I think the idea is to set up an advance camp on the moon, so all supplies would be there for further shipment to Mars. I can't imagine that they would have to live on iced water.

This is a shot from the ISS of the moon and planets seen in the sky: http://earthsky.org/space/video-iss-moon-planets-rising-sep-2017

[Danik 2016]

Lovely rising!

And look who has won the Nobel prize in physics:

Nobel prize in physics awarded for discovery of gravitational waves
£825,000 prize awarded to Rainer Weiss, Barry Barish and Kip Thorne for their work on Ligo experiment which was able to detect ripples in the fabric of spacetime

https://www.theguardian.com/science/2017/oct/03/nobel-prize-physics-discovery-gravitational-waves-ligo

[Dreamwoven]

Yes, but they released the news to Nobel just before the meeting. There is a lot of tactics involved. Like choosing your team of people and if possible having Oxbridge academics on the team.

But all that aside its nice to see astronomy winning the Nobel Prize...

[Danik 2016]

I quite agree that the choices for the Nobel prize are anything but neutral and unbiased.
But, anyway, the inclusion of astronomers is significant.

[Dreamwoven]

Popular Astronomy Nov/Dec 2016, "Citizen Science" p. 15

Alice Sheppard has been involved with citizen science for 9 years, first running the Galaxy Zoo discussions (https://www.galaxyzoo.org) now working at University College, London) Extreme Citizen Science Department.

Jenny McCormick (Farm Cove Observatory) http://www.farmcoveobs.co.nz has a 14-inch telescope and uses it to carry out microlensing: https://en.wikipedia.org/wiki/Gravitational_microlensing

Sadly, living in a forested part of Sweden the amount of clear sky I can see from our house is very limited. I do have 7x50 mm binoculars but the best I can do is to observe the moon when it is in the east.

[Danik 2016]

It is still better, DW, than living in a metropolis full of sky scraper where you forget there is a sky with moon and stars (and a lot of asteroids) in it.

[Dreamwoven]

I would conclude that citizen science is making a major contribution to knowledge about space and the many worlds to be discovered in it. Perhaps this is just a phase of space exploration, but it is notable how much citizen science is being conducted out there. For further information see https://en.wikipedia.org/wiki/Planet_Hunters.

[Danik 2016]

Interesting link, DW.

About planet nine again:
"The super-Earth that came home for dinner
Date:
October 4, 2017
Source:
NASA/Jet Propulsion Laboratory
Summary:
It might be lingering bashfully on the icy outer edges of our solar system, hiding in the dark, but subtly pulling strings behind the scenes: stretching out the orbits of distant bodies, perhaps even tilting the entire solar system to one side. It is a possible "Planet Nine" -- a world perhaps 10 times the mass of Earth and 20 times farther from the sun than Neptune."

https://www.sciencedaily.com/releases/2017/10/171004144511.htm

[Dreamwoven]

Planet 9 is an interesting discovery. Look forward to its confirmation.

[Dreamwoven]

Space Junk: (a case of citizen science), Alice Sheppard published a piece in Popular Astronomy (Jan-Feb 2017 p.17).

See also: https://www.nasa.gov/mission_pages/station/news/orbital_debris.html
and
https://en.wikipedia.org/wiki/Space_debris

[Dreamwoven]

In Popular Astronomy p.19, China is clearly investing in Moon exploration. I December 2013 the Chang'e 3 mission delivered their Moon Rover, Jade Rabbit, to the Moon. Designed to last 3 months it has kept up exploring and lasted for more than 2 years. Returning to the Chang'e 3 lander each night helped. Jade Rabbit is equipped with a "small robotic telescope". Chang'e 4 will be launched in 2018 intending to explores the far side of the Moon. The Moon is tidally-locked and so this will be a new and interesting mission.

NASA has decided to make the next giant leap and will explore the moon. See https://www.space.com/38379-united-states-return-moon-mike-pence.html.

[Dreamwoven]

It is Popular Astronomy's comprehensive coverage that is it strong advantage over other websites, like the Swedish version Populär Astronomi which comes out every 3 months and is far less thorough in its coverage of news.

[Dreamwoven]

Another report in Popular Astronomy (Nov-Dec 2016 p. 5) is on sampling mission by NASA to the asteroid Bennu. It was launched on 8 September 2016, and is expected to take 2 years to reach Bennu. It will change its course as a result of the Yarkovsky Effect: https://en.wikipedia.org/wiki/Yarkovsky_effect resulting from heat from the Sun on the asteroid. This might result in the asteroid hitting Earth (less than 1% chance in the 23rd century). It should reach Bennu by 2018, taking samples over an 18 to 24 month period. It is unclear whether the sampling will be done and analysed at Goddard or taken by another mission.

You can read more about it at this link:

https://www.nasa.gov/content/goddard/bennus-journey

[Dreamwoven]

Another report in Popular Astronomy is on sampling mission by NASA to the asteroid Bennu. It was launched on 8 September 2016, and is expected to take 2 years to reach Bennu. It will change its course as a result of the Yarkovsky Effect: https://en.wikipedia.org/wiki/Yarkovsky_effect resulting from heat from the Sun on the asteroid. This might result in the asteroid hitting Earth (less than 1% chance in the 23rd century). It should reach Bennu by 2018, taking samples over an 18 to 24 month period. It is unclear whether the sampling will be done and analysed at Goddard or taken by another mission.

You can read more about it at this link:

https://www.nasa.gov/content/goddard/bennus-journey

[Danik 2016]

In Popular Astronomy p.19, China is clearly investing in Moon exploration. I December 2013 the Chang'e 3 mission delivered their Moon Rover, Jade Rabbit, to the Moon. Designed to last 3 months it has kept up exploring and lasted for more than 2 years. Returning to the Chang'e 3 lander each night helped. Jade Rabbit is equipped with a "small robotic telescope". Chang'e 4 will be launched in 2018 intending to explores the far side of the Moon. The Moon is tidally-locked and so this will be a new and interesting mission.

NASA has decided to make the next giant leap and will explore the moon. See https://www.space.com/38379-united-states-return-moon-mike-pence.html.

Lol! Jade Rabbit is a curious name for a mission. I hope they leave real rabbits out of it. I think that one reason why they want to return to the moon is because men on the moon makes for headlines. And as we noticed several time, there seems to be quite an human obssession to dominate other parts of the universe besides the earth.

[Danik 2016]

Another report in Popular Astronomy is on sampling mission by NASA to the asteroid Bennu. It was launched on 8 September 2016, and is expected to take 2 years to reach Bennu. It will change its course as a result of the Yarkovsky Effect: https://en.wikipedia.org/wiki/Yarkovsky_effect resulting from heat from the Sun on the asteroid. This might result in the asteroid hitting Earth (less than 1% chance in the 23rd century). It should reach Bennu by 2018, taking samples over an 18 to 24 month period. It is unclear whether the sampling will be done and analysed at Goddard or taken by another mission.

You can read more about it at this link:

https://www.nasa.gov/content/goddard/bennus-journey

An amazing mission, but I hope it doesn´t hit the earth. Now that we know that the sky between planets isn´t empty, but full of stellar debris, the fear of colisions seems to have increased.
Just now opening PC on a rainy Saturday morning at 11 AM, probably four or five hours after European time.

[Danik 2016]

Lol!There they come with their ice cubes again. I wonder when we will have the first spacial manufactured burger.
More on:
A cheaper way to stock up in space
A NASA mission is sponsoring undergraduate research to test space-based manufacturing.

Access the corrected link at #1210.

[Dreamwoven]

I share those doubts about setting up a community on Mars, I think many people jumped at the idea without thinking it through. That includes Musk. A luna base is much more practical.

The link in the previous post doesn't work. It must be a regional thing...

[Dreamwoven]

This is from the notes I still get from my subscription to the Society for Popular Astronomy.

HIDDEN SITES FOR HUMAN HABITATS ON MOON AND MARS
Europlanet Media Centre

Lava tubes --underground caves created by volcanic activity -- could
provide protected habitats large enough to house streets on Mars or
even towns on the Moon, according to research presented at the
European Planetary Science Congress (EPSC) 2017 in Riga. A further
study shows how the next generation of lunar orbiters will be able to
use radar to locate such structures under the Moon's surface. Lava
tubes can form in two ways. 'Overcrusted' tubes form when low-
viscosity lava flows fairly close to the surface, developing a hard
crust that thickens to create a roof above the moving lava stream.
When the eruptions end, the conduit is drained, leaving a tunnel a few
metres beneath the surface. 'Inflated' tubes are complex and deep
structures that form when lava is injected into existing fissures
between layers of rock or cavities from previous flows. The lava
expands and leaves a huge network of connected galleries as it forces
its way to the surface. Lava tubes are found in many volcanic areas
on Earth, including Lanzarote, Hawaii, Iceland, North Queensland in
Australia, Sicily, and the Galapagos islands. Underground networks of
tubes can span up to 65 kilometres. Space missions have also observed
chains of collapsed pits and 'skylights' on the Moon and Mars that
have been interpreted as evidence of lava tubes. Recently the NASA
GRAIL mission provided detailed gravity data for the Moon that
suggested the presence of enormous sub-surface voids related to lava
tubes below the lunar 'maria', plains of basalt formed in volcanic
eruptions early in the Moon's history. Scientists have also presented
a concept for a radar system specifically designed to detect lava
tubes on the Moon from orbit. The radar will probe beneath the lunar
surface with low-frequency electromagnetic waves and measure the
reflected signals. Such a radar instrument could determine accurately
the physical composition, size and shape of the caves and obtain a
global map of their locations. The studies show that a multi-
frequency sounding system is the best option for detecting lava tubes
of very different dimensions. The simulations show that lava tubes
have unique electromagnetic signatures, which can be detected from
orbit irrespective of their orientation with respect to the radar
movement direction. Therefore, an orbiter carrying such an instrument
could make a crucial step towards finding safe habitats on the Moon
for human colonisation.

[Danik 2016]

Well, at this state of development, I wouldn´t envy the first colonizators. But many human discoveries started as human obsessions I think.


Sorry, DW. I corrected the link. It should open now.

http://astronomy.com/news/2017/10/spaceice-fabrication-up-in-space

[Dreamwoven]

Dagens Nyheter has a page-long report on the 60th Anniversary of the launching of Sputnik by the Soviet Union. This can be said to be the birth of the Space Age. Followed by the first Soviet astronaut in space, Yuri Gagarin, and the development of NASA that we see today.

[Dreamwoven]

Separately, I thought the idea of tunnels on planets and moons was very interesting (see post #1209 above), as it would be a neat development of habitations in outer space environments.

[Danik 2016]

Separately, I thought the idea of tunnels on planets and moons was very interesting (see post #1209 above), as it would be a neat development of habitations in outer space environments.

Yes, I read it, but it doesn´t sound very cosy to me. Something like Space Cavern Men 21. C.

[Dreamwoven]

Heh, yes, it may well turn out that way.

[Dreamwoven]

This is from the notes I still get from my subscription to the Society for Popular Astronomy (which is no longer active).

This report suggests there is surface ice on Mercury, if confirmed this would be astonishing.

MERCURY'S POLES ICIER THAN WAS THOUGHT
Brown University

The scorching-hot surface of Mercury may seem an unlikely place to
find ice, but research over the past 30 years has indicated that water
is frozen there, hidden away on crater floors that are permanently
shadowed from the Sun's blistering rays. Now, a new study suggests
that there could be much more ice on Mercury's surface than previously
thought. The study adds three new members to the list of craters
near Mercury's north pole that appear to harbour large surface ice
deposits. But in addition to those large deposits, the research also
shows evidence that smaller-scale deposits are scattered around
Mercury's north pole, both inside craters and in permanently shadowed
areas between craters. Those deposits may be small, but they could
add up to a lot of previously-unaccounted-for ice. The idea that
Mercury might have frozen water emerged in the 1990s, when Earth-based
radars detected highly reflective regions inside several craters near
Mercury's poles. The planet's axis does not have much tilt, so its
poles get little direct sunlight, and the floors of some craters get
no direct sunlight at all. Without an atmosphere to hold in any heat
from surrounding surfaces, temperatures in those eternal shadows have
been calculated to be plenty low enough for water ice to be stable.
That raised the possibility that the 'radar-bright' regions could be
ice. That idea got a boost after NASA's MESSENGER probe entered an
orbit around Mercury in 2011. The spacecraft detected neutron signals
from the planet's north pole that were consistent with water ice.

[Dreamwoven]

This is yet another probe that I knew nothing about: NASA's Messenger orbiting the planet Mercury.

[Dreamwoven]

I did indeed know about this, just not got round to searching for the internet link:

https://astronomynow.com/2017/10/05/jwst-launch-slips-to-early-2019/

[Danik 2016]

This is from the notes I still get from my subscription to the Society for Popular Astronomy (which is no longer active).

This report suggests there is surface ice on Mercury, if confirmed this would be astonishing.

MERCURY'S POLES ICIER THAN WAS THOUGHT
Brown University

The scorching-hot surface of Mercury may seem an unlikely place to
find ice, but research over the past 30 years has indicated that water
is frozen there, hidden away on crater floors that are permanently
shadowed from the Sun's blistering rays. Now, a new study suggests
that there could be much more ice on Mercury's surface than previously
thought. The study adds three new members to the list of craters
near Mercury's north pole that appear to harbour large surface ice
deposits. But in addition to those large deposits, the research also
shows evidence that smaller-scale deposits are scattered around
Mercury's north pole, both inside craters and in permanently shadowed
areas between craters. Those deposits may be small, but they could
add up to a lot of previously-unaccounted-for ice. The idea that
Mercury might have frozen water emerged in the 1990s, when Earth-based
radars detected highly reflective regions inside several craters near
Mercury's poles. The planet's axis does not have much tilt, so its
poles get little direct sunlight, and the floors of some craters get
no direct sunlight at all. Without an atmosphere to hold in any heat
from surrounding surfaces, temperatures in those eternal shadows have
been calculated to be plenty low enough for water ice to be stable.
That raised the possibility that the 'radar-bright' regions could be
ice. That idea got a boost after NASA's MESSENGER probe entered an
orbit around Mercury in 2011. The spacecraft detected neutron signals
from the planet's north pole that were consistent with water ice.

These recent finds suggests that there probably exist other water freezing physical laws, than the ones one learns at school.

[Danik 2016]

I did indeed know about this, just not got round to searching for the internet link:

https://astronomynow.com/2017/10/05/jwst-launch-slips-to-early-2019/

With so much involved I think they are right in taking the necessary time.

By the way, French Guiana is one of our northern neighbors:

https://www.lonelyplanet.com/maps/south-america/french-guiana/

[Dreamwoven]

These recent finds suggests that there probably exist other water freezing physical laws, than the ones one learns at school.

Maybe!

[Dreamwoven]

The eternal question...
https://www.space.com/37988-did-life-emerge-from-physical-laws.html

[Danik 2016]

A very interesting theory. Maybe England is on the way to something there.

"Self-organization in physical systems
When energy is applied to a system, the laws of physics dictate how that energy dissipates. If an external heat source is applied to that system, it will dissipate and reach thermal equilibrium with its surroundings, like a cooling cup of coffee left on a desk. Entropy, or the amount of disorder in the system, will increase as heat dissipates. But some physical systems may be sufficiently out of equilibrium that they "self-organize" to make best use of an external energy source, triggering interesting self-sustaining chemical reactions that prevent the system from reaching thermodynamic equilibrium and thus maintaining an out-of-equilibrium state, England speculates. (It's as if that cup of coffee spontaneously produces a chemical reaction that sustains a hotspot in the center of the fluid, preventing the coffee from cooling to an equilibrium state.) He calls this situation "dissipation-driven adaptation" and this mechanism is what drives life-like qualities in England’s otherwise lifeless physical system.

A key life-like behavior is self-replication, or (from a biological viewpoint) reproduction. This is the basis for all life: It starts simple, replicates, becomes more complex and replicates again. It just so happens that self-replication is also a very efficient way of dissipating heat and increasing entropy in that system."

[Dreamwoven]

I've lost the drift of this logic, sorry...

[YesNo]

One of the features of self-organization is the ability to be goal directed. That system has goals and purposes. It makes choices. Machines don't do that.

To say that life may be a "fluke" is an admission of defeat, so England is at least trying to find an explanation which is what science should be doing. Even if the explanation comes down to some conscious choice at some level, that is a better explanation than to say it happened by chance. However, I don't think England wants there to be a conscious choice at all involved.

[Danik 2016]

I've lost the drift of this logic, sorry...

No matter, I only cited from the article.

[Danik 2016]

"New research helps solve galactic murders

Why do galaxies stop making stars?

The stars and galaxies we see in the night sky appear unchanging, but they all undergo dynamic processes, evolving throughout their lifetimes. While scientists don’t know exactly what mixture of cosmic events leads to the termination of star formation across galaxies, they have found several key players.

A leading cause of galaxy death is ram-pressure stripping. Drawn in by gravitation attraction, galaxies tend to group together in clusters. The space between galaxies in these clusters is filled with hot gas, and as the galaxies move through the cluster, the gas acts as a headwind. When the wind is strong enough, it can remove loose gas within the galaxy itself — gas that would typically be used to create new stars."

http://www.astronomy.com/news/2017/10/new-research-helps-solve-galactic-murders

[Dreamwoven]

The birth and death of stars is especially interesting.

[Dreamwoven]

Notes from the Society for Popular Astronomy:

NANOSAT FLEET PROPOSED TO VISIT 300 ASTEROIDS
European Planetary Science Congress

A fleet of tiny spacecraft could visit over 300 asteroids in just
over three years, according to a mission study led by the Finnish
Meteorological Institute. The Asteroid Touring Nanosat Fleet concept
comprises 50 spacecraft propelled by innovative electric solar wind
sails (E-sails) and equipped with instruments to take images and
collect spectroscopic data on the composition of the asteroids. Each
nanosat would visit six or seven asteroids before returning to Earth
to deliver the data. In the mission scenario, the nanosats fly by
their target asteroids at a range of around 1000 kilometres. Each
nanosat carries a 4-centimetre telescope capable of imaging the
surface of asteroids with a resolution of 100 metres or better. An
infrared spectrometer analyses spectral signatures in light reflected
or emitted by the asteroid to determine its mineralogy. The instru-
ments can be pointed at the target by the use of two internal reaction
wheels inside the nanosats. E-sails make use of the solar wind -- a
stream of electrically charged particles emitted from the Sun -- to
generate efficient propulsion without the need for any propellent.
Thrust is generated by the slow rotation of a tether, attached at one
end to a main spacecraft carrying an electron emitter and a high-
voltage source and at the other to a small remote unit. The spinning
tether completes a rotation in about 50 minutes, tracing out a broad,
shallow cone around a centre of mass close to the main spacecraft.
By altering its orientation in relation to the solar wind, the nanosat
can change thrust and direction

[Danik 2016]

I only wonder what all these mega space projects are going to cost.

[Dreamwoven]

One good reason for co-operation, though I notice that the idea of collaborating with Russia has been dropped. I guess Trump has taken too much flack for that idea, which is a real pity.

[Dreamwoven]

Notes for Society for Popular Astronomy:

Another visitor from the Oort Cloud:

FARTHEST ACTIVE INBOUND COMET YET SEEN
NASA

The Hubble space telescope has photographed the most distant active
inbound comet ever seen, currently beyond the orbit of Saturn.
Slightly warmed by the remote Sun, it has already begun to develop an
80,000-mile-wide coma, enveloping a tiny, solid nucleus of frozen gas
and dust. The observations represent the earliest signs of activity
ever seen from a comet entering the Solar System's planetary zone for
the first time. The comet, called C/2017 K2 (PANSTARRS) or 'K2', has
been travelling for millions of years from its home in the frigid
outer reaches of the Solar System, where the temperature is about
minus 262 degrees Centigrade. The comet's orbit indicates that it
came from the Oort Cloud, a spherical region almost a light-year in
diameter and thought to contain hundreds of billions of comets.
Comets are the icy leftovers from the formation of the Solar System
4.6 billion years ago and therefore pristine in icy composition.
The Hubble observations of K2's coma suggest that sunlight is heating
frozen volatile gases -- such as oxygen, nitrogen, carbon dioxide, and
carbon monoxide -- that coat the comet's frigid surface. Those icy
volatiles lift off from the comet and release dust, forming the coma.
Past studies of the composition of comets near the Sun have revealed
the same mixture of volatile ices. The volatiles are spread all
through K2, and in the beginning, billions of years ago, they were
probably all through every comet presently in the Oort Cloud. But the
volatiles on the surface are the ones that absorb the heat from the
Sun, so, in a sense, the comet is shedding its outer skin. Most
comets are discovered much closer to the Sun, near Jupiter's orbit, so
by the time we see them, the surface volatiles have already been baked
off. That is why astronomers think that K2 is the most primitive
comet ever seen.

K2 was discovered in 2017 May by the Panoramic Survey Telescope and
Rapid Response System (Pan-STARRS) in Hawaii, a survey project of
NASA's Near-Earth Object Observations Program. Hubble revealed the
extent of the coma and also helped to estimate the size of the nucleus
-- less than 12 miles across -- though the tenuous coma is 10 Earth
diameters across. That vast coma must have formed when the comet was
even further away from the Sun. Digging through archival images,
astronomers uncovered views of K2 and its fuzzy coma taken in 2013 by
the Canada-France-Hawaii Telescope (CFHT) in Hawaii. But the object
was then so faint that no one noticed it. It is likely that the comet
has been continuously active for at least four years. In the CFHT
data, K2 had a coma already, when it was at 2 billion miles from the
Sun, between the orbits of Uranus and Neptune. As it approaches the
Sun, it is getting warmer and warmer, and the activity is ramping up.
But curiously, the Hubble images do not show any tail flowing from K2.
The absence of such a feature indicates that the particles lifting off
the comet are too large for radiation pressure from the Sun to sweep
them back into a tail. Astronomers will have plenty of time to
conduct detailed studies of K2. For the next five years, the comet
will continue its journey into the inner Solar System before it
reaches its closest approach to the Sun in 2022 just beyond Mars'
orbit. The James Webb space telescope, an infrared observatory
scheduled to be launched in 2018, could measure the heat from the
nucleus, which would give astronomers a more accurate estimate of its
size.

[Danik 2016]

One good reason for co-operation, though I notice that the idea of collaborating with Russia has been dropped. I guess Trump has taken too much flack for that idea, which is a real pity.

Has this program been dropped?

https://www.theverge.com/2017/9/28/16378056/us-and-russia-agree-to-research-future-lunar-space-station

[Danik 2016]

Notes for Society for Popular Astronomy:

Another visitor from the Oort Cloud:

FARTHEST ACTIVE INBOUND COMET YET SEEN
NASA

The Hubble space telescope has photographed the most distant active
inbound comet ever seen, currently beyond the orbit of Saturn.
Slightly warmed by the remote Sun, it has already begun to develop an
80,000-mile-wide coma, enveloping a tiny, solid nucleus of frozen gas
and dust. The observations represent the earliest signs of activity
ever seen from a comet entering the Solar System's planetary zone for
the first time. The comet, called C/2017 K2 (PANSTARRS) or 'K2', has
been travelling for millions of years from its home in the frigid
outer reaches of the Solar System, where the temperature is about
minus 262 degrees Centigrade. The comet's orbit indicates that it
came from the Oort Cloud, a spherical region almost a light-year in
diameter and thought to contain hundreds of billions of comets.
Comets are the icy leftovers from the formation of the Solar System
4.6 billion years ago and therefore pristine in icy composition.
The Hubble observations of K2's coma suggest that sunlight is heating
frozen volatile gases -- such as oxygen, nitrogen, carbon dioxide, and
carbon monoxide -- that coat the comet's frigid surface. Those icy
volatiles lift off from the comet and release dust, forming the coma.
Past studies of the composition of comets near the Sun have revealed
the same mixture of volatile ices. The volatiles are spread all
through K2, and in the beginning, billions of years ago, they were
probably all through every comet presently in the Oort Cloud. But the
volatiles on the surface are the ones that absorb the heat from the
Sun, so, in a sense, the comet is shedding its outer skin. Most
comets are discovered much closer to the Sun, near Jupiter's orbit, so
by the time we see them, the surface volatiles have already been baked
off. That is why astronomers think that K2 is the most primitive
comet ever seen.

K2 was discovered in 2017 May by the Panoramic Survey Telescope and
Rapid Response System (Pan-STARRS) in Hawaii, a survey project of
NASA's Near-Earth Object Observations Program. Hubble revealed the
extent of the coma and also helped to estimate the size of the nucleus
-- less than 12 miles across -- though the tenuous coma is 10 Earth
diameters across. That vast coma must have formed when the comet was
even further away from the Sun. Digging through archival images,
astronomers uncovered views of K2 and its fuzzy coma taken in 2013 by
the Canada-France-Hawaii Telescope (CFHT) in Hawaii. But the object
was then so faint that no one noticed it. It is likely that the comet
has been continuously active for at least four years. In the CFHT
data, K2 had a coma already, when it was at 2 billion miles from the
Sun, between the orbits of Uranus and Neptune. As it approaches the
Sun, it is getting warmer and warmer, and the activity is ramping up.
But curiously, the Hubble images do not show any tail flowing from K2.
The absence of such a feature indicates that the particles lifting off
the comet are too large for radiation pressure from the Sun to sweep
them back into a tail. Astronomers will have plenty of time to
conduct detailed studies of K2. For the next five years, the comet
will continue its journey into the inner Solar System before it
reaches its closest approach to the Sun in 2022 just beyond Mars'
orbit. The James Webb space telescope, an infrared observatory
scheduled to be launched in 2018, could measure the heat from the
nucleus, which would give astronomers a more accurate estimate of its
size.

I´ve to go out now. Will be back later to the thread.

[Dreamwoven]

Has this program been dropped?

https://www.theverge.com/2017/9/28/16378056/us-and-russia-agree-to-research-future-lunar-space-station

No, but there is now no mention of co-operation with Russia. A great shame.

[Dreamwoven]

https://www.space.com/38432-dwarf-planet-haumea-has-rings.html

This is related to the plans to send several small probes to the Kuiper Belt to study a range of curious objects there.

[Dreamwoven]

http://earthsky.org/space/direct-distance-measurement-milky-way-far-side

Don't fully understand this, I just get the gist. A sort of mirror effect?

[Dreamwoven]

This is one example of how odd the Kuiper Belt is: a dwarf planet with rings: https://www.space.com/38432-dwarf-planet-haumea-has-rings.html

[Danik 2016]

No, but there is now no mention of co-operation with Russia. A great shame.

I agree, but that may still change. The moment isn´t favorable for cooperative projects between both countries.

[Danik 2016]

http://earthsky.org/space/direct-distance-measurement-milky-way-far-side

Don't fully understand this, I just get the gist. A sort of mirror effect?
The only thing I understood is that they have invented a new form of measurement of spacial distances.

[Dreamwoven]

Yes, that is about my understanding, too.

[YesNo]

As I understood the article, by using the VLBA which is a large array of radio telescopes they can now make more accurate measurements of the stars in the galaxy. If they compare two of these measurements for a particular star in the galaxy taken six months apart they can use "parallax" to find the distance between us and that object and get accurate distance measurements now up to 66,000 light years. Parallax is an old technique of measuring distance, but it has become more accurate because of the current accuracy of the individual VLBA measurements.

The mirror idea, I think, is that if we map enough of these distances we can construct the shape of the Milky Way as if we were outside the Milky Way and looking on it face on, like in a mirror.

[Danik 2016]

Thanks, Yes/No, I was hoping that you might trow a light on this parallax method.

[YesNo]

I don't know how parallax is actually done, but the general concept is the same as having two eyes to help us intuit distance. If you look at an object with one eye shut you will see a slightly different background than if you shut the other eye. Comparing these two views gives an estimate of the distance of an object from us. The two "eyes" in this case are the two measurements taken six months apart when the Earth is on opposite sites of the Sun. Apparently they can now take such accurate measurements using that large array at each of these two positions of the Earth that they can see differences in the backgrounds allowing them to measure distances up to 66,000 light years.

There are two ways to increase that accuracy further: (1) increase the accuracy of the VLBA on Earth by adding more radio telescopes to it or (2) increase the distance between the two "eyes" or observation points by perhaps stationing these telescopes on Mars or in space. I think the Milky Way is supposed to be 100,000 light years in diameter so it might be worthwhile to try to increase the accuracy since there is more to measure in our galaxy.

[Dreamwoven]

The SOCIETY for POPULAR ASTRONOMY

Electronic News Bulletin No. 454 2017 October 8

IS MILKY WAY AN 'OUTLIER GALAXY'?
Yale University

The most-studied galaxy in the universe -- the Milky Way -- might not
be as "typical" as previously thought, according to a new study. The
Milky Way, which is home to the Earth and solar system, is host to
several dozen smaller galaxy satellites. Those smaller galaxies orbit
around the Milky Way and are useful in understanding the Milky Way
itself. Early results from the Satellites Around Galactic Analogs
(SAGA) survey indicate that the Milky Way's satellites are much more
tranquil than other systems of comparable luminosity and environment.
Many satellites of those 'sibling' galaxies are actively pumping out
new stars, but the researchers found that the Milky Way's satellites
are mostly inert. That is significant, according to the researchers,
because many models for what we know about the universe rely on
galaxies behaving in a fashion similar to the Milky Way. The SAGA
survey began five years ago with a goal of studying the satellite
galaxies around 100 Milky Way siblings. Thus far it has studied eight
other Milky Way sibling systems, which the researchers say is too
small a sample to come to any definitive conclusions. SAGA expects
to study 25 Milky Way siblings in the next two years.

[Danik 2016]

That is a bit disapointing. I first got interested in heavenly bodies after reading Viagem ao Céu(Voyage to Heaven), a children´s book by the Brazilian author Monteiro Lobato, an author of the 20ies. In this story the main characters travel to heaven and one of the places they visit is the Milky Way, which after that for me was unique.

[Danik 2016]

Aboriginal Australians Observed Red Giant Stars’ Variability

By: Javier Barbuzano | October 13, 2017

New interpretations of oral accounts by Aboriginal Australians show that they included references to the variability of red giants Antares, Betelgeuse, and Aldebaran.

"European astronomers realized that red giants changed in brightness in 1596, when David Fabricius registered the variability of the star Mira. Johannes Hevelius went on to calculate the amplitude and periodicity of Mira’s changes in 1662. But the oral traditions of Australian Aborigines could go much further back in time: they have inhabited the fifth continent for more than 65,000 years. Research examining oral tradition for geological events, such as volcanic eruptions or meteorite impacts, have shown that such oral traditions can survive for thousands of years."
http://www.skyandtelescope.com/astronomy-news/aboriginal-australians-observed-red-giant-variability/

[Dreamwoven]

Mars was this morning very bright, and its light steady, just above the horizon. Beautiful.

[Dreamwoven]

Modern astronomy tends to do that to our illusions. Sad but true.

[Dreamwoven]

There is a feeling that a new era is beginning in astronomy. Its best expressed in Astronomy Now: https://astronomynow.com/2017/10/16/gravitational-waves-from-colliding-neutron-stars-usher-in-new-era-of-astronomy/. I'm still not sure what this new era is. Perhaps it will gradually clear as more such colliding neutron stars become more frequent and more understood:

"A neutron star is formed when a massive star many times the size of our Sun explodes as a supernova, and what remains of the star’s core collapses under its own gravity. Neutron stars are only 20 or 30 kilometres across, but they pack the mass of an entire star inside them, with matter crushed so densely that all the protons and electrons merge to form neutron particles, hence their name. It’s often said that a teaspoon of neutron star material would weigh the same as Mount Everest. The estimated masses for the two neutron stars that merged in GW 170817 range between 0.86 and 2.26 times the mass of the Sun."

OK, Einstein predicted this almost exactly a century ago.

A kilonova is smaller and more concentrated than a supernova...

[Dreamwoven]

There are version of this across the astronomy pages. I chose Astronomy Now's version as being the least difficult to understand...