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Old 20-03-2012, 23:19
TelevisionUser
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Thanks for that link, Henry. The cruising to Mars is the easy bit but probably the mission's most vulnerable stage will be the atmospheric descent and landing using that previously untried "aircrane" system . My money's on another victory for the Great Galactic Ghoul http://en.wikipedia.org/wiki/Great_G...te_of_failures.

By coincidence, today's edition of Scott's legacy also covered Martian exploration amongst other things and it's well worth a listen:

Can the heroic age of Antarctic exploration show us the way back to the Moon and onto Mars?...As for Mars, the big questions are, is there life there now or did life ever evolve there? If it did originate on Mars, how different was it from life on Earth? If we found life did not arise there, we might wonder whether we are really alone in the Universe.
http://www.bbc.co.uk/programmes/b01dhrmj
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Old 21-03-2012, 15:44
HenryGarten
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This is a real wow
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Old 22-03-2012, 10:32
Bagpipes
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If you thought the Hubble Deep Field photo with 10,000 galaxies was impressive, then you'll like this. The European Southern Observatory has produced a new photo containing 200,000 galaxies. News story: http://scienceblogs.com/startswithab...tm_medium=link

Direct link to photo: http://scienceblogs.com/startswithab...o/eso1213a.jpg
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Old 23-03-2012, 10:00
HenryGarten
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Interesting site here. Tells us about various astronomy events.
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Old 23-03-2012, 10:34
balthasar
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Interesting site here. Tells us about various astronomy events.
That is a good find.
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Old 24-03-2012, 00:10
CLL Dodge
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Almost a new planet in the solar system:

http://www.bbc.co.uk/news/science-environment-17481911
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Old 24-03-2012, 00:52
atg
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Well it would be making a comeback as I believe it (and the other asteroids) was considered a bona fide planet after its discovery until they realised there were dozens of the things.
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Old 24-03-2012, 10:01
HenryGarten
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The ISS has to take evasive action to avoid a Russian spacecraft. See ISS crew take to capsules in space junk alert.
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Old 24-03-2012, 17:11
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Thank you for that interesting link, CLL Dodge. It turns out that Vesta was massive enough to evolve a spherical shape and have a differentiated interior http://www.planetary.brown.edu/pdfs/4373.pdf so that it became a proto-planet with a core, mantle and crust. It is quite possible that Vesta could have become another terrestrial planet by accretion were it not for the disruptive effects of Jupiter's huge gravity which ensured that the asteroids were constantly disrupted, couldn't accrete more matter and so became planetary builders' rubble.

Incidentally, it's received a hell of a battering over billions of years and some of those fragments of Vesta have found their way to Earth in the form of HED meteorities http://en.wikipedia.org/wiki/HED_meteorite (bits of the Moon and Mars have also come to Earth this way too).

And now for some news updates:

Europe's ATV space truck has blasted off from the Kourou base in French Guiana.

The robotic truck is heading to the International Space Station (ISS) with new supplies of food, water, air, and fuel. It is also carrying experiments and spares for the high-flying astronaut outpost.
Video: http://www.bbc.co.uk/news/science-environment-17470396

A Nasa spacecraft has found further tantalising evidence for the existence of water ice at Mercury's poles.

Though surface temperatures can soar above 400C, some craters at Mercury's poles are permanently in shadow, turning them into so-called cold traps. Previous work has revealed patches near Mercury's poles that strongly reflect radar - a characteristic of ice.
http://www.bbc.co.uk/news/science-environment-17470151

The planet Mercury was once an active and dynamic planet, according to new evidence from a Nasa spacecraft.

Data from the American Messenger probe shows that impact craters on the planet's surface were distorted by some geological process after they formed. The findings, reported in Science magazine, challenge long-held views about the closest world to the Sun.
http://www.bbc.co.uk/news/science-environment-17248776

Warp-speed planets ejected from the Milky Way Galaxy

New simulations suggest that planets, just like stars, could be booted out of their home galaxies at neck-breaking speeds of 30 million miles per hour. "We definitely see hypervelocity stars out there, and it's no stretch of the imagination to believe that there are hypervelocity planets out there as well," says lead author of the study Idan Ginsburg of Dartmouth College.
http://www.astronomynow.com/news/n1203/23warp/

New Orion capsule to be launched in 2014

Finally, it looks like the first NASA test of the new Orion capsule (to replace Space Shuttle) will take place in 2014 when an Orion capsule will be launched into Earth orbit by a powerful Delta 4 heavy lift launcher.

There is an SFX video of what should happen here: http://vimeo.com/38582552
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Old 25-03-2012, 09:39
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A new supernova has been found in the nearby galaxy M95, astronomers have confirmed, and it's one of the closest stellar deaths yet witnessed.

On March 16 professional astronomers and amateur observers detected the bright point of light on the outskirts of M95, a barred spiral galaxy in the constellation Leo, the lion. Since then, various teams have been watching the object closely.

Based on observations from around the world, the International Astronomical Union announced on Tuesday that the light is definitely an exploded star, now called SN 2012aw.
http://news.nationalgeographic.com/n...space-science/
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Old 01-04-2012, 23:35
Zaphodski
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Took my young daughter into the garden to see Saturn for the first time. She said it looked just like a star so I told her to now look at it though her starter telescope. Her reaction made my day (night...) and to cap it all I saw a shooting star a little later. A good night's stargazing had by all
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Old 06-04-2012, 19:39
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A humbling and beautiful image.

Astronomers have created an infrared map of the sky containing a billion stars: http://blogs.discovermagazine.com/ba...billion-stars/
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Old 13-04-2012, 13:37
Assa2
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Did anyone catch the Sky At Night 55th Anniversay program (part 1)? Quite amussing in a geeky kind of way but also some interesting little bits of info that I'd never heard before.

Such as that the 'observable' universe is estimated to be 45 billion LY across. Given that the most distant objects observed are quasars at around 13 billion LYs I'm not at all sure how this 45 billion LY figure was arrived at or even possible - it has something to do with inflation theory but still seems odd.

Also some of the terminology being used - "The Great Attractor" being what ever is pulling our local super-cluster of galaxy's towards it but which we can't see because it is hidden by "The Zone of Avoidance" - the area of the sky hidden behind the centre of the Milky Way. All sounds quite sinister to me. If I were a mega-super-massive molevolent entity hell-bent on eradicating all life from the universe and had found the last outpost of life left (us), it's exactly where I'd creep up from!
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Old 13-04-2012, 13:50
njp
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Did anyone catch the Sky At Night 55th Anniversay program (part 1)? Quite amussing in a geeky kind of way but also some interesting little bits of info that I'd never heard before.

Such as that the 'observable' universe is estimated to be 45 billion LY across. Given that the most distant objects observed are quasars at around 13 billion LYs I'm not at all sure how this 45 billion LY figure was arrived at or even possible - it has something to do with inflation theory but still seems odd.
This paper might help: Expanding Confusion: common misconceptions of cosmological horizons and the superluminal expansion of the Universe.

"We use standard general relativity to illustrate and clarify several common misconceptions about the expansion of the Universe. To show the abundance of these misconceptions we cite numerous misleading, or easily misinterpreted, statements in the literature. In the context of the new standard Lambda-CDM cosmology we point out confusions regarding the particle horizon, the event horizon, the ``observable universe'' and the Hubble sphere (distance at which recession velocity = c). We show that we can observe galaxies that have, and always have had, recession velocities greater than the speed of light. We explain why this does not violate special relativity and we link these concepts to observational tests. Attempts to restrict recession velocities to less than the speed of light require a special relativistic interpretation of cosmological redshifts. We analyze apparent magnitudes of supernovae and observationally rule out the special relativistic Doppler interpretation of cosmological redshifts at a confidence level of 23 sigma."
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Old 13-04-2012, 20:11
Assa2
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This paper might help: Expanding Confusion: common misconceptions of cosmological horizons and the superluminal expansion of the Universe.

"We use standard general relativity to illustrate and clarify several common misconceptions about the expansion of the Universe. To show the abundance of these misconceptions we cite numerous misleading, or easily misinterpreted, statements in the literature. In the context of the new standard Lambda-CDM cosmology we point out confusions regarding the particle horizon, the event horizon, the ``observable universe'' and the Hubble sphere (distance at which recession velocity = c). We show that we can observe galaxies that have, and always have had, recession velocities greater than the speed of light. We explain why this does not violate special relativity and we link these concepts to observational tests. Attempts to restrict recession velocities to less than the speed of light require a special relativistic interpretation of cosmological redshifts. We analyze apparent magnitudes of supernovae and observationally rule out the special relativistic Doppler interpretation of cosmological redshifts at a confidence level of 23 sigma."
17 years ago when I was studying this sort of thing at university, that might have all made sense. Actually, no it wouldn't because a) none of this had been hypothosised then and b) I'd have been in the pub rather than at the lecture I never really found cosmology that interesting mainly because it was mostly theoretical, relied heavily on advanced maths which I couldn't do and was full of assumptions which had no logic to them.
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Old 20-04-2012, 00:16
epicurian
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Dutch astronaut André Kuipers has a stunning perspective on the planet we call home.
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Old 20-04-2012, 00:39
HenryGarten
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Old 20-04-2012, 02:32
Blackjack Davy
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Venus is really bright in the night sky and it's visible all night long apparently which is really unusual I don't think I can ever remember that happening before. If it was christmastime we'd get reports of people saying the Star of Bethlehem had reappeared...

... I flogged my pair of binoculars a while ago as I hadn't used them in donkeys years, I could really do with them now!
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Old 20-04-2012, 05:42
HenryGarten
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Venus is really bright in the night sky and it's visible all night long apparently which is really unusual I don't think I can ever remember that happening before. If it was christmastime we'd get reports of people saying the Star of Bethlehem had reappeared...

... I flogged my pair of binoculars a while ago as I hadn't used them in donkeys years, I could really do with them now!

Yes Venus is exceedingly bright just now. Venus sets around midnight. If people have a look at stellarium they will find it is setting around midnight just now.

I am sure that someone like Carlos could tell you immediately when the last time we saw Venus "up all night" as you put it.

There are plenty of articles on the subject should you care to look. Venus is heading toward a transit of the sun on June 6. That is only 47 days away. No one on Digital Spy will ever see the one after that.
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Old 20-04-2012, 08:45
HenryGarten
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Venus is really bright in the night sky and it's visible all night long apparently which is really unusual I don't think I can ever remember that happening before. If it was christmastime we'd get reports of people saying the Star of Bethlehem had reappeared...

... I flogged my pair of binoculars a while ago as I hadn't used them in donkeys years, I could really do with them now!
Here is an article on this apparition of Venus

and another
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Old 20-04-2012, 11:59
Elissa Richards
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I finally got out last night for a little viewing after a week of cloud, the weather has been terrible round here recently. Of course with Venus being so prominent I had to take a little peek, I've been sketching it's phases since Jan and quite enjoying seeing the gradual changes. Someone mentioned how often is Venus viewable so far into the evening....well in short it's roughly every 8 years. There's various factors involved but a key point is it's angular separation which at the start of the month was a whooping 41 degrees, placing it very high in the sky when the sun sets. This high value isn't so common and occurs every 8 years. Chatting to various bods in my tutor group a few of us tried blue and violet filters whilst observing Venus. I got little hints of cloud structure but struggled to see anything clearly defined, maybe others have had better luck.

I did manage to locate her though at midday most days in March when we had the clear weather, that was pretty memorable as it's the first time I've found her during the day so easily. I can't wait to see the transit in June, I've got the day off, a new solar mask for my dob and I'm praying we're going to get clear skies!!

This month though my main aim has been galaxy hunting in Leo and Virgo, the weather hasn't been too great but i've managed to observe and sketch all their constituent Messier objects. I quite enjoyed working my way down Markarians Chain observing and sketching the larger galaxies. It's defo a worthwhile target for anyone with a scope, I think anything over a 5 inch scope should start to show up the brighter galaxy cores. Here's a pic of the little beauties

http://upload.wikimedia.org/wikipedi...nterWilson.jpg
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Old 20-04-2012, 12:19
len112
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What happened about the remastered Apollo 11 footage which was going to be released to celebrate the 40th Anniversary ?
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Old 20-04-2012, 14:29
Elissa Richards
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What happened about the remastered Apollo 11 footage which was going to be released to celebrate the 40th Anniversary ?
I didn't realise they were doing that....surely that would've been in 2009 that news was kicking around? Do some digging on the net...
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Old 20-04-2012, 14:41
Carlos_dfc
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Venus is really bright in the night sky and it's visible all night long apparently which is really unusual I don't think I can ever remember that happening before.
I am sure that someone like Carlos could tell you immediately when the last time we saw Venus "up all night" as you put it.
Thanks Henry...
Venus apparitions repeat in cycles of 8 yrs (as Elissa Richards has already pointed out) - and the fact that it's bright and visible until after midnight, is indeed down to it's distance (angular separation) from the Sun.
Another big factor is the time of year - i.e. the Sun setting later at night.

In the winter - with the Sun setting earlier, and at a shallower angle - even if Venus was the same angular distance from the Sun, it would set far earlier, and much sooner after sunset.

With Venus, there's also the '36 day rule' - where significant events follow after 36 day periods....
Greatest Eastern elongation was the night of March 25th/26th this year.

Venus at it's brightest is 36 days later - April 30th/May 1st.

Then inferior conjunction - 36 days later - the night of 5th/6th June.
This year - as Henry mentioned - venus transits the face of the Sun, and from UK the end of the transit - Venus moving slowly off the face of the Sun, will be happening as the Sun rises on the 6th.

36 days later - Venus reaches it's brightest morning apparition on 12th July

And again, another 36 days until Venus reaches it's greatest Western elongation. (17th Aug)

Then there's a 440 day period until the next Eastern elongation - when the 36 day periods will begin again. A total of 584 days (about 1yr 7½ months) for the whole cycle.
Over a period of 8yrs, Venus will go through 5 cycles, 5 periods as an 'evening star', and 5 periods as a 'morning star'. Then when the 8 year cycle completes, it will be back in pretty much the same position, on the same date.
April 20th, 2020, Venus will be pretty much where it is tonight.

Looking ahead though - next evening apparition will be from late summer 2013, through autumn (max eastern elongation late Oct/early Nov) and into winter - Unfortunately, it'll be low in the sky, like the Sun, and setting at a shallow angle.

Spring and summer 2015 though, will be another high and late evening apparition, and Venus will be visible until after midnight towards the end of May, and well into June.

And remember how Jupiter passed only 3º away from Venus, earlier this year..??
June 30th 2015, Jupiter will pass less than ½º from Venus
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Old 20-04-2012, 15:04
xxtimbo
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very bright star in the sky last night at 11 pm ... looking NW
could it be Jupitor ?
or maybe a space platform ?
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