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[hobbes]

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Ah now, that's cool. Good spot CV. Unfortunately my scope isn't big enough toresolve to that size. I can just about make out the bands and the spot.

[Ginger Yellow]

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Today's APOD, our first good look at Vesta:

[Various Artist]

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For anyone in the UK or something very near it, I've just spotted a fabulous conjunction of Venus and Mars going on right this minute in the western sky — not far to the lower-right of the crescent moon too, which is itself in conjunction with Uranus (just above-left of the moon's disk), not that you'll see that unless you've got a telescope. The Sun (and Neptune) is just below the horizon on the same axis.

[hobbes]

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And directly opposite is Jupiter, too.

[Rogin the Armchair fan]

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We caught the Mars-Venus spectacle last night, too, just got lucky there was a break in the cloud at the right moment after sunset. My photos of it are rubbish otherwise I'd post them up.

As Venus is closer to the sun than we are, and Mars is further away, we're currently sort of looking in, over Venus's shoulder, at Mars which is right over the other side of the sun from us, I presume?

[Various Artist]

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That's a very good way of putting it Rogin, exactly! I found looking at them 'together' last night, knowing one is nearer to us than the Sun and the other further away, was an ideal time to try to wrap one's head around the three-dimensional layout of what appears to us (of course) as a 'flat' spectacle.
Knowing the sun was almost straight below the clustering, below the horizon, was easy to visualise thanks to the sharp crescent of light hitting the moon from one side, and indeed Venus should have appeared as a crescent too but my eyes/binoculars aren't completely up to distinguishing that due to its overall bright glare. So it's relatively simple to picture oneself gazing into the inner part of the solar system, swinging past Venus down to the sun — after which it's just a matter of comprehending how Mars is much further beyond, merely sweeping past in the background in the same line of sight. It's quite clearly fairly small and unimpressive in appearance right now, which helps, and not just in comparison with the blaze of Venus — if we were on the same side of the sun the Red Planet would appear considerably more striking. But then of course if would have to appear on the far side of the sky from Venus because the only way we could see both would be due to lying in between them. So win some, lose some.

If Jupiter, meanwhile, were a football, Leo the Lion would presently be doing keepy-uppies with it.

The weather down Cardiff way is filthy today: such has been the rain, the lawn is turning into a pond. The chances of my seeing anything astronomical whatsoever tonight are about as likely as my being abducted by little green men, so I'm glad I happened to look out last night, when by some miracle we got an entirely clear sky all evening.

[evilC]

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This is more a speculative question than real news, but...

That 'haze' or plumes that have been observed on Mars.- With Mars' thin atmosphere, couldn't it simply be that a meteor has broken up due to Mars' gravity and that more (small) pieces have made it to the surface - in a cluster - than would be the case if it was heading to Earth? This could presumably kick up a hell of a lot of dust, if it happened in a dry area. It could also account for the repetition of the phenomenon.

Does this sound feasible?

[hobbes]

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I'm not sure, but I think the impact would have to be so big to create a plume of dust that would reach not far off escape velocity, would have left a big Crater and a hell of a flash.

[hobbes]

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Having had a quick look, they're not sure what caused it. Or even if it was dust.
Could have been aurora as well as ice/dust/methane vapour etc.

[Ginger Yellow]

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Phil Plait discusses the plumes.

And more imagery courtesy of the ESA

[Ginger Yellow]

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Ceres gets a close-up:

[Diable Rouge]

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After nine and a half years, the New Horizons spacecraft will finally reach Pluto on Tuesday week. One can only imagine the patience of NASA scientists, planning a mission for a decade, while knowing that even the smallest mistake could see all their preparations wasted.

[hobbes]

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Planning a mission for 2 decades more like.
These things can be 10 years from idea to launch too.

In fact, I've just checked. It was given the green light in 2001. So add a couple to that for getting together the justification to present to NASA and you're looking at 16 years from conception to pay off.

[G-Man]

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So, did anyone catch the Venus/Jupiter get-together?

[Ginger Yellow]

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Pluto and Charon, 2 days out:

[Rogin the Armchair fan]

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Is that a composite photograph or do they actually orbit each other that close together?

[Southport Zeb]

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It's a composite - Pluto's diameter has now been measured as 2370km, whilst Charon orbits about 18 000km away

[Janik]

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The moon is 150m km from the Sun give or take, and yet they occasionally appear next to, or even in front of each other from certain vantage points.
i.e. it is not necessarily a composite.

[Southport Zeb]

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New Horizons is approaching the Pluto system from above the plane in which the moons orbit, so I don't think it could take a photo of Pluto and Charon that close together.

Link to a colourised version, confirming it is a composite

[Ginger Yellow]

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It's a composite. Technically, they've been "enlarged, stacked, and deconvolved".

[Various Artist]

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Still an incredible sight — all my life Pluto and Charon have been hidden behind a veil of distance, the Patrick Moore astronomy textbooks I grew up with in the early '90s able to show them as only a handful of bright pixels and even more recent shots barely able to distinguish the vaguest areas of light and darkness. So to suddenly witness them appear at long last from the depths of space as real, solid, round, rocky, cratered (minor) planetary bodies is just amazing to me. It feel like one of the last significant frontiers of our solar system has fallen. Thanks for posting GY, and to SZ above for the extra link.

[Come along, Min]

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For some reason, I never really imagined Pluto would have so much character.

[Rogin the Armchair fan]

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This probably sounds just as dumb as my question above, but one of the things that's surprised me most is how bright the surface appears. I'd thought, that far from the sun, Pluto would be illuminated as if by moonlight on Earth, but the sunlight there seems still very bright indeed.

[Janik]

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I was wondering about that as well. Long exposure time and post-processing of the image seem the most likely explanations.

[Guy Profumo]

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Rogin the Armchair Fan wrote: This probably sounds just as dumb as my question above, but one of the things that's surprised me most is how bright the surface appears. I'd thought, that far from the sun, Pluto would be illuminated as if by moonlight on Earth, but the sunlight there seems still very bright indeed.

It's this bright on the surface!

http://www.space.com/29600-pluto-time-nasa-new-horizons.html