..just a Cobra MkIII refueling.
Comet Lovejoy survives brush with fiery solar death
Suicidal comet Lovejoy has survived its brush with death in the furnace of the Sun, emerging from behind the star in one (smaller) piece. Most space boffins thought that the comet, composed of ice and rocks, couldn't survive its trajectory so close to the heat of the Sun - and expected Lovejoy to disintegrate. But instead, …
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Monday 19th December 2011 15:47 GMT JeffyPooh
"...the several million degree solar corona..."
The corona is essentially a hard vacuum. If it wasn't a hard vacuum, then the 'atmospheric' drag would have stopped the comet dead in its tracks. The point is that the "several million degree solar corona" is a bit of a red herring. The big bloddy hot 6000° star filling the comet's field of view is real enough. But the "million degree" corona ^h^h^h^h^h^h hard vacuum is mostly foolish nonsense.
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Monday 19th December 2011 16:27 GMT Ken Hagan
What's the surprise?
We know that some other objects with highly elliptical orbits are dirty snowballs, but no-one's actually tested this one. The available evidence prior to this observation is simply that it is on a highly elliptical orbit that takes it very close to the sun. *Unless* we have some reason to believe that this is its first ever circuit, that means we know it has survived such close approaches before.
Therefore, what is the surprise?
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Monday 19th December 2011 22:25 GMT Remy Redert
Re: What's the surprise?
The assumption up until now was that a comet of its size, having been repeatedly passed by the sun in the past and becoming smaller in the process every time, would not survive such a close encounter with the sun.
Now in a few thousand years when it comes back again, then we'll be able to get a really good understanding of just how these things work, because we can observe the same comet having another go at the sun.
Or we could develop decent spacecraft by then and go look it up with a probe while it's still far far away.
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Monday 19th December 2011 22:51 GMT Annihilator
the surprise
Because it's a "dirty snowball" that's constantly shrinking due to it's tail. If it's got a tail, it's losing mass and stability, and the prevailing opinion was that this one had shrunk so small as to not survive going so close to the sun *this* time. No assumptions were made on it being a first time pass (a hyperbolic comet - very rare) and how well it survived any previous times has little to do with how well it survives this or the next time.
There's only three fates for comets - extinction (nothing left in them, but stable enough that they're just a lump of rock - effectively an asteroid), break-up/disintegration (what was expected here) or hitting something else like a planet, like the one that we got a cracking view of hitting Jupiter back in the 90s.
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Tuesday 20th December 2011 17:12 GMT Ken Hagan
Hmmm. So our first look at this comet happens to be its last.
I suppose (over the set of all comets) that this is bound to be the case *eventually*, but I would still say it was a rash assumption for any given comet, regardless of what they are made of. Perhaps the astronomers need to talk to the geologists about Deep Time.
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Tuesday 20th December 2011 01:21 GMT Anonymous Coward
@Ken
Well, I'm venting assumptions myself here as well, but my bet would go to "We couldn't possibly have been wrong?!".
And my conspiracy theory explanation for that is "money". Isn't it slightly surprising to see how all of a sudden many "deep space victory stories" get released in a very small time frame ?
Where a lot of those stories come from NASA; an agency "sponsored" by the government? Well, I wonder when their government decides on the next annual budget...
With that in mind I don't think it should come as a surprise to see people being or acting surprised with these results. It sells a lot better (with their bosses that is) than "so we made a mistake in our hundred thousand dollar investigation, we'll do better next time!".
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Monday 19th December 2011 22:53 GMT Pascal Monett
So the core is activated now ?
And soon we will see the heat bloom of the subterranean energy source that will revive the alien life-form contained within before re-orienting the comet's course to collide with Earth so as to start the second phase of the infestation.
Now we know why the Mayans didn't bother counting beyond 2012.
It's all true !! Run for the . . . oh wait, that'll be useless anyways.
Oh well, better stock up on champagne then, in order to get ripped to shreds in style.