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What's next? Calling the sun something stupid like "Sol"?

Just in case you're not being sarcastic, as our Solar System's planets are actually named after Roman gods, the name for our Sun would be Sol just as Earth is actually called Terra.

For a list of names, see this compilation.

That's the name of the planet orbitting inside of Mercury's orbit.

No, seriously!

*Any* atmosphere on a sub-500km wide moon would be significant. I'm looking forward to a more complete report as more information comes in.

Why am I suddenly hungry for Mexican food?

At least I know i wasn't the only one who thought it was sun and not sol

Uh, the glaciers on Antarctica are continuously moving, and rebuilding. Snow falls year after year, after year, and the glaciers keep moving, and rebuilding.

They are continuously moving, but the sea ice shelf is holding back the glaciers from moving a lot faster, which has allowed so much ice to form on Antarctica. If the sea ice melts, all the glaciers would be able to "dump" their ice (which is currently over land) into the oceans, which would raise the water levels. It is not necesarrily the melting of the ice over Antarctica itself that will cause the sea levels to rise.

And, yes, the glaciers are moving faster. And, yes, this could - eventually - effect water levels. And, no, there is no possible way that this would happen within 10 years time. There is a mere outside chance that it may happen over the next 200 (two hundred) years.

Its not that it will occur in 10 years, but if we don't change the way that we currently use fossil fuels etc... it will be very hard to stop Antarctica melting within that 200 year timeframe, due to positive feedback in out atmosphere. (look to Venus for how positive feedback can occur, and how its atmosphere ended up as a 400 deg C maelstrom, as opposed to Earth, an essentially similar planet)

What we don't know is how much we can effect this change - in either direction.

What we do know is that CO2 levels are the highes they have been since known atmospheric history (420,000 years) and that CO2 levels have had a close correlation to temperature over that period. (Although we dont know that they are causally linked.)

Whilst we don't know how much we can affect this change, we do know that if we carry on as we are, things will certainly not get better, and warmer weather is not necessarily better, ~14,000 excess deaths occurred from heat related problems in France during Summer 2003, which is a lot more than the ~3,000 who died in 9/11. (Although 9/11 showed how bad the USA's homeland security was at the time - all the flights took off from US airports on internal flights.)

Ever heard of the Sun?

To do serious damage, we'll need a rock at least a few hundred meters across.

It depends on what you call "serious damage". The Tunguska event blasted thousands of square kilometers of Siberian forest and it is estimated that it was a meteor just 60 meters wide.

A similar impactor hitting a populated area would decimate a whole metropolis or even a small US state. I would call that "serious damage".

I thought Venus was still active? http://www.nineplanets.org/venus.html " Data from Magellan's imaging radar shows that much of the surface of Venus is covered by lava flows. There are several large shield volcanoes (similar to Hawaii or Olympus Mons) such as Sif Mons (right). Recently announced findings indicate that Venus is still volcanically active, but only in a few hot spots; for the most part it has been geologically rather quiet for the past few hundred million years."

The death star is in orbit around Saturn

Rather remarkably, the Death Star does actually appear to be in orbit around Saturn, but it's not Titan, it's Mimas.

http://www.nineplanets.org/plea.html

There are those who have different points of view about what our goals should be in space. Some are interested in science or just the beauty of an alien landscape; they are satisfied looking vicariously through the eyes of a machine; others feel the need to actually walk those alien landscapes, or send human proxies. Still others believe that human destiny is in the stars and we must expand into the universe to survive. I guess we need to work together, and tolerate each other's motivations.

Benjamin Franklin put it more succinctly: "We must all hang together, or most assuredly we shall all hang separately."

Who said anything about comets? Are you going to go to the Oort cloud and bring them back? WTF?! If you've got that much energy then just do whatever you're going to do directly on Mars. Don't use it on some fantastically stupid plan to bring comets from outside the solar system.

He has certainly been under appreciated since Copernicus.

See this for more information about him, and this for some similar views.

He has certainly been under appreciated since Copernicus.

See this for more information about him, and this for some similar views.

He landed on Japetus (Iapetus if you prefer). In the middle of the trailing (bright) side of Japetus to be precise.

I guess they changed it for Jupiter since they got those cool CGI effects of jupiter from a scientific project to simulate its athomosphere. ;-)

There are runaway models that support a self feeding or positive feed back model for temperature rise. Astronomers have been trying to explain Venus' atmosphere and temperature for decades. The most common theory is the Green House effect.
Venus Facts.

While I believe that there are greater climatological forces (greater than Yuppies with SUV's) at work which cause up and down cycles in global temperature; life in general has had a very marked hand in contributing to these changes. The most radical planetary change attributed to life forces has to do with early bacteria and algae giving the earth its oxygen rich atmosphere.
Early life formsand O2

I do support using more efficient energy technologies as these not only help slow down CO2 emissions (which may or may not contribute to global warming) but more importantly reduce sulfur, ozone, and nitrate emissions which are known to cause acid rain and contribute to air pollution. I have been doing my part by replacing old light bulbs with energy efficient ones and by better insulating my house and running an attic fan in stead of the AC when weather permits, etc. If everyone makes lots of little changes then this will have a big impact on our overall quality of life. I'm not talking about shivering in the corner during the winter because you shouldn't run your heater but the stakes are too high not to pay attention and try to take the best actions even if the data is incomplete. Baby steps.
Climate change

The picture on the Discovery Channel coverage is not the asteroid in question. I know this means I need to get out more, but I instantly recognized that picture as 243 Ida and its tiny satellite Dactyl.

But even in your own statement you show the problem: Terms like "large" are relative. They're comparative.

A "large dog" is likely to be much smaller than a "large boat," is likely to be much smaller than a "large house," is likely to be much smaller than a "large planet," is likely...

In fact I threw in all those "likely" statements precisely because the definition of "large" is so arbitrary. Is 1,000,000 a large number? It sure is if compared to .000001. It's not so impressive compared to 999,999 and it's small compared to 1,000,000,000,000.

In order for size to be a valid criteria you would have to pick specific size over which an object must be to be considered a planet. If we're talking diameter, Pluto is roughly half the size of other objects we call planets. Then again, the moon of Calisto is roughly the same size as the planet Mercury. If we're talking mass, then it's roughly 25 times less massive than Mercury--but then again Mercury is 15 times less massive than Venus, 18 times less massive than Earth and over 300 times less massive than Neptune. What is our cutoff point? And more importantly, how did we arrive at it? If we're going to assign it arbitrarily right now then we can decide for ourselves whether or not it would be a "reasonable definition" to include objects similar to Pluto and the debate begins anew.

(For those interested, the numbers at http://www.nineplanets.org/datamax.html were used for comparisons and my calculations are probably wrong. :P)

Actually, Europa does have an atmosphere, at least according to the JPL. This site also has some good quick facts about Europa.

One of those universe/solar system simulations - I forget the name.
Possibly because there's more than one name to forget... (=

Let's see, for general touring around the Solar system and neighborhood, there's nothing quite like Celestia. Hours of fun, and very pretty to look at.
Noctis is also similar, but set in a fictional universe.
For more pretty pictures, but less interactivity, see The Solar Journey homepage or the Solar System Simulator. Also The Nine Planets for Kids.
Naturally, kids aren't that interested in just flying around. Well, Orbit lets them blow each other up in space, but with realistic physics and visuals. Once that gets boring, you can let them fly a space shuttle to the ISS with Orbiter. Beware, though. Orbiter is no simple game - you actually need to know how space flight works. There's also the Microsoft Space Simulator, which Orbiter has more or less superseded.

If you're not looking to get that far off the ground, FlightGear's an excellent flight simulator in which you can fly everything from the original Wright Brothers' craft right up to concept superplanes.

More links, mainly astronomy related, here, here, here, here, and here.

Finally, you might wish to try browsing the Tucows Games site and Freshmeat's game section (you'll need to login to make full use of Freshmeat).

Good luck, have fun searching.

One of those universe/solar system simulations - I forget the name.
Possibly because there's more than one name to forget... (=

Let's see, for general touring around the Solar system and neighborhood, there's nothing quite like Celestia. Hours of fun, and very pretty to look at.
Noctis is also similar, but set in a fictional universe.
For more pretty pictures, but less interactivity, see The Solar Journey homepage or the Solar System Simulator. Also The Nine Planets for Kids.
Naturally, kids aren't that interested in just flying around. Well, Orbit lets them blow each other up in space, but with realistic physics and visuals. Once that gets boring, you can let them fly a space shuttle to the ISS with Orbiter. Beware, though. Orbiter is no simple game - you actually need to know how space flight works. There's also the Microsoft Space Simulator, which Orbiter has more or less superseded.

If you're not looking to get that far off the ground, FlightGear's an excellent flight simulator in which you can fly everything from the original Wright Brothers' craft right up to concept superplanes.

More links, mainly astronomy related, here, here, here, here, and here.

Finally, you might wish to try browsing the Tucows Games site and Freshmeat's game section (you'll need to login to make full use of Freshmeat).

Good luck, have fun searching.

Nine Planets has a big list of all spacecraft - past, current and future (although it is a little out of date).

and people are tougher than you think.

That argument works fine on Earth, where you could fall out of your ship, or get stranded on an island and live off the land. Mars has virtually no atmosphere (7mbar, only 0.15% oxygen), and the average temperature is -55degC. There is no potential for "living off the land" without serious engineering work. Man is fairly tough in his natural environment, but this is a whole new ball game.

More info is here.

And while you're at it, you may want to check out Celestia, a 3D space simulator.

Well, yes. But with Europa, there's some (perhaps miniscule) chance that there could actually be life there...

According to Nineplanets, Europa may be the only body besides Earth that has significan't quantities of water.

The gas velocity is depedant on the Ideal gas law, here solved for velocity.
v = sqrt(3 R T / M )

where v is the velocity,
R the Ideal Gas constant, (0.08206 L atm / kg Kelven),
T the surface temperture in Kelvin,
and M the molar mass ( 2 * 16 for oxygen, 12 + 2*x16 = 44 for CO2 )

and the escape velocity is v = sqrt(2 Ga M/R)
where; Gc is Newton's constant ( 6.6715 E - 11,
M the mass of the Object,
R the surface velocity.

Basicaly, this means the larger (and cooler) an object is, the more atmosphere it can support.
Incidently, once an object gets an atmosphere, the surface temprature (sun side), is likely to be cooler, allowing more of an atmosphere to be supported.
Solving for Titan, and Mars are left as an exersize for the interested reader, Nine planets will give the remaining values needed

Here is a link to 2001 KX76 last year's big Kuiper belt object. And here is some more background infor on the Kuiper belt in general.

The Kuiper Belt is a disk-shaped region past the orbit of Neptune roughly 30 to 100 AU from the Sun containing many small icy bodies. It is now considered to be the source of the short-period comets.

P.S. Google's your friend.

Hope this helps.
-Daniel

Yes, life seems to be quite common.
Let me count the potential candidates i heard of so far:

- Earth
- Mars
- Venus
- Europa (no, not the continent you US-centric /.ers)
- and now even Pluto...i def counted this one out.

My guess was always that life must be a rather common thing. If you look at all the impossible places where life found its way on Planet Earth...

Venus has little hydrogen in its atmosphere, which is mostly carbon dioxide and nitrogen. Carl Sagan is credited with suggesting the use of algae to begin terraforming Venus, but it was later realized that this, by itself, would probably not work.

The problem is that the atmosphere at the surface of Venus has about 90 times the pressure of Earth, and it is so hot at the surface that any oxygen produced by the algae would be burnt back into CO2 when they die and settle to the hot lower atmosphere. Even if we could magically remove 98% of Venus' atmosphere, I once heard it would take tens of thousands of years for the planet to radiate enough heat to space for humans to walk on the surface.

We should concentrate our efforts on Terraforming our own planet. There are plenty of recently created deserts and other wastelands that our technologies (including algae!) could make more livable for us, starting today.

I grew up at a great time to be a science nerd, I remember fondly the Time-Life Science Books, newspaper articles and television coverage of the Apollo missions, playing with a chemistry set...

I'm not sure what science kids resources on the net will live up to those standards. A couple that I like are Nine Planets and Science Toys you can make with Your Kids, anybody got any others?

Hmm, I thought that Jupiter was just a Ball of Gas - 'Crashes' may be the wrong word!!, 'To be consumbed by' may be more appropiate!!

Don't think that's correct. You can find more info on this here:
http://www.nineplanets.org/pluto.html and here:
http://www.bbc.co.uk/planets/features.s html