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Rosetta Probe Reveals Martian Cloud Systems
MattSparkes writes "The ESA's Rosetta probe swooped around Mars on Sunday, completing a key manoeuvre in its 10-year mission to land on a distant comet. The 3-tonne probe came within 155 miles of the planet's surface, and took some incredible images that reveal cloud systems on the planet. "At this time of the Martian year, a large fraction of Mars' atmosphere is evaporating from the southern polar cap and will migrate to the northern polar cap during nothern winter. Over most of the Martian disk one can see large cloud systems.""
I really don't get this first post thing? Where's the enjoyment?
Matthew Sparkes
all the more tantalizing. Even if the only thing we did was use Mars as a test bed for climatological effects on Earth. It's an engineering/scientific endevour that appears just out of our reach...but only just.
Then again...it may be that the phrase, "It's not nice to fool with Mother Nature" applies to the Solar System as well.
A goal is a dream with a deadline
That's how those words are spelt in England, in English. Tonne is a metric measurement. Manoeuvre is also correct. Why go out of your way just to display your ignorance?
Don't knock it until you've tried it.
You unbelievers! See how global warming on earth has now started to affect other planets!
I always wonder how much time is spent trying to make a name have a cool acronym
"Luck is a tag given by the mediocre to account for the accomplishments of genius." -Heinlein
Terraforming makes for nice fiction, but misses the mark that the planet must _already_ be earth-like enough. Or you must be capable of the godlike feat of increasing its mass a few times, changing its rotation speed, melt its core again, etc. Otherwise the same reasons that shafted its original atmosphere, will shaft whatever atmosphere you create.
:P
E.g., for Mars, it's simply too small and it cooled down too fast. (Well, just right for its size and mass, actually.) So the magnetic field is much too weak to shield it from solar winds, and its low gravity doesn't do much to hold an atmosphere either. So it just escaped and was swept away into space. Any atmosphere you're going to create there while terraforming, is going to just go away too.
The only way to terraform Mars would be to (A) increase its size to something more earth like, _and_ (B) melt its core again, and (C) bring from somewhere all the elements that got swept away in the past, e.g., a metric buttload of hydrogen, and maybe (D) fiddle with its rotation speed too, so that core you just melted generates enough magnetic field. Does it sound like pure SF yet?
Heck, _if_ anyone were to start terraforming anywhere, the easiest start wouldn't be Mars, but Venus. It's about the same size as Earth, about the same density too, it still has a magma core, and it's in the right band to support life too. Why Venus ended up the poisonous wasteland instead of Earth-like? It spins way too slowly. So it pretty much doesn't have any magnetic shielding against the solar winds. The very weak magnetic field it has is mostly due to interaction between solar winds and its atmosphere, rather than an internal dynamo. So without shielding, it pretty much lost all its hydrogen. Whatever water it had evaporated, got ionized sooner or later and the hydrogen was just swept away. So now the atmosphere is almost pure CO2 and some nytrogen.
By now you probably get the idea that terraforming even Venus is just nuts. You'd have to bring a heck of a lot of hydrogen from somewhere else (from where and at what cost?) _and_ give it a good spin (with what energy and just how?) _and_ somehow start some plate tectonics mechanism to get the convection currents going in the planet and start its dynamo (again, how?) _and_ oh, for that matter, get rid of all that carbon in the atmosphere or all the water will just boil off. Pretty tall order, don't you think?
So "appears just out of our reach...but only just" must be the understatement of the century. Maybe if by "just" you mean "not in another million years."
A polar bear is a cartesian bear after a coordinate transform.