Mars Polar Cap Mystery Solved 77
Matt_dk writes "Scientists are now able to explain why Mars' residual southern ice cap is misplaced, thanks to data from ESA's Mars Express spacecraft (the same probe running the 'Mars Webcam'). It turns out the martian weather system is to blame. And so is the largest impact crater on Mars — even though it is nowhere near the south pole. Like Earth, Mars has frozen polar caps, but unlike Earth, these caps are made of carbon dioxide ice as well as water ice. During the southern hemisphere's summer, much of the ice cap sublimates, a process in which the ice turns straight back into gas, leaving behind what is known as the residual polar cap. The mystery was that while the winter cap is symmetrical about the south pole, the residual cap was offset, and scientists couldn't figure out why."
Martian atmosphere (Score:5, Insightful)
I don't know why, but I always though of Mars as a planet without an atmosphere. Perhaps like our Moon, just much bigger. So when first reading the article, I thought that as soon as the carbon dioxide gas sublimated, it would be lost to space.
However, the atmosphere is just really thin: http://starryskies.com/solar_system/mars/martian_atmosphere.html [starryskies.com]
So, thanks to Slashdot, I once again expand my knowledge of the universe and learned something new today!
Maybe now the ending scene in Total Recall makes some more sense? I'll have to rewatch it and see...
Re:Martian atmosphere (Score:3, Insightful)
The ending of Total Recall makes perfect sense. It only causes problems if you insist that the ludicrously over-the-top secret agent action hero scenario was actually real, as opposed to what your man had in fact paid for at the very beginning.