5 ms·
Yawp. Fast factsheet here: http://nssdc.gsfc.nasa.gov/planetary/factsheet/marsfact.html http://nssdc.gsfc.nasa.gov/planetary/factsheet/marsfact.html For starte
by jpxxx 14y ago
Yawp. Fast factsheet here: http://nssdc.gsfc.nasa.gov/planetary/factsheet/marsfact.html http://nssdc.gsfc.nasa.gov/planetary/factsheet/marsfact.html
For starters, the remaining atmosphere on Mars is extraordinarily thin. Go to the top of Mt. Everest. Then go four times higher than that. That's the atmospheric pressure at "sea" level on Mars.
It's apparently relatively easy to determine atmospheric composition from afar, and of the atmosphere remaining on Mars, 210 parts per million is water. I have not done the math myself, but I'm assured the total "depth" of water left is measured in microns.
It's really dry. It's really cold. And we'd pop like a balloon stepping outside.
As for how much water is frozen below? SHRUGGGGGG Anyone could make a career answering that. The biggest confounding factor is that the planet is substantially covered in dust, many meters thick in places. It makes remotely sensing what's underneath a real pain in the ass.
The most solid answer so far appears to be "there is a nontrivial amount of ice below the ground". Think "enough to fill the great lakes".
- waterlesscloud 14y agoOne minor point- the temperature on Mars makes gigantic wide swings. It can get to be pretty warm there. I believe the record high is 81 degrees F, which is what it is this afternoon in Los Angeles. Of course, it also gets down to -200 F, so the swings can be huge. Temps above freezing have been reported by Curiosity, which is interesting in itself.
- jpxxx 14y agoI did not know that, thank you! I can only imagine that engineering a rover to withstand those temperature swings is a pain in the ass.
- waterlesscloud 14y agoHere's the official site for Curiosity's weather reports. http://cab.inta-csic.es/rems/marsweather.html http://cab.inta-csic.es/rems/marsweather.html
- e2e8 14y agoSecond minor point: A human stepping out into vacuum does not "pop like a balloon." Death comes quickly but in a more mundane fashion. http://imagine.gsfc.nasa.gov/docs/ask_astro/answers/970603.html http://imagine.gsfc.nasa.gov/docs/ask_astro/answers/970603.h...