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Mars Harder and Colder Than Previously Thought
coondoggie writes "Turns out that the surface of Mars is stiffer and colder than previously thought. New observations from NASA's Mars Reconnaissance Orbiter indicate that any liquid water that might exist below the planet's surface and any possible organisms living in that water would be located deeper than scientists had suspected. NASA made the discovery while using the Shallow Radar (SHARAD) instrument on the Orbiter, which revealed long, continuous layers stretching up to 600 miles, or about one-fifth the length of the United States. The radar pictures show a smooth, flat border between the ice cap and the rocky Martian crust, NASA said. On Earth, the weight of a similar stack of ice would cause the planet's surface to sag. The fact that the Martian surface is not bending means that its strong outer shell, or lithosphere, a combination of its crust and upper mantle, must be very thick and cold."
I compiled the first in situ measurements of the annual temp and pressure cylces on mars (viking lander).
I was always surprised by the mars has water debate when it seemed to me the vapor pressure of the atmosphere was less than the vappor pressure of water.
Thus to my mind if mars had water in any abbundance then it had to be bound up in some mixture that was lowering the vapor pressure.
Apparently there may be another possibility: deep very cold storage.
But either way: no available surface water. No canals. no oceans.
Some drink at the fountain of knowledge. Others just gargle.
A very interesting read is "Is Mars Habitable?" by Alfred Russel Wallace. Written in 1907 it refutes the then current notion put forward by the astronomer Percival Lowell that Mars had canals, flowing water and plant life.
Undetectable Steganography? Yep, there's an app fo
This was already suspected. The giant volcanic pile of Tharis fails to cause significant flexure of the lithosphere. This has been known since the Viking days. On earth 14000' feet (the height of Mona Loa) is about how much you can load oceanic crust on earth without causing it to sag. On Mars no such sagging occurs, and Olympus Mons is nearly 90000' above the planetary mean! This has been known since the Viking days. The polar observations add another data point, but the result is not a surprise.
an ill wind that blows no good
The simple fact is that, even on its' surface (pun intended), it's an obviously wrong comparison. The fact that an ice sheet that size would bend the earths' crust is, as I pointed out, irrelevent - the same mass only weights half as much on Mars. Even more irrelevant because the earths' crust is floating, so more weight would cause a plate to sink slightly, like getting into a rowboat - Mars has no plate tectonics.
> If there are not subterranean aquifers close enough to the surface to be accessible, then things are going to be very hard-going.
I'm not sure where you got the impression that there is no easy to reach water on Mars.
There are billions of cubic kilometers of water ice quite easily accessible at the poles. Furthermore, it's right there on the surface at the north pole (except during winter when it gets covered by a layer of CO2 ice about a meter thick). At the south pole, water ice lies about 8 meters under the CO2 surface ices. (These numbers are very rough estimates, please note.)
If you want water, just apply heat! The problem of gathering and transportation in that environment is non-trivial, but at least there's no shortage of actual water ice.
They're searching for liquid water because that's more likely to harbor life, but for sustaining human life all we have to do is to live near the poles and melt a continuous supply. What we'd need most is a plentiful supply of energy and good isolation from the dangerous environment.
For more info on Martian polar ices, Wikipedia provides a reasonable summary.
"The question of whether machines can think is no more interesting than [] whether submarines can swim" - Dijkstra
By not assuming it's all water ice? Really, how likely is 100% H2O composition anyway?
Seriously, terraforming mars is a project for far future generations. As another poster pointed out inflatable domes should do for the next thousand years. I would probably throw some ice caves into the mix, though - better protection from the stray micrometeorites that still fall in abundance and compressed ice has delightful self-sealing properties. I'm sure the eggheads at NASA that get paid to think about this stuff have even more practical ideas.
From the map some of those cliff faces look like they have stunning views in the summertime.
Help stamp out iliturcy.