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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."
All in all, bad news for people who hoped that Kim Stanley Robinson's trilogy beginning with Red Mars would be a reasonable vision of the settlement and terraformation of Mars. If there are not subterranean aquifers close enough to the surface to be accessible, then things are going to be very hard-going.
Rock can compress. I imagine that the effect is relatively easily observed when you are considering the compression over several miles of thickness. The article says little to nothing about what exactly they observed, so it's hard to say if the comparison is obviously wrong or not.
Nerd rage is the funniest rage.
According to the article the ice cap on mars is in four layers each a 1/4 mile thick roughly. These layers each represent a million year period of deposition.
It follows that either there was liquid water and water vapor on mars to deposit the ice at the pole, or there was a horde of very determined martians with trucks to move it there :). I would go with the canals and oceans theory myself.
So we have roughly a cylinder of ice a mile thick and a thousand miles across on Mars. With the careful application of energy that's more than enough to produce a breathable atmosphere or at least provide for a considerable human habitat.
I am less concerned about finding life on mars than I am with putting it there. We can leave to the exploration of the asteroid belt the discovery that mere interplanetary distances are not an effective barrier to lichens, let alone intelligent life. Besides, the best evidence for fossil life on mars will be found in the Basal Unit under that mile thick ice. That's a lot of digging for a girl in a space suit.
Help stamp out iliturcy.
Or perhaps subterranean oceans, canals. Why do we expect life to develop on or near the surface again?
I was also involved in Viking. At that time, we did not know about the long term (30Kyr and longer) cycles in the Martian obliquity and solar insolation. During the cycle the polar regions lose and gain material - the layering at the poles is clear evidence of that.
Mars, as you point out, is at present very close to the triple point of water, but it is below it (so no liquid water). However, at other times in its dynamical cycle, surface conditions are almost certainly above the triple point, as water and CO2 are lost by the poles and put into the atmosphere. So, it seems pretty clear that Mars goes through wet and dry cycles, although the further implications of that are very much a matter of debate.