Atmospheric losses: D/H
ratios
Think about deuterium (D): 2H
(one proton + one neutron [+ one electron]). So water molecules can
come in two types:
On Mars, D/H ~ 8x (D/H)Earth -- Mars lost water through atmosphere!
How much? D/H is a measure of fractional loss. We also have a measure of how much water vapor is currently in Mars' atmosphere (it's small). These two combined can tell us the total amount of water lost through atmospheric processes, and it's much less than the total amount needed to explain the channel flows.
Where's the rest?
Conditions aren't right for liquid water!
What does this mean?
Jarosite nodules
(greenish-blue)
|
Hematite nodules |