Wet Mars : Credits: NASA/GSFC
The journal Nature Communications has published a paper detailing research into comparatively recent water flow on Mars.
“Liquid water is currently extremely rare on Mars, but was more abundant during periods of high obliquity in the last few millions of years. This is testified by the widespread occurrence of mid-latitude gullies: small catchment-fan systems. However, there are no direct estimates of the amount and frequency of liquid water generation during these periods. Here we determine debris-flow size, frequency and associated water volumes in Istok crater, and show that debris flows occurred at Earth-like frequencies during high-obliquity periods in the last million years on Mars. Results further imply that local accumulations of snow/ice within gullies were much more voluminous than currently predicted; melting must have yielded centimetres of liquid water in catchments; and recent aqueous activity in some mid-latitude craters was much more frequent than previously anticipated.”
The complete paper, which postulates that periodic changes in the Red Planet’s inclination towards the sun lead to periods of increased sublimation of polar ice which then makes its way into the mid latitudes as water vapor is here, and an LA times article on the subject is here.
Note: While very interesting, it is difficult to say that this research comes as much of a surprise. Evidence has been mounting in recent years which builds the case for a planet which still contains quite a bit of water. Indeed some images taken by the Mars Reconnaissance Orbiter’s Hi-Rise camera seem to have captured liquid outflows on steep canyon walls which were not seen on previous passes of the same area. Alas. with the current program of very cautious rover based research which cannot reach difficult terrain where all the action seems to be, we are left guessing.
Leaving aside the issue of which launch system should get us there, this is a problem tailor made for those who advocate for an orbit first architecture featuring tele-robotic operation of ground and aerial assets from a unique vantage point with low latency.