Dashing hopes of potential habitable environments?
Mars’s gullies may be formed by dry ice processes rather than flowing liquid water, as previously thought. This is the conclusion of a study conducted by two French scientists published online on December 21st in Nature Geoscience. They show that, during late winter and spring, underneath the seasonal CO2 ice layer heated by the sun, intense gas fluxes can destabilize the regolith material and induce gas-lubricated debris flows which look like water-sculpted gullies on Earth.
The model created by the two French scientists can also explain why Mars’s gullies are located mostly in the 30̊-60̊ latitude range -with a few spots at higher latitudes- and why most gullies are found on poleward facing slopes between 30̊ and 45̊ latitude. The CO2 induced pressurization and fluidization is predicted to occur precisely where gullies are observed.
All these findings suggest that the solar heating of the seasonal dry ice deposited in winter on Martian slopes is at the origin of a fraction — and possibly all- of the gullies observed on planet Mars. This process has no terrestrial analogues and do not require liquid water. According to this study, the gullies area may not provide potential habitable environments in Mars’s recent past. More.
See also: Don’t let Mars fool you. Those exoplanets teem with life!
Follow UD News at Twitter!