We find that the short length of the gully features implies they did form under conditions similar to those on present-day Mars, with simultaneous freezing and rapid evaporation of nearly pure liquid water.

In the martian case, fluid well above the boiling point (which is a very low temperature at Mars' low atmospheric pressure and air temperature) is suddenly exposed to the atmosphere. The difference between the vapor and ambient pressures relative to the ambient pressure is large, and flash boiling can occur, leading to a violent loss of fluid.

We tested our model using known flow parameters and environmental conditions of perennial saline springs in the Mars analog environment of the Canadian High Arctic.

If liquid water pops out onto Mars' surface, it can create short gullies about 550-yards (500-meters) long. We used a computer to simulate the flow of liquid water within gully channels.

If liquid water pops out onto Mars' surface, it can create short gullies about 550-yards (500-meters) long. We find that the short length of the gully features implies they did form under conditions similar to those on present-day Mars, with simultaneous freezing and rapid evaporation of nearly pure liquid water.

The gullies may be of prime importance for human exploration. They may represent locations of relatively new surface liquid water, which can be accessed by crews drilling on the Red Planet.