STILL MORE EVIDENCE that Mars was once warm and wet:

“Imagine more than five times the volume of water in the Great Lakes being released in a single flood, and you’ll have a sense of the scale of this event,” said Ross Irwin, a geologist in the museum’s Center for Earth and Planetary Studies (CEPS) and the paper’s lead author.

How much of that water still remains locked in the martian soil is unclear, but this is certainly a positive sign: at least we know that the water was there at one point.