Let's turn to Mars, where it's drier than the San Fernando Valley during August. Scientists have yet to discover any standing water on the surface of the red planet, but that doesn't mean that it wasn't there in the distant past.
For a while now, scientists have assumed that it's likely that there were once rivers and lakes on the surface of Mars. Now new research from Caltech has added credence to the idea that there could have been a huge martian ocean as well.
Credit: DiBiase et al./Journal of Geophysical Research/2013 and USGS/NASA Landsat
Martian spring break anyone? Here to talk about the study is Roman DiBiase, a Cal Tech postdoc scholar who worked on the project.