For years, scientists have been intrigued by mysterious dark streaks running down the slopes of Martian cliffs and craters. These marks, called slope streaks and recurring slope lineae (RSLs), have ...

"The structures that we were able to identify in the images are clearly the mouth of a river into an ocean." The post ...

Scientists have traced ancient Martian shorelines inside a giant canyon, revealing where a vast ocean once stood and why ...

Mars today is a frozen, dusty desert. But if you look deep inside Valles Marineris, the largest canyon system on Mars and in ...

Mars is absolutely dripping with evidence that the red planet was once a striking blue, complete with glistening lakes, ...

For years, scientists have been looking for signs of liquid water just beneath the surface of Mars. The problem, though, is that the observations from various orbiting probes have been maddeningly ...

A study by scientists at Penn State and NASA shows that intact biomolecules from dormant microbes break down much more slowly ...

Until recently, Mars was studied only through telescopes and some data that was recorded from early spacecraft. It was thought that Mars' polar regions were the only significant reservoirs of ice, ...