Long before Mars turned into the frozen desert you see today, water shaped its surface in dramatic ways. Rivers cut through highlands, lakes pooled inside craters, and floods tore open canyon walls.

Bright white rocks spotted by NASA’s Perseverance rover are rewriting what we thought we knew about ancient Mars. These ...

Mars, now a dusty world of rusted rock and thin air, once carried enough water to transform its face into something far more familiar. New mapping of ancient river systems indicates that a vast ...

Using images from cameras on Mars orbiters, an international research team has discovered structures on Mars that are very similar to classic river deltas on Earth. These are traces of rivers that ...

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

MARS was not always the beaming red we’re so used to seeing in space. Scientists have revealed that it was actually a “blue ...

Mars may have been a "blue planet" with an ocean the size of today's Arctic Ocean, a new study suggests.

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