Mars may have once possessed an ocean at least as large as Earth's Arctic Ocean, a new study suggests. Previous research ...

Using images from cameras on Mars orbiters, an international research team has discovered structures on Mars that are very ...

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

New research suggests Mars was once a blue planet, as scientists identify river deltas and signs of a vast ancient ocean on ...

The findings potentially solve the paradox of how liquid water seems to have persisted on Mars even when the climate grew too ...

Thin, seasonal ice may have protected ancient lakes on Mars, allowing liquid water to last for decades despite cold ...

Mars once had sprawling river systems that rivaled major watersheds on Earth, and scientists have now identified the biggest ones for the first time. Researchers mapped 16 massive drainage basins ...

New research has mapped 16 extensive, interlaced river systems on Mars, dating back approximately 3.7 billion years to the Early Hesperian Period. These large river systems, despite covering only ...

A 3.5-billion-year old rock discovered on the Red Planet is "the closest we've come to discovering ancient life on Mars," according to NASA. Potential signs of microbial life were found in a rock ...

A long time ago, life left microscopic signatures on Mars — or did it? That's the question NASA scientists have worked for years to answer. On Wednesday, NASA researchers said the answer might be in a ...