These Clues Indicate That Water Once Flowed On Mars

At first glance, it looks as if Earth is the only planet in the solar system that has ever sported vast liquid oceans. On the other hand, planetary scientists think that Mars had flowing water of its own at one point in the past.

Various clues support this theory, including the presence of gray-colored hematite in the red planet's plains, multiple sites of multi-layered rock that looks as if flowing water carved it out, and signs of chlorine and bromine residing in the rocks.

Many of these discoveries wouldn't have been possible without NASA's Opportunity and Curiosity rovers, but exploration won't end there. The space agency's upcoming Mars 2020 rover is nearing completion and will soon pick up exploring where its predecessors left off.

It should be interesting to see whether Mars 2020 validates these findings or if it discovers new ones entirely.