The Chinese rover spent a year bumping around Mars, using ground-penetrating radar to figure out what's going on below the Red Planet's current day surface.

New findings provide evidence that Mars may have had a vast ocean around 3.5 to 4 billion years ago. During this period, the planet had a thicker atmosphere and a warmer climate, creating conditions far more hospitable than the cold and arid landscape we see today.

The ocean - known as Deuteronilus - would have existed roughly 3.5 to four billion years ago, a time when Mars had a thicker atmosphere and warmer climate, according to scientists.