
Mars and Earth riverbeds in comparison (Image: NASA).

A landscape of Mars captured by Pathfinder in 1997 (Image: NASA).
Mars is the fourth planet from our Sun and is believed to be about 10.7% the mass of Earth and approximately half of its size. It is currently thought that sustainable life on Mars may be possible and might have existed there a long time ago, if Earth and Mars share similar planetary histories. We know that they both have polar ice caps, an atmosphere, and exceptional terrain features. With several vehicles set to test for habitability on Mars in the future, humans will be able to properly assess whether a manned mission to Mars prevails as a safe and advantageous exploration plan.