Water hiding 1.6km below Mars' south pole will be hard to reach. But when we do, we may finally find out if there's life on the planet.

Water hiding 1.6km below Mars' south pole will be hard to reach. But when we do, we may finally find out if there's life on the planet.

Water hiding 1.6km below Mars' south pole will be hard to reach. But when we do, we may finally find out if there's life on the planet.