India’s attempt to land a rover on the moon appears to have ended in failure. The Indian space agency lost contact with the lander during a touchdown attempt earlier this month. It follows the landing failure of another mission — SpaceIL’s attempt to land the Beresheet spacecraft on the moon earlier this year.

So what makes these lunar missions so hard?

The two recent failures highlight just how difficult lunar missions can be. Joining us to talk about the engineering challenges of such a mission is Dan Batcheldor — head of aerospace, physics and space sciences at Florida Tech.

And, we’re asking our expert panel of scientists about gravity waves — what are they and how are they helping scientists better understand the universe. UCF planetary scientists and hosts of the podcast Walkabout the Galaxy Addie Dove, Jim Cooney and Josh Colwell unpack the mysteries of gravity waves.