Elon Musk has engineered a next-generation rocket and built an electric car empire. But on the Late Show last night Musk seemed very human, nervously chuckling as Stephen Colbert lobbed questions at him.

Nerves aside, Musk made an interesting guest for Colbert’s second-ever Late Show—once Colbert got the requisite super-villain joke (to which Musk did not seem to have a good response) out of the way and got down to real talk: How are we going to warm up Mars to support biological life? Musk nonchalantly says there’s an easy way and a hard way. The easy way? Nuke it. The hard way? Greenhouse gasses.


Musk did have a couple of his own jokes, though. When Stephen showed a clip of Tesla’s creepy prototype recharging robot, asking “is that thing gonna attack me in my sleep?,” Musk quipped in return: “For the prototype, I’d recommend not dropping anything while you’re near it.”

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