I learned two things from Elon Musk’s appearance on The Late Show last night: Even billionaires get tongue-tied on national TV, and Earth is out, Mars is in.

In addition to talking about a creepy-looking prototype for Tesla’s at-home charging system, Musk told host Stephen Colbert that while Mars maybe be a tad inhospitable now, it’ll be fine (just fine!) after we (he) transform(s) it into an “Earth-like planet.” And how are we (is he) going to do that? Drop a few nukes over the poles, of course. Cool! Or Musk could use his considerable power to help keep the Earth we have “Earth-like” enough so we could continue to survive on it. It’s not quite as exciting as colonizing a new planet but, hey, it’s good to have a back-up plan in case this Mars thing doesn’t work out.