Mulling Martians Elon Musk's plans to become "multiplanetary" grow more ambitious every year — but it's unclear whether he'll live long enough to actually see it happen. As the Wall Street Journal reports,

A representative for SpaceX didn't respond to a request for comment.

NASA rotates space station crews approximately every six months, so this flight with two empty seats reserved for Wilmore and Williams won’t return until next year.