Well, uh... we'd have to have an idea of where we started on the planet first. And do we even know what direction we're driving in?

[Besides, Apollo has never been on a road trip before this one. He has no idea how long it would take to drive through an entire hemisphere - and wouldn't it depend on the size of the planet, too?]

I think any star charts would stay useful for quite a while. If we were on Earth, you could navigate in a couple of ways - it's either following the northern or southern pole stars, or watching to see if the stars are moving with you or against you as the planet turns.