Apparently in the current Unstable, if you delete a character and start a new one -- you end up on the same planet your first character inhabited. Anyone know a fix to restart as though from scratch?
Delete your universe.dat. The spawn coordinates are generated when that file is created and stored in it. Currently, you can't have characters start on different planets, only reset the starting coordinates to a new planet (which is then used from that point on). Edit: As a side note, if you're running a server (or for some other reason) you should be able to specify the coordinates you want to use in your starbound_server.config (don't forget to change the other setting so they get used).
IT WORKED FOR ME.... Must be user error. (It won't reset the current world for existing characters, only new ones created after generation of a new universe.dat).