Indeed, the server is currently down due to technical issues. You can read more here:

http://community.playstarbound.com/index.php?threads/server-wont-start.67361/

I could wipe out the server and rebuild, but we'd lose everything we built. I could save the Universe folder, but it's possible the issue is in that folder. So expect the server to be down for a bit as this is worked on.

Thank you for your understanding.