What is fuel cost?

I just got my ship in SW: The Old Republic and I noticed that space missions have a fuel cost associated with them.

What does it actually mean? Do I need to buy fuel periodically? Where can I see how much fuel I have?

It's a measure of how far away you are from the location on the galaxy map (measured from whichever planet or station you're currently orbiting from).

It's a pretty negligible cost over-all, but if you want to run one space mission repeatedly, you can move to a nearby system to reduce the fuel cost each time.

It's the same principle that costs you credits in fuel whenever you fly from planet to planet.