What is this? (Paint related)

Well its fixable and I still have over a half gallon left. I think this time around ill get some help. Thanks for the replies fellas. I have a good Idea what I need to do. But I want a quality finish so I guess i need to get to it. Can I get some discs in 600 grit and use the RO Sander?

Hand sand it with a good flat block if I were you! Orbitals will more than likely remove to much material too fast! Using tools will more than likely screw your bodywork up too.