V598 Puppis is the name given to a nova in the Milky Way Galaxy. USNO-A2.0 0450-03360039, the catalog number for the star, was discovered to be much brighter than normal in X-ray emissions on October 9, 2007, by the European Space Agency's XMM-Newton telescope. Ultimately, the star was confirmed to 600 times brighter than normal by the Magellan-Clay telescope Magellan-Clay telescope at Las Campanas Observatory in Chile.
The nova has been officially named V598 Puppis and is "one of the brightest for almost a decade". Despite its brightness, the nova was apparently missed by amateur and professional astronomers alike until XMM-Newton spotted the unusual X-ray source while turning from one target to another. The All Sky Automated Survey determined that that nova had occurred on June 5, 2007.