Astronomers have for the first time observed a nova-producing system turn into a supernova, a finding that indicates the universe has more than one way to create a nova. A normal Type Ia supernova is a rare event, occurring perhaps once or twice every century. The type of supernova observed by a team of astronomers led by astronomer Ben Dilday of UC Santa Barbara is estimated to occur about one time in every 1,000 supernovae. The findings are important because supernovae are generally all considered to have the same intrinsic brightness, making them what astronomers call “standard candles” used for estimating distances across the cosmos. If some supernovae have different brightnesses because they have a different origin, that could lead to errors in distance measurements.