Astronomers watch the stars come out in berkeley.

New and strange sightings caught the attention of astronomers at this June's American Astronomical Society (AAS) meeting in Berkeley: a supernova that has changed its identity, a clutch of mysterious blue stars, and objects at the edge of the universe, shining brilliantly at the far end of the ultraviolet spectrum. Meanwhile, a more familiar object-one species of supernova-is raising hopes of predicting the ultimate fate of this cosmic zoo.