Supernova 1987A.

The circumstances of SN 1987A are nearly ideal for studying supernovae and we have a relatively complete observational record. The Large Magellanic Cloud is fortuitously well placed in the sky, circumpolar for recently constructed southern observatories and near the ecliptic pole. These practical advantages, a rich and varied set of observations can be used to test a well-developed, but hitherto poorly calibrated, theory for supernova explosions. This review cannot explore every aspect of SN 1987A. The authors have tried to emphasize the main event: the test of stellar evolution represented by the observations.