부산대학교 도서관

Dry run for a supernova When a bright optical transient was discovered in galaxy UGC 4904 in October 2004 the signs were that it was big enough and bright enough to be a supernova. Further work suggested that it was not quite on that scale; but almost exactly two years after its discovery it seems to have exploded in a big way. Supernova SN 2006jc is in exactly the same place in the sky as the earlier optical transient. This is the first time that such a double outburst has been observed. One possibility is that the initial transient was an outburst from a Wolf-Rayet star, a very hot massive star losing mass rapidly. Or the system might be a binary containing a luminous blue variable star that erupted in 2004, followed two years later by a companion Wolf-Rayet star exploding as SN 2006jc.