SN 2004dj

SN 2004dj was the brightest supernova since SN 1987A at the time of its discovery.

SN 2004dj

Other designations	SN 2004dj, CXOU J073717.1+653557, CXO J073717.0+653557
Event type	Supernova, high mass X-ray binary
Spectral class	II-P
Date	31 July 2004 18:15 UTC
Constellation	Camelopardalis
Right ascension	07h 37m 17.044s
Declination	+65° 35′ 57.84″
Epoch	J2000.0
Galactic coordinates	?
Distance	about 11,000,000 light-years
Remnant	Nebula
Host	NGC 2403
Progenitor	Unknown star in compact cluster Sandage 96
Progenitor type	Supergiant
Colour (B-V)	Unknown
Notable features	Light Curves
Peak apparent magnitude	+11.2
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This Type II-P supernova was discovered by Koichi Itagaki, a Japanese astronomer on July 31, 2004. At the time of its discovery, its apparent brightness was 11.2 visual magnitude; the discovery occurred after the supernova had reached its peak magnitude. The supernova's progenitor is a star in a young, compact star cluster in the galaxy NGC 2403, in Camelopardalis. The cluster had been cataloged as the 96th object in a list of luminous stars and clusters by Allan Sandage in 1984; the progenitor is therefore commonly referred to as Sandage 96. This cluster is easily visible in a Kitt Peak National Observatory image and appears starlike.