SN 2005bc

SN 2005bc was a Type Ia supernova^[3] occurring in the barred spiral galaxy NGC 5698,^[1] located in the northern constellation of Boötes. SN 2005bc was discovered on 2 April 2005 by LOSS and independently by Tim Puckett and L. Cox.^[4] It was positioned at an offset of 4.6″ east and 7.5″ north of the galactic nucleus.^[1] The supernova was at magnitude 16.4 at discovery, and quickly rose to a peak magnitude of around 15.3 (in visible light) just over a week after discovery. It showed an expansion velocity of 12,000 km/s.^[3] By mid-May, the supernova had faded to 17th magnitude.

SN 2005bc

SN 2005bc just over a week after peak brightness
Event type	Supernova
Type Ia[1]
Date	c. 129.3 million years ago (detected 2 April 2005 by Tim Puckett and L. Cox[1])
Constellation	Boötes
Right ascension	14h 37m 14.78s[1]
Declination	+38° 27′ 23.1″[1]
Epoch	J2000.0
Galactic coordinates	Long 66.76° Lat 65.17°
Distance	129.3 Mly (39.63 Mpc)[2]
Redshift	0.0132, 0.0122
Host	NGC 5698[1]
Progenitor type	white dwarf
Peak apparent magnitude	+16.6[1]
Other designations	SN 2005bc

The host galaxy, NGC 5698, along with the supernova lie approximately 129 million light-years (~40 million parsecs) from Earth.^[2] As the supernova was of Type Ia, its progenitor star was a compact white dwarf star that exceeded the Chandrasekhar limit.