This is a bright supernova in the barred spiral galaxy IC 4830. It was discovered by R. Chassagne at Reunion Island on 24 May 2001 at m=15. It was probably caught just after maximum.
 
Optical finding chart. This is a V image from the CTIO 1.5m telescope at f/13, taken on 26.3 May 2001. We want to position the telescope between the SN and Star 1.

Color picture of SN2001bt. This is a true color picture of SN2001bt made by combining the BVR data. The data were taken on 26.3 May 2001 at the CTIO 1.5m telescope. The colors are sort of washed out because I had to use the "R" filter instead of the "I" filter for the red channel. I also did not have time to do a really good geometric distortion map. The SN is at about 5 o'clock relative to the nucleus of the galaxy and is just at the visible edge of the galaxy. It is not very blue which means it is either not before maximum light, or there is reddening. The Schlegal reddening is E(B-V)=0.065.