A supernova in spiral galaxy M66, part of the Leo Trio of galaxies. Discovered on May 28th at magnitude 16.7, this is still very faint (estimated by me at 16.9 off the DSLR images). Imaged at 13h UT on 29th May.
12 x 5 minutes, EOS 60D at ISO800 on HEQ5Pro. 200mm f/5 Newtonian. Darks, flats and bias subtracted. Processed in PixInsight.