Tom Boles, who runs his own observatory and spends his spare time hunting for supernovae, has found another explosion in space. SN 2010gb occurred in the galaxy UGC 9947 at a magnitude of 16.5 and was imaged on the 11th of July. See a picture of UGC 9947 without supernova here (also with coordinates of the galaxy).
Boles has seen many a supernova and finds them by repeatedly scanning areas of the sky and looking for relatively bright blobs that weren’t there before. Now there’s always a chance that these could be other forms of bright blobs varying in brightness – as Mike Simonsen of the American Association of Variable Star Observers notes in this post on a supernova that wasn’t. In order to verify one way or another, spectra and light curves are taken. The spectrum will identify lines characteristic to certain types of explosion and the light curve, a map of brightness with time, will also do the same.
The three elements of supernova or other variable star observations are therefore spotting an appearance or change in brightness of an object, measuring its spectrum and measuring the change in brightness. With a standard camera, you can perform one of these quite obviously – take a picture of the night sky, take another one and repeat ad infinitum. You’re unlikely to get a supernova that way unless you fit a telescope to the camera, but you’ll get a few variables, asteroids and the like. For a deeper investigation, you might want to investigate the change in brightness, standard DSLRs can also do this – as this post at the British Astronomical Association‘s blog explains.