SIMBAD references

Stuart Parker, Oxford, Canterbury, New Zealand, reports his discovery of an apparent supernova (red mag 18.0) on a 30-s unfiltered CCD image (limiting mag 19.5) taken with a 35-cm Celestron C14 reflector (+ ST10 camera) at his Parkdale Observatory on Nov. 13.57 UT in the course his participation with the Backyard Observatory Supernova Search. The new object is located at R.A. = 5:22:41.50, Decl. = -39:03:44.3 (equinox 2000.0), which is 11" west and 5" north of the center of nucleus of the galaxy ESO 305-21. Nothing is visible at this position on Digitized Sky Survey red and infrared plates (limiting red mag > 19). The variable was designated PSN J05224150-3903443 when it was posted at the Central Bureau's TOCP webpage and is here designated SN 2012gk based on the spectroscopic confirmation reported below. Additional unfiltered CCD magnitudes for 2012gk: Oct. 22.679, [18.5 (Parker); Nov. 4.582, 17.9 (Parker; apparent pre-discovery image; limiting mag 18.5); 15.60, 18.0 (Greg Bock, Windaroo Lakes Observatory, Queensland, Australia; Meade 350F7 ACF telescope + ST10XE camera; limiting mag > 19.0).