Skip to main content

Special Notice #241: New Supernova in M51

June 3, 2010: A new supernova in M51 was discovered by A. Riou and confirmed by several sources, including the Palomar Transient Factory (Silverman et al., ATEL 3398). It is located at 13:30:05.08 +47:10:11.2 J2000 and has a magnitude of about 13.5. Nice images of the supernova can be found at: PTF also obtained a spectra from Keck, indicating that this is a type II supernova with a relatively blue continuum with P-Cygni profiles in the Balmer series. This is a unique event, because it occurs in a galaxy that is imaged almost constantly. There must be many photos available that show the rise of this SNe, so the data-mining opportunity is obvious. It is transiting at local twilight and should be observable for northern hemisphere observers for several months. A new APASS sequence should be uploaded soon. We recommend taking nightly monitoring images in B and V for CCD observers, along with visual estimates, until the supernova is no longer visible. Here is an excuse to take the 10 millionth image of M51!
Arne A. Henden

AAVSO 49 Bay State Rd. Cambridge, MA 02138 617-354-0484