English: A new supernova was reported in the Whirlpool Galaxy (M51) by German amateur astronomer Wolfgang Kloehr on June 28. The discovery was confirmed on June 30 by the Katzman Automatic Imaging Telescope at Lick Observatory, which found it to be shining at a magnitude of 13.5; the supernova was reported to the astronomical community by IAU Circular 8553 and given the designation SN 2005 CS.

Eighteen teachers from the Teacher Leaders in Research Based Science Education (TLRBSE) program conducted by the National Optical Astronomy Observatory (NOAO) in Tucson, AZ, happened to be on Kitt Peak for five nights, as part of the program’s fifth annual two-week summer workshop. In the process of learning how to take telescope images in multiple colors at the WIYN 0.9-meter telescope on June 30, the TLRBSE teachers selected M51 as a target and took images of the galaxy in four filters.

After realizing that they had imaged a supernova, TLRBSE teachers made further images of M51 using the WIYN 0.9-meter (and obtained spectroscopic data with the Kitt Peak 2.1-meter telescope), producing the image above (marked with the location of the new supernova).