APOD: 2022 April 23 - Messier 104

Good afternoon, Rallypoint, and welcome to the April 23rd Astronomy Picture of the Day (APOD): "Messier 104." Also known as the Sombrero Galaxy, M104 is the first numerical object not included in Messier's original catalog. He (Messier) added it by hand to his personal copy on May 11, 1781, and described it as a "very faint nebula." Camille Flammarion, who found and acquired Messier's personal copy and notes of the Messier Catalog from an old book store, determined that Herschel's H I.43 (observed independently on May 9th, 1784) and the Sombrero Galaxy were one in the same. Flammarion added it to the official Messier list in 1921.

There have been multiple studies of M104 in infrared, x-ray, and visible light. I'll post in a separate comment an APOD from 2007 that highlights this work.