Messier 106, also known as NGC 4258, is one of the most brilliant nearby galaxies, located in the constellation Canes Venatici some 20 to 25 million light years from Earth. It rivals the Andromeda galaxy in size and is a familiar target for amateur astronomers. Discovered in 1781 by Charles Messier’s assistant, Pierre Méchain, M106 was not originally included in Messier’s famous catalogue. The galaxy and six other objects the pair discovered were added to the catalogue in the 20th century. This image combines observations by the Hubble Space Telescope with additional data from amateur astronomers Robert Gendler and Jay GaBany.
The image below, also from the Hubble Space Telescope, includes the glow of ultraviolet radiation.