The Leo Triplet (also known as the M66 Group) is a small group of galaxies about 35 million light-years away in the constellation Leo. This galaxy group consists of the spiral galaxies M65, M66, and NGC 3628.
M65 was discovered by Charles Messier and included in his Messier Objects list. However, William Henry Smyth accidentally attributed the discovery to Pierre Méchain in his popular 19th century astronomical work A Cycle of Celestial Objects (stating "They [M65 and M66] were pointed out by Méchain to Messier in 1780"). This error was in turn picked up by Kenneth Glyn Jones in Messier's Nebulae and Star Clusters. This has since ramified into a number of other books by a variety of authors.
Messier 66 (also known as NGC 3627) is an intermediate spiral galaxy. It was discovered by Charles Messier in 1780. M66 is about 95 thousand light-years across with striking dust lanes and bright star clusters along sweeping spiral arms.
NGC 3628, also known as the Hamburger Galaxy or Sarah's Galaxy is an unbarred spiral galaxy. It was discovered by William Herschel in 1784. It has an approximately 300,000 light-years long tidal tail. Its most conspicuous feature is the broad and obscuring band of dust located along the outer edge of its spiral arms, effectively transecting the galaxy to our view.
Equipment and processing
Telescope: Orion 8" F5
Mount: Orion Atlas
Camera: ST 8300M
Filters: Baader Ha,SII,OIII 7nm
Capture software: Maxim
Exposures: L: Bin1 80x300, RGB: Bin2 40x300