Messier 65 — Galaxy in Leo

M65 (NGC 3623) is a spiral galaxy in the constellation Leo, located approximately 35 million light-years from Earth. It is classified as type SAB(rs)a, an intermediate spiral with tightly wound arms. At magnitude 9.3, it spans about 8.7 by 2.5 arcminutes, corresponding to a true diameter of roughly 90,000 light-years. M65 is one of three prominent galaxies forming the Leo Triplet (along with M66 and NGC 3628), one of the most celebrated galaxy groups in the sky. The galaxy is seen at a fairly high inclination of about 65 degrees, presenting an elongated profile with a prominent dust lane running along its near edge. M65 has a well-defined central bulge and relatively smooth, tightly wound spiral arms with less star formation activity compared to its neighbor M66. The galaxy's disk appears remarkably undisturbed despite its proximity to the other Leo Triplet members, suggesting that gravitational interactions have been relatively mild on this side. M65 contains a mixture of old and intermediate-age stellar populations, with the bulge dominated by older yellow-orange stars.

Located beneath the hindquarters of Leo, about 2.5 degrees south-southeast of Chertan (Theta Leonis). M65 and M66 are visible together in the same low-power eyepiece field, making them a popular galaxy pair for observers. NGC 3628 lies about 35 arcminutes to the north, completing the Leo Triplet. In binoculars, M65 appears as a faint elongated smudge. A 4-inch telescope at 80-100x reveals a spindle-shaped glow with a brighter center. An 8-inch telescope shows the galaxy's dust lane as a subtle darkening along one edge. With 10-12 inches under dark skies, the dust lane becomes more distinct and the elongated disk extends further. Best observed from February through May when Leo is high.

Discovered by Charles Messier on March 1, 1780, on the same night he cataloged M66. William Herschel later observed both galaxies and noted their close proximity. The Leo Triplet has become one of the most photographed galaxy groups, with deep images revealing a spectacular tidal tail extending from NGC 3628 due to gravitational interactions within the group.