Messier 90 — Galaxy in Virgo

M90 is a large spiral galaxy located about 60 million light-years away in the constellation Virgo, within the Virgo Cluster. It is one of the largest and brightest spirals in the cluster, spanning roughly 165,000 light-years across — larger than the Milky Way. Like M86, M90 is one of the rare Messier galaxies that is blueshifted, meaning it is approaching us rather than receding. This is because M90 is moving through the Virgo Cluster at high velocity and happens to be on a trajectory toward the Milky Way. The galaxy is classified as a weakly barred spiral (type SAB) with well-developed, smooth spiral arms that show relatively little active star formation compared to other spirals, suggesting it may be transitioning toward an anemic or passive spiral state.

Located about 1.5 degrees north-northeast of M87 in the Virgo Cluster core. A 4-inch telescope at 80-100x shows an elongated, oval glow with a bright central region. M90 is one of the larger and brighter Virgo Cluster galaxies, making it a rewarding target. An 8-inch telescope reveals more of the extended disk and the contrast between the bright nucleus and the diffuse outer regions. Under excellent dark skies, hints of spiral arm structure may be glimpsed with larger apertures (12 inches+). Look for the nearby galaxies M89 and M58 to complete a triangle of bright Virgo galaxies. Best observed from March through June.

Discovered by Charles Messier on March 18, 1781, during the same session that yielded many Virgo Cluster galaxies for his catalog. M90's blueshift was measured spectroscopically in the early 20th century, making it one of the first galaxies found to be approaching our own. Modern studies suggest M90 may eventually escape the Virgo Cluster entirely, becoming an isolated field galaxy.