Messier 106 (M106), also known as NGC 4258, is a stunning spiral galaxy located in the constellation Canes Venatici, about 23.7–25 million light-years from Earth. It was discovered by Pierre Méchain in 1781 and is one of the largest and brightest nearby galaxies, comparable in size and luminosity to the Andromeda Galaxy.

Notable Features:

• Supermassive Black Hole: M106 has an active nucleus, classified as a Type 2 Seyfert galaxy, meaning it harbors a supermassive black hole that is actively consuming material.

• Anomalous Arms: Unlike most spiral galaxies, M106 has two extra arms composed of hot gas rather than stars. These ghostly arms are thought to be caused by the violent churning of matter around the black hole.

• Water Vapor Megamaser: M106 contains a water vapor megamaser, a natural laser-like emission in the microwave spectrum, which has helped astronomers measure cosmic distances more accurately.

• Cepheid Variables: The galaxy contains Cepheid variable stars, which have been crucial in calibrating the cosmic distance ladder, improving our understanding of distances in the universe.

• Supernovae: Two supernovae have been observed in M106, including SN 1981K, a Type II supernova.

M106 is a favorite target for astrophotographers, and its bright core and intricate spiral arms make it a breathtaking sight in telescopes.

Learn more

science.nasa.gov | messier-objects.com