New Hydrogen Clouds in M81 Cluster

A composite radio-optical image shows five new clouds of hydrogen gas discovered using the Green Bank Telescope. The spiral galaxy M81 and its satellite, M82, are seen in visible light (white); the new hydrogen gas is colored red; and additional hydrogen gas earlier detected by the Very Large Array (green). The M81 Group of galaxies, 11.8 million light-years from Earth, are interacting gravitationally with each other, as shown clearly by the gas streaming among them. The newly-discovered gas clouds, each containing from 14 to 57 million times the mass of our Sun, are similar to gas clouds near our own Milky Way Galaxy. They are likely remnants of earlier interactions among the galaxies. Probably, the Milky Way has had a similar history.