M82s

M82s is not a standard astronomical designation. In most contexts the term may refer informally to Messier 82 (M82) itself or to galaxies that resemble M82; there is no formal object routinely cataloged as “M82s.” The prototype object is Messier 82, a nearby starburst galaxy in Ursa Major that is often studied as a representative of intense, interaction-driven star formation.

Messier 82 (M82) lies about 3.5–4 megaparsecs from Earth, roughly 12 million light-years away. It is classified as a starburst galaxy, with the bulk of its star formation concentrated in its central region. The starburst activity is believed to be enhanced by gravitational interactions within the M81 group, which have funneled gas into the core and triggered rapid star formation. M82 is one of the brightest infrared galaxies in the local universe, reflecting the large amount of dust absorbing ultraviolet light from young stars and re-emitting it in the infrared.

The galaxy exhibits a prominent galactic superwind: a bipolar outflow of gas and dust driven by the collective effect of supernovae and stellar winds from the central starburst. This outflow is detectable across multiple wavelengths, including optical emission lines, radio, and X-ray bands, and it plays a key role in transferring material from the galaxy into its halo.

Notable events in M82 include the supernova SN 2014J, discovered in 2014. Observational programs across radio, infrared, optical, and X-ray wavelengths continue to study M82’s starburst processes, its interaction with the M81 group, and the dynamics of its outflow.

In usage, “M82s” may occasionally appear as a plural form or shorthand for M82-like galaxies, but it is not a distinct cataloged class.