The irregular filaments and patchy structures seen in M82ΓÇÖs H alpha emission are quite different from the pattern seen in visible light. The brightest H alpha emission in galaxies emanates from regions where new stars are forming; the starsΓÇÖ intense illumination heats the surrounding gas. Because of M82ΓÇÖs strong emission, astronomers believe that stars are forming in its nucleus at a prodigious rate.
M82ΓÇÖs H alpha emission is concentrated toward its center but also extends about 10,000 light years above and below the plane of the galaxy. The filamentlike structures look very similar to H alpha structures seen around the Crab Nebula, which is a gaseous remnant of a giant supernova explosion that occurred in our own