Messier 81 (NGC 3031 or Bode's Galaxy) is a spiral galaxy about 12 million light-years away in the constellation Ursa Major. M81 is one of the most striking examples of a grand design spiral galaxy, with near perfect arms spiraling into the very center. Because of its proximity to Earth, its large size, and its active galactic nucleus (which harbors a supermassive black hole) Messier 81 is a popular galaxy to study in professional astronomy research. The galaxy's large size and relatively low apparent magnitude (lower magnitude implies higher brightness) also make it a popular target for amateur astronomy observations.
Messier 82 (NGC 3034 or the Cigar Galaxy) is the prototype nearby starburst galaxy about 12 million light-years away in the constellation Ursa Major. The starburst galaxy is five times as bright as the whole Milky Way and one hundred times as bright as our galaxy's center.
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