Messier 81

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**Messier 81**
Observation data (Epoch J2000)
Galaxy	List of galaxies
Image:Bode'sGalaxy.jpg M81
Constellation	Ursa Major
Right ascension	09^h 55^m 33.2^s<ref name="ned" />
Declination	+69° 3′ 55″<ref name="ned" />
Redshift	-34 ± 4 km/s<ref name="ned" />
Distance	11.8 ± 1.1 Mly (3.6 ± 0.3 Mpc)<ref name="Karachentsevetal2006">Karachentsev, I. D.; Kashibadze, O. G. (2006). "Masses of the local group and of the M81 group estimated from distortions in the local velocity field". Astrophysics 49 (1): 3-18.</ref>
Type	SA(s)ab<ref name="ned">NASA/IPAC Extragalactic Database. Results for NGC 3031. Retrieved on 2006-11-10.</ref>
Apparent dimensions (V)	26′.9 × 14′.1<ref name="ned" />
Apparent magnitude (V)	+7.9<ref name="ned" />
Notable features
Other designations
NGC 3031,<ref name="ned" /> UGC 5318,<ref name="ned" /> PGC 28630,<ref name="ned" /> Bode's Galaxy<ref name="simbad">SIMBAD Astronomical Database. Results for NGC 3031. Retrieved on 2006-11-10.</ref>

Messier 81 (also known as NGC 3031 or Bode's Galaxy) is a spiral galaxy about 12 million light-years away in the constellation Ursa Major. It was first discovered by Johann Elert Bode in 1774 and was nicknamed Bode's Galaxy in his honour. In 1993, a supernova (SN 1993J) of was observed in M81.

M81 is believed to contain approximately 250 billion stars, making it slightly smaller than our own Milky Way Galaxy. It is one of the most striking examples of a grand design spiral galaxy, with near perfect arms spiraling into the very center.

M81 and M82 are the most prominent members of the M81 Group with M81 being about twice as massive as M82 which is estimated to be only 54%<ref name="Karachentsevetal2006" /> of the mass of M81.

M81 has an apparent magnitude of +7.9, making it one of the brightest galaxies that can be seen from the Earth. While compact objects of such magnitudes are visible to the naked eye under ideal conditions [1], the diffuse nature of M81 renders it too faint to see unaided, and thus cannot claim the title for furthest naked-eye object (which is usually taken to be M33)