* Astronomy

NGC 3992 (also Messier 109, M109, IRAS 11549+5339, MCG 9-20-44 and PGC 37617) is a magnitude +10.6 spiral galaxy located 83.5 ±24 million light-years away in the constellation Ursa Major.
M109 is easy to locate, being visible just 1° to the south-east of the bright star gamma Ursae Majoris (Phecda), part of the 'asterism of the Big Dipper, although it is not visible with 50mm binoculars. M109 is the brightest galaxy in the M109 group, a large group of galaxies located in the constellation Ursa Major, which may also contain more than 50 galaxies. M109 has three satellite galaxies, catalogued as UGC 6923, UGC 6940 and UGC 6969.

The galaxy was discovered by French astronomer Pierre Méchain using a 90 mm (3.5") refractor from the Hotel de Cluny on the 12th March 1781.
The galaxy was rediscovered  by Charles Messier on the 24th March 1781.
M109 was added to the 'official' Messier catalogue in 1953 by Owen Gingerich.

The galaxy hosted supernova 1956a which appeared on the 17th March, 1956, and reached an apparent magnitude of +12.6 at its peak.

Right Ascension 11h 57m 35.4s, Declination +53° 22' 25"

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