Omicron Ursae Majoris

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ο Ursae Majoris
Observation data
Epoch J2000.0
Constellation
(pronunciation)
Ursa Major
Right ascension 08h 30m 15.9s
Declination +60° 43' 05"
Apparent magnitude (V) +3.35
Distance 184 ± 7 ly
(56 ± 2 pc)
Spectral type G5III
Other designations
Muscida, 1 Ursae Majoris,
HR 3323, HD 71369,
BD+61 1054, FK5 317,
HIP 41704, SAO 14573,
GC 11593, ADS 6830,
CCDM 08303+6043

Omicron Ursae Majoris (ο UMa / ο Ursae Majoris) is a star system in the constellation Ursa Major. It is approximately 184 light years from Earth. It also has the traditional name Muscida, which it shares with the optical double star Pi Ursae Majoris.

The primary component, Omicron Ursae Majoris A, is a yellow G-type giant with an apparent magnitude of +3.35. It has a 15th magnitude companion, Omicron Ursae Majoris B, which is 7 arcseconds from the primary. It is sometimes listed with two more companions, Omicron Ursae Majoris C and D but, based on proper motion data, these appear to be optical companions.

The star is also a variable star of unknown type with a period of 358 days and an amplitude of 0.5 magnitude.