Pi Ursae Minoris

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The Bayer designation Pi Ursae Minoris (π UMi, π Ursae Minoris) is shared by two star systems, π¹ Ursae Minoris and π² Ursae Minoris, in the constellation Ursa Minor. They are separated by 0.64° on the sky.

π¹ Ursae Minoris[edit]

π¹ Ursae Minoris
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Ursa Minor
Right ascension 15h 29m 23.77s
Declination +80° 27' 00.3"
Apparent magnitude (V) +6.58
Distance 70.8 ± 1.1 ly
(21.7 ± 0.3 pc)
Spectral type G0IV-V+G8IV-V
Other designations
HR 5829, HD 139777 +HD 139813, BD+80 480 +BD+80 481, HIP 75809 +HIP 75829, SAO 2556 +SAO 2558, GC 20929 +GC 20935, ADS 9696,CCDM 15293+8027

Pi-1 Ursae Minoris is a triple star system approximately 70.8 light years from Earth. The system is dominated by a binary pair of two yellow G-type subgiants which are 32 arcseconds apart and have apparent magnitudes of +6.9 and +7.8. They also have an 11th magnitude companion, Pi-1 Ursae Minoris C, which is 135 arcseconds away.

π² Ursae Minoris[edit]

π² Ursae Minoris
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Ursa Minor
Right ascension 15h 39m 38.72s
Declination +79° 58' 59.2"
Apparent magnitude (V) +6.89
Distance 384 ± 42 ly
(118 ± 13 pc)
Spectral type F2
Other designations
HD 141652, BD+80 487, HIP 76695, SAO 2588, GC 21163, ADS 9769, CCDM 15396+7959

Pi-2 Ursae Minoris is a binary star approximately 384 light years from Earth. The primary component, Pi-2 Ursae Minoris A, is a yellow-white F-type star with an apparent magnitude of +6.89. The companion star, Pi-2 Ursae Minoris B, has an apparent magnitude of +8.3 and is 0.67 arcseconds from the primary. The binary star completes one orbit every 188 years.