Phi Ursae Majoris
  Location of φ Ursae Majoris (circled) | |
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Ursa Major |
| Right ascension | 09h 52m 06.36s |
| Declination | +54° 03' 51.4" |
| Apparent magnitude (V) | +4.55 |
| Characteristics | |
| Spectral type | A3IV |
| Astrometry | |
| Distance | 436 ly (134 pc) |
| Other designations | |
| Database references | |
| SIMBAD | data |
Phi Ursae Majoris (Phi UMa, φ Ursae Majoris, φ UMa) is binary star in constellation of Ursa Major, which is separated in 0.245 arcseconds.[1] Both of components are white A-type subgiant.[2] It is approximately 436 light years from Earth.
Phi Ursae Majoris is moving through the Galaxy at a speed of 21.6 km/s relative to the Sun. Its projected Galactic orbit carries it between 24,000 and 46,000 light years from the center of the Galaxy.[3]
Phi Ursae Majoris will come closest to the Sun 4.7 million years from now when it will brighten to magnitude 3.88 from a distance of 370 light years.[3]
Naming
- With τ, h, υ, θ, e, and f, it composed the Arabic asterism Sarīr Banāt al-Na'sh, the Throne of the daughters of Na'sh, and al-Haud, the Pond,[4]
- In Chinese, 文昌 (Wén Chāng), meaning Administrative Center, refers to an asterism consisting of φ Ursae Majoris, υ Ursae Majoris, θ Ursae Majoris, 15 Ursae Majoris and 18 Ursae Majoris. Consequently, φ Ursae Majoris itself is known as 文昌三 (Wén Chāng sān, Template:Lang-en.).[5]
References
- ^ Barnaby, David; Spillar, Earl; Christou, Julian.C; Drummond, Jack.D (January 2000), "Measurements of Binary Stars with the Starfire Optical Range Adaptive Optics Systems", The Astronomical Journal, 119 (1): 378–389, Bibcode:2000AJ....119..378B, doi:10.1086/301155
- ^ PHI UMA (Phi Ursae Majoris)
- ^ a b Phi Ursae Majoris (HIP 48402)
- ^ Allen, Richard Hinckley (1899), Star-Names and Their Meanings, New York: G. E. Stechert, p. 442
- ^ Template:Zh icon AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 6 月 16 日
