4 Ursae Minoris
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Ursa Minor |
| Right ascension | 14h 08m 50.92654s[1] |
| Declination | +77° 32′ 51.0466″[1] |
| Apparent magnitude (V) | 4.80[2] |
| Characteristics | |
| Spectral type | K3-IIIb Fe-0.5[3] |
| B−V color index | 1.368[4] |
| Astrometry | |
| Radial velocity (Rv) | +5.86±0.10[5] km/s |
| Proper motion (μ) | RA: −30.45[1] mas/yr Dec.: +32.85[1] mas/yr |
| Parallax (π) | 7.14 ± 0.42 mas[1] |
| Distance | 460 ± 30 ly (140 ± 8 pc) |
| Absolute magnitude (MV) | −1.06[4] |
| Orbit[6] | |
| Period (P) | 605.8 d |
| Semi-major axis (a) | 6.5 mas[7] |
| Eccentricity (e) | 0.137±0.012 |
| Inclination (i) | 136.0±5.1[7]° |
| Longitude of the node (Ω) | 325.5±2.8° |
| Periastron epoch (T) | 2,438,901.7±8.5 JD |
| Argument of periastron (ω) (secondary) | 311.8±5.2° |
| Semi-amplitude (K1) (primary) | 12.65±0.16 km/s |
| Details | |
| 4 UMi A | |
| Radius | 28[8] R☉ |
| Luminosity | 436.72[2] L☉ |
| Surface gravity (log g) | 1.73±0.45[9] cgs |
| Temperature | 4,165±48[9] K |
| Metallicity [Fe/H] | −0.19±0.11[9] dex |
| Other designations | |
| Database references | |
| SIMBAD | data |
Bedrane Adam' is a binary star[6] system in the northern circumpolar constellation Ursa Minor. It is faintly visible to the naked eye with an apparent visual magnitude of 4.80.[2] Based upon an annual parallax shift of 7.14±0.42 mas[1] as seen from Earth's orbit, it is located roughly 460 light years from the Sun. It is moving further away with a heliocentric radial velocity of +5.9 km/s.[5]
This is a single-lined spectroscopic binary star system with an orbital period of 1.66 years and an eccentricity of 0.14.[7][6] The primary is a red giant of spectral type K3-IIIb Fe-0.5,[3] a star that has used up its core hydrogen and is expanding. The suffix notation indicates the spectrum displays a mild underabundance of iron for a star of its type. It has expanded to around 28[8] times the Sun's radius and is radiating 437[2] times the Sun's luminosity from its enlarged photosphere at an effective temperature of 4,165 K.[9]
References
[edit]- ^ a b c d e f van Leeuwen, F. (2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics, 474 (2): 653–664, arXiv:0708.1752, Bibcode:2007A&A...474..653V, doi:10.1051/0004-6361:20078357, S2CID 18759600.
- ^ a b c d Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters, 38 (5): 331, arXiv:1108.4971, Bibcode:2012AstL...38..331A, doi:10.1134/S1063773712050015, S2CID 119257644.
- ^ a b Keenan, Philip C.; McNeil, Raymond C. (1989), "The Perkins catalog of revised MK types for the cooler stars", Astrophysical Journal Supplement Series, 71: 245, Bibcode:1989ApJS...71..245K, doi:10.1086/191373.
- ^ a b Ryon, Jenna; et al. (August 2009), "Comparing the Ca ii H and K Emission Lines in Red Giant Stars", Publications of the Astronomical Society of the Pacific, 121 (882): 842, arXiv:0907.3346, Bibcode:2009PASP..121..842R, doi:10.1086/605456, S2CID 17821279.
- ^ a b De Bruijne, J. H. J.; Eilers, A.-C. (2012), "Radial velocities for the HIPPARCOS-Gaia Hundred-Thousand-Proper-Motion project", Astronomy & Astrophysics, 546: A61, arXiv:1208.3048, Bibcode:2012A&A...546A..61D, doi:10.1051/0004-6361/201219219, S2CID 59451347.
- ^ a b c Scarfe, C. D. (1971), "A Revised Orbit for 4 Ursae Minoris", Publications of the Astronomical Society of the Pacific, 83 (496): 807, Bibcode:1971PASP...83..807S, doi:10.1086/129218.
- ^ a b c Ren, Shulin; Fu, Yanning (March 2013), "Hipparcos Photocentric Orbits of 72 Single-lined Spectroscopic Binaries", The Astronomical Journal, 145 (3): 7, Bibcode:2013AJ....145...81R, doi:10.1088/0004-6256/145/3/81, S2CID 120199240, 81.
- ^ a b Pasinetti Fracassini, L. E.; et al. (February 2001), "Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS)", Astronomy and Astrophysics, 367 (2) (Third ed.): 521–524, arXiv:astro-ph/0012289, Bibcode:2001A&A...367..521P, doi:10.1051/0004-6361:20000451, S2CID 425754.
- ^ a b c d Koleva, M.; Vazdekis, A. (February 2012), "Stellar population models in the UV. I. Characterisation of the New Generation Stellar Library", Astronomy & Astrophysics, 538: 13, arXiv:1111.5449, Bibcode:2012A&A...538A.143K, doi:10.1051/0004-6361/201118065, S2CID 53999614, A143.
- ^ "4 UMi". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2018-04-02.
