14h50m20s, +82° 30′43″| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Ursa Minor |
| Right ascension | 14h50m 20.421s[1] |
| Declination | +82° 30′ 42.99″[1] |
| Apparent magnitude (V) | 5.63[2] |
| Characteristics | |
| Spectral type | G2V[3] |
| U−B color index | +0.17[4] |
| B−V color index | +0.671±0.004[2] |
| Astrometry | |
| Radial velocity (Rv) | −44.38[5] km/s |
| Proper motion (μ) | RA: +177.593 mas/yr[1] Dec.: −224.260 mas/yr[1] |
| Parallax (π) | 22.9030 ± 0.0496 mas[1] |
| Distance | 142.4 ± 0.3 ly (43.66 ± 0.09 pc) |
| Absolute magnitude (MV) | 2.448[5] |
| Details | |
| HD 133002 A | |
| Mass | 1.51[6] M☉ |
| Radius | 3.4[1] R☉ |
| Luminosity | 9.54±0.04[1] L☉ |
| Surface gravity (log g) | 3.86[7] cgs |
| Temperature | 5,515±1[1] K |
| Metallicity [Fe/H] | −0.41[8] dex |
| Rotational velocity (v sin i) | 5.2[7] km/s |
| Age | 2.80[6] Gyr |
| HD 133002 B | |
| Mass | 0.15±0.01[9] M☉ |
| Other designations | |
BD+83°431, FK5 1644, GJ 3876, HD 133002, HIP 72573, HR 5596, SAO 2459[10] | |
| Database references | |
| SIMBAD | data |
| ARICNS | data |
HD 133002 (HR 5596) is a possible binary[9] star in the northern constellationofUrsa Minor. With an apparent visual magnitude of 5.65,[4] it is faintly visible to the naked eye. (According to the Bortle scale, it can be viewed from dark rural skies.) The high declination of +82.5°[1] means it is hidden from view from most of the southern hemisphere. Parallax measurements yield an estimated distance of around 142 light years from the Sun.[1] If it was instead positioned at a distance of 33 ly (10 pc), this would be a second magnitude star.[5] The system is drifting closer with a heliocentric radial velocity of −44 km/s.[5]
This is a G-type main sequence star with a stellar classification of G2V,[3] although it has also been classified as F9V or G0V.[11] With spectral absorption lines of metals and absorption bands of some molecules weaker than expected based on its hydrogen lines, it is defined as a weak line star. Based on its G-band strengths, it would we given a class of G0, and based on its metal lines a class of G1.[3]
It is estimated to have 51% greater mass than the Sun, and is younger with an age of around 2.8 billion years.[6] The projected rotational velocity along the star's equator is a relatively leisurely 5.2 km/s.[7] The star is considered a photometric solar analog, although it is deficient in elements more massive than helium when compared to the Sun.[12] The chemical composition and relatively low surface gravity for a star of its classification suggest that this may instead be a subgiant star that is in the process of evolving away from the main sequence.[13] The effective temperature of the star's photosphereis5,515 K,[1] giving it the yellow-white hue of a G-type star.[14]
This star has been examined for evidence of an infrared excess, but none was detected.[15] During a 2006−2007 survey of nearby stars, it was discovered that HD 133002 has a low-mass common proper motion stellar companion. This object has an estimated 15% of the Sun's mass. It has a projected separation of around 80 AU from the primary, which suggests an orbital period of roughly 700 years. At present, there is insufficient observational data available to determine orbital elements.[9]
{{cite web}}: CS1 maint: postscript (link)
