Zeta Ursae Minoris
 Location of ζ Ursae Minoris. |
|
| Observation data Epoch J2000 Equinox J2000 |
|
|---|---|
| Constellation | Ursa Minor |
| Right ascension | 15h 44m 03.5193s[1] |
| Declination | +77° 47′ 40.175″[1] |
| Apparent magnitude (V) | +4.32[2] |
| Characteristics | |
| Spectral type | A3Vn[3] |
| U−B color index | +0.05[2] |
| B−V color index | +0.04[2] |
| Astrometry | |
| Radial velocity (Rv) | –13.1[4] km/s |
| Proper motion (μ) | RA: 20.07[1] mas/yr Dec.: –2.50[1] mas/yr |
| Parallax (π) | 8.68 ± 0.47[1] mas |
| Distance | 380 ± 20 ly (115 ± 6 pc) |
| Other designations | |
Zeta Ursae Minoris (ζ UMi, ζ Ursae Minoris) is a star in the constellation Ursa Minor. It has the traditional name Akhfa al Farkadain,[6] from the Arabic أخفى الفرقدين aḫfa al-farqadayn "the dimmer of the two calves", as opposed to Anwar al Farkadain (η UMi) "the brighter of the two calves"[citation needed]. These names were originally applied to Pherkad and Kochab, respectively, the other two stars in the rectangle of Ursa Minor.
Zeta Ursae Minoris is a white stellar class A-type main sequence star with an apparent magnitude of +4.28.[7] It is approximately 380 light years from Earth.
Despite its classification as a main sequence dwarf star, Zeta UMi is 3.4 times the mass of the sun and its luminosity is about 200 solar luminosities. At a surface temperature of 8,700 kelvins, this star is actually on the verge of becoming a giant star. Zeta UMi may also be a variable of the Delta Scuti type.[8]
References
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- ↑ 2.0 2.1 2.2 Lua error in package.lua at line 80: module 'strict' not found.
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- ↑ Lua error in package.lua at line 80: module 'strict' not found.
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- ↑ Arabic Star Names
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
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