Xi Draconis
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Draco |
| Right ascension | 17h 53m 31.72962s[1] |
| Declination | +56° 52′ 21.5143″[1] |
| Apparent magnitude (V) | 3.75[2] |
| Characteristics | |
| Spectral type | K2 III[3] |
| U−B color index | +1.21[2] |
| B−V color index | +1.18[2] |
| Astrometry | |
| Radial velocity (Rv) | -26.38 ± 0.20[4] km/s |
| Proper motion (μ) | RA: 93.82 ± 0.14[1] mas/yr Dec.: 78.50 ± 0.12[1] mas/yr |
| Parallax (π) | 28.98 ± 0.12[1] mas |
| Distance | 112.5 ± 0.5 ly (34.5 ± 0.1 pc) |
| Details | |
| Mass | 1.45 ± 0.17[5] M☉ |
| Radius | 12[6] R☉ |
| Luminosity | 49 ± 4[5] L☉ |
| Surface gravity (log g) | 2.3[6] cgs |
| Temperature | 4,445[5] K |
| Metallicity [Fe/H] | –0.09[6] dex |
| Rotational velocity (v sin i) | 2.3[6] km/s |
| Other designations | |
Xi Draconis (ξ Dra, ξ Draconis) is the Bayer designation for a star in the northern circumpolar constellation of Draco. It has the traditional name Grumium or Genam. This star, along with β Dra (Rastaban), γ Dra (Eltanin), μ Dra (Erakis) and ν Dra (Kuma) were Al ʽAwāïd, "the Mother Camels", which was later known as the Quinque Dromedarii.[7] This star has an apparent visual magnitude of 3.75.[2] Based upon parallax measurements, it is located at a distance of 112.5 light-years (34.5 parsecs) from Earth.[1] At this distance, the apparent magnitude is diminished by 0.03 from extinction caused by intervening gas and dust.[4]
In Chinese, 天棓 (Tiān Bàng), meaning Celestial Flail, refers to an asterism consisting of ξ Draconis, ν Draconis, β Draconis, γ Draconis and ι Herculis.[8] Consequently, δ Draconis itself is known as 天棓一 (Tiān Bàng yī, English: the First Star of Celestial Flail.)[9]
Structure
Xi Draconis is of spectral class K2-III.
Namesakes
USS Grumium (AK-112) was a United States Navy Crater class cargo ship named after the star.
References
- 1 2 3 4 5 6 van Leeuwen, F. (November 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.
- 1 2 3 4 Jennens, P. A.; Helfer, H. L. (September 1975), "A new photometric metal abundance and luminosity calibration for field G and K giants.", Monthly Notices of the Royal Astronomical Society 172: 667–679, Bibcode:1975MNRAS.172..667J, doi:10.1093/mnras/172.3.667.
- ↑ Morgan, W. W.; Keenan, P. C. (1973), "Spectral Classification", Annual Review of Astronomy and Astrophysics 11: 29–50, Bibcode:1973ARA&A..11...29M, doi:10.1146/annurev.aa.11.090173.000333.
- 1 2 Famaey, B.; et al. (January 2005), "Local kinematics of K and M giants from CORAVEL/Hipparcos/Tycho-2 data. Revisiting the concept of superclusters", Astronomy and Astrophysics 430 (1): 165–186, arXiv:astro-ph/0409579, Bibcode:2005A&A...430..165F, doi:10.1051/0004-6361:20041272.
- 1 2 3 Stello, D.; et al. (2008), "Oscillating K Giants with the WIRE Satellite: Determination of Their Asteroseismic Masses", The Astrophysical Journal Letters 674 (1): L53–L56, arXiv:0801.2155, Bibcode:2008ApJ...674L..53S, doi:10.1086/528936.
- 1 2 3 4 Massarotti, Alessandro; et al. (January 2008), "Rotational and Radial Velocities for a Sample of 761 HIPPARCOS Giants and the Role of Binarity", The Astronomical Journal 135 (1): 209–231, Bibcode:2008AJ....135..209M, doi:10.1088/0004-6256/135/1/209.
- ↑ Allen, R. H. (1963), Star Names: Their Lore and Meaning (Reprint ed.), New York, NY: Dover Publications Inc., p. 207, ISBN 0-486-21079-0, retrieved 2010-12-12.
- ↑ (Chinese) 中國星座神話, written by 陳久金. Published by 台灣書房出版有限公司, 2005, ISBN 978-986-7332-25-7.
- ↑ (Chinese) 香港太空館 - 研究資源 - 亮星中英對照表, Hong Kong Space Museum. Accessed on line November 23, 2010.
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