Gamma Serpentis
| Observation data Epoch J2000 Equinox J2000 |
|
|---|---|
| Constellation | Serpens |
| Right ascension | 15h 56m 27.18269s[1] |
| Declination | +15° 39′ 41.8206″[1] |
| Apparent magnitude (V) | 3.85[2] |
| Characteristics | |
| Spectral type | F6 V[2] |
| U−B color index | -0.03[3] |
| B−V color index | +0.48[2] |
| Variable type | Suspected[4] |
| Astrometry | |
| Radial velocity (Rv) | 6.78 ± 0.09[5] km/s |
| Proper motion (μ) | RA: 310.93 ± 0.20[1] mas/yr Dec.: -1282.19 ± 0.18[1] mas/yr |
| Parallax (π) | 88.86 ± 0.18[1] mas |
| Distance | 36.70 ± 0.07 ly (11.25 ± 0.02 pc) |
| Details | |
| Mass | 1.30 ± 0.15[6] M☉ |
| Radius | 1.55 ± 0.05[6] R☉ |
| Luminosity | 3.02 ± 0.09[6] L☉ |
| Surface gravity (log g) | 4.23[2] cgs |
| Temperature | 6,350 ± 310[2] K |
| Metallicity [Fe/H] | −0.19[6] dex |
| Rotational velocity (v sin i) | 10.2[6] km/s |
| Age | 3.49[7] Gyr |
| Other designations | |
Gamma Serpentis (γ Serpentis, γ Ser) is a star in the equatorial constellation Serpens, in the part of the constellation that represents the serpent's head (Serpens Caput). It has an apparent visual magnitude +3.85,[2] which means it is visible to the naked eye. Based upon parallax measurements by the Hipparcos spacecraft, this star is approximately 36.7 light years from Earth.[1]
Properties
Gamma Serpentis is an ordinary F-type main sequence star with a stellar classification of F6 V.[2] It is larger and more massive than the Sun, with three times the solar luminosity.[6] Based upon its mass, it may have a convection zone in its core region.[4] The projected rotational velocity along the equator is 10.2[6] km/s. It is younger than the Sun with an estimated age of 3.5 billion years.[7] The effective temperature of the star's outer atmosphere is 6,350 K,[2] giving it the yellow-white-hued glow of an F-type star.[9]
Occasionally Gamma Serpentis is listed as having two 10th magnitude companions, but it appears that these stars are just optical neighbours.
Etymology
It was a member of indigenous Arabic asterism al-Nasaq al-Sha'āmī, "the Northern Line" of al-Nasaqān "the Two Lines",[10] along with β Her (Kornephoros), γ Her (Hejian, Ho Keen) and β Ser (Chow).[11]
According to the catalogue of stars in the Technical Memorandum 33-507 - A Reduced Star Catalog Containing 537 Named Stars, al-Nasaq al-Sha'āmī or Nasak Shamiya were the title for three stars:β Ser as Nasak Shamiya I, γ Ser as Nasak Shamiya II, γ Her as Nasak Shamiya III (exclude β Her).[12] The star was later given the proper name Ainalhai, from the Arabic عين الحية ‘Ayn al-Ḥayyah "the Serpent's Eye".
In Chinese, 天市右垣 (Tiān Shì Yòu Yuán), meaning Right Wall of Heavenly Market Enclosure, refers to an asterism which is represent eleven old states in China which is marking the right borderline of the enclosure, consisting of γ Serpentis, β Herculis, γ Herculis, κ Herculis, β Serpentis, δ Serpentis, α Serpentis, ε Serpentis, δ Ophiuchi, ε Ophiuchi and ζ Ophiuchi.[13] Consequently, γ Serpentis itself is known as 天市右垣四 (Tiān Shì Yòu Yuán sì, English: the Fourth Star of Right Wall of Heavenly Market Enclosure), represent the state Zheng (鄭) (or Ching),[14][15][16] together with 20 Capricorni in Twelve States (asterism).
References
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 Lua error in package.lua at line 80: module 'strict' not found. Vizier catalog entry
- ↑ 2.0 2.1 2.2 2.3 2.4 2.5 2.6 2.7 Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ 4.0 4.1 Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ 6.0 6.1 6.2 6.3 6.4 6.5 6.6 Lua error in package.lua at line 80: module 'strict' not found.
- ↑ 7.0 7.1 Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Jack W. Rhoads - Technical Memorandum 33-507-A Reduced Star Catalog Containing 537 Named Stars, Jet Propulsion Laboratory, California Institute of Technology; November 15, 1971
- ↑ (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.
- ↑ Star Names - R.H.Allen p.376
- ↑ (Chinese) AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 6 月 24 日
- ↑ (Chinese) English-Chinese Glossary of Chinese Star Regions, Asterisms and Star Name, Hong Kong Space Museum. Accessed on line November 23, 2010.
External links
- Gamma Serpentis by Professor Jim Kaler.
