zh %E6%A0%BC%E5%88%A9%E6%B3%BD229

**格利澤229**
	; 格利澤229 A和B。
觀測資料; 曆元 J2000
星座	天兔座
星官
赤經	06h 10m 34.6154s
赤緯	−21° 51′ 52.715″
視星等（V）	8.14
特性
光谱分类	M1Ve
U−B 色指数	+1.222
B−V 色指数	+1.478
变星类型	焰星
天体测定
徑向速度 (Rv)	+3.9 km/s
自行 (μ)	赤经：–137.01 mas/yr ; 赤纬：–714.05 mas/yr
视差 (π)	173.19 ± 1.12 mas
距离	18.8 ± 0.1 ly ; (5.77 ± 0.04 pc)
绝对星等 (MV)	9.33
	軌道
伴星	Gliese 229 B
繞行週期 (P)	216.925+10.604; −10.352 yr
半長軸 (a)	28.933+1.008; −1.000 AU
偏心率 (e)	0.853±0.002
倾斜角 (i)	5.497+0.153; −0.162°
升交点黃經 (Ω)	145.946+0.306; −0.294°
近心点曆元 (T)	2466912+97; −63
近心點幅角 (ω); (secondary)	358.285+0.836; −0.846°
半振幅 (K1); (primary)	0.081674+0.001688; −0.001680 km/s
詳細資料
質量	0.58 M☉
半徑	0.69 R☉
溫度	3,700 K
自轉速度 (v sin i)	1 km/s
其他命名
	BD-21°1377, HD 42581, HIP 29295, LHS 1827, NSV 2863, SAO 171334, TYC 5945- 765-1

格利澤229 (也可以寫成Gl 229或GJ 229) 是在天兔座內距離地球大約19光年的一顆紅矮星。它的質量是58%太陽質量^[6]，半徑是 69%太陽半徑^[7]，和在赤道只有1公里/秒，非常低的投影轉速^[9]。

已知這顆恆星是低活動的焰星，這意味著它曾經是一顆表面亮度會因為磁場活動而隨意變化的恆星。頻譜中顯示出鈣的H和K發射譜線，在冕部的光譜中也曾經檢測出X射線^[10]，這可能是磁場迴圈與恆星外圍的大氣層交互作用引起的，但沒有檢測到大規模的黑子活動^[2]。

在1994年拍到次恆星伴星格利澤229B的影像，並在1995年獲得證實。它是一顆棕矮星。雖然是一顆質量太小，無法維持氫的核融合的恆星，它的質量大約是木星的20至50倍，對行星而言是太重了 2024年被發現木星質量的38倍和34倍，12天旋轉一次是一對緻密棕矮星。格利澤229B是第一顆被確認的次恆星質量的天體，表面溫度大約是950K^[11]。

這顆恆星的空間速度分量是U = +12，V = –11，和W = –12 公里/秒^[12]。這顆恆星以0.07的離心率和0.005的軌道傾角在銀河系中穿越著^[2]。

參考資料

^ ^1.0 ^1.1 ^1.2 ^1.3 ^1.4 Perryman, M. A. C.; et al. 依巴谷星表. Astronomy and Astrophysics. 1997, 323: L49–L52. Bibcode:1997A&A...323L..49P.
^ ^2.0 ^2.1 ^2.2 ^2.3 ^2.4 Byrne, P. B.; Doyle, J. G.; Menzies, J. W. Optical photometry and spectroscopy of the flare star Gliese 229 (=HD42581). Monthly Notices of the Royal Astronomical Society. May 1, 1985, 214: 119–130 [2009-10-19]. Bibcode:1985MNRAS.214..119B.
^ Evans, D. S. The Revision of the General Catalogue of Radial Velocities. Batten, Alan Henry; Heard, John Frederick (编). Determination of Radial Velocities and their Applications, Proceedings from IAU Symposium no. 30. University of Toronto: International Astronomical Union. June 20–24, 1966 [2009-10-19]. （原始内容存档于2019-06-26）.
^ 引用错误：没有为名为Brandt2021的参考文献提供内容
^ 引用错误：没有为名为Feng2022的参考文献提供内容
^ ^6.0 ^6.1 Zechmeister, M.; Kürster, M.; Endl, M. The M dwarf planet search programme at the ESO VLT + UVES. A search for terrestrial planets in the habitable zone of M dwarfs. Astronomy and Astrophysics. October 2009, 505 (2): 859–871. doi:10.1051/0004-6361/200912479.
^ ^7.0 ^7.1 White, Stephen M.; Jackson, Peter D.; Kundu, Mukul R. A VLA survey of nearby flare stars. Astrophysical Journal Supplement Series. December 1989, 71: 895–904. doi:10.1086/191401.
^ Morales, J. C.; Ribas, I.; Jordi, C. The effect of activity on stellar temperatures and radii. Astronomy and Astrophysics. February 2008, 478 (2): 507–512. doi:10.1051/0004-6361:20078324. Data from CDS table J/A+A/478/507.
^ ^9.0 ^9.1 Reiners, A. The narrowest M-dwarf line profiles and the rotation-activity connection at very slow rotation. Astronomy and Astrophysics. May 2007, 467 (1): 259–268. doi:10.1051/0004-6361:20066991.
^ Schmitt JHMM, Fleming TA, Giampapa MS. The X-Ray View of the Low-Mass Stars in the Solar Neighborhood. Ap J. September 1995, 450 (9): 392–400. Bibcode:1995ApJ...450..392S. doi:10.1086/176149.
^ Geißler, K.; Chauvin, G.; Sterzik, M. F. Mid-infrared imaging of brown dwarfs in binary systems. Astronomy and Astrophysics. March 2008, 480 (1): 193–198. doi:10.1051/0004-6361:20078229.
^ Gliese, W. Catalogue of Nearby Stars. Veröffentlichungen des Astronomischen Rechen-Instituts Heidelberg. 1969. Bibcode:1969VeARI..22....1G.

外部連結

Astronomers Announce First Clear Evidence of a Brown Dwarf （页面存档备份，存于互联网档案馆） – STScI news release STScI-1995-48 (November 29, 1995)
Brown dwarfs (NASA)
Extrasolar Visions – Gliese 229
Extrasolar Visions – Gliese 229 b （页面存档备份，存于互联网档案馆）

[aaa323-1] 1.0 ^1.1 ^1.2 ^1.3 ^1.4 Perryman, M. A. C.; et al. 依巴谷星表. Astronomy and Astrophysics. 1997, 323: L49–L52. Bibcode:1997A&A...323L..49P.

[mnras214-2] 2.0 ^2.1 ^2.2 ^2.3 ^2.4 Byrne, P. B.; Doyle, J. G.; Menzies, J. W. Optical photometry and spectroscopy of the flare star Gliese 229 (=HD42581). Monthly Notices of the Royal Astronomical Society. May 1, 1985, 214: 119–130 [2009-10-19]. Bibcode:1985MNRAS.214..119B.

[3] Evans, D. S. The Revision of the General Catalogue of Radial Velocities. Batten, Alan Henry; Heard, John Frederick (编). Determination of Radial Velocities and their Applications, Proceedings from IAU Symposium no. 30. University of Toronto: International Astronomical Union. June 20–24, 1966 [2009-10-19]. （原始内容存档于2019-06-26）.

[Brandt2021-4] 引用错误：没有为名为Brandt2021的参考文献提供内容

[Feng2022-5] 引用错误：没有为名为Feng2022的参考文献提供内容

[aaa505-6] 6.0 ^6.1 Zechmeister, M.; Kürster, M.; Endl, M. The M dwarf planet search programme at the ESO VLT + UVES. A search for terrestrial planets in the habitable zone of M dwarfs. Astronomy and Astrophysics. October 2009, 505 (2): 859–871. doi:10.1051/0004-6361/200912479.

[apjss71-7] 7.0 ^7.1 White, Stephen M.; Jackson, Peter D.; Kundu, Mukul R. A VLA survey of nearby flare stars. Astrophysical Journal Supplement Series. December 1989, 71: 895–904. doi:10.1086/191401.

[8] Morales, J. C.; Ribas, I.; Jordi, C. The effect of activity on stellar temperatures and radii. Astronomy and Astrophysics. February 2008, 478 (2): 507–512. doi:10.1051/0004-6361:20078324. Data from CDS table J/A+A/478/507.

[aaa467-9] 9.0 ^9.1 Reiners, A. The narrowest M-dwarf line profiles and the rotation-activity connection at very slow rotation. Astronomy and Astrophysics. May 2007, 467 (1): 259–268. doi:10.1051/0004-6361:20066991.

[Schmitt-10] Schmitt JHMM, Fleming TA, Giampapa MS. The X-Ray View of the Low-Mass Stars in the Solar Neighborhood. Ap J. September 1995, 450 (9): 392–400. Bibcode:1995ApJ...450..392S. doi:10.1086/176149.

[11] Geißler, K.; Chauvin, G.; Sterzik, M. F. Mid-infrared imaging of brown dwarfs in binary systems. Astronomy and Astrophysics. March 2008, 480 (1): 193–198. doi:10.1051/0004-6361:20078229.

[12] Gliese, W. Catalogue of Nearby Stars. Veröffentlichungen des Astronomischen Rechen-Instituts Heidelberg. 1969. Bibcode:1969VeARI..22....1G.

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格利泽229

參考資料

外部連結

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