GJ 440
观测资料 历元 J2000.0 (ICRS) | |
---|---|
星座 | 苍蝇座[1] |
星官 | |
赤经 | 11h 45m 42.9205s[2] |
赤纬 | −64° 50′ 29.459″[2] |
视星等(V) | 11.50[2] |
特性 | |
光谱分类 | DQ6[3] |
U−B 色指数 | -0.59[2] |
B−V 色指数 | +0.19[2] |
天体测定 | |
自行 (μ) | 赤经:2665.25[2] mas/yr 赤纬:-346.19[2] mas/yr |
视差 (π) | 215.6753 ± 0.0181[4] mas |
距离 | 15.123 ± 0.001 ly (4.6366 ± 0.0004 pc) |
详细资料 | |
质量 | 0.56 ± 0.08[5] M☉ |
半径 | 0.01 R☉ |
表面重力 (log g) | 8.27 ± 0.05[6] |
亮度 | 0.0005[6] L☉ |
温度 | 8,500 ± 300[6] K |
年龄 | (白矮星年龄)[6] 1.44 Gyr |
其他命名 | |
参考数据库 | |
SIMBAD | 资料 |
GJ 440在苍蝇座的位置 |
LP 145-141 (亦可称为GJ 440、LAWD 37[15])是一颗位于苍蝇座的白矮星,距离太阳系15光年。[16] 根据 2009 年的一篇论文,它是已知白矮星之中距离太阳第四近的 (由近至远依次为天狼星B,南河三B和范马南星。)[17]
空间运动
GJ 440可能是Wolf219移动星群的成员,该群有七个可能的成员。这些恒星在太空中有相似的运动,这可能表明它们有共同的起源。[18] 这些恒星的估计空间速度为160公里/秒,并且沿着一条高度偏心的轨道穿过银河系。[19]
特性
白矮星不再通过核聚变在其核心产生能量,而是稳定地散发掉它们剩余的热量。GJ 440有一个 DQ光谱分类,表明它是一种罕见的白矮星,在其光谱中显示出原子或分子碳的证据。[20]
2019 年,观察到GJ 440从一颗更远的恒星前经过。哈勃太空望远镜观测到的GJ 440的引力场使星光发生弯曲,从而可以直接测量其质量。GJ 440的估计质量为 0.56±0.08M☉,符合具有碳氧核心的白矮星的预期范围。这一测量标志着首次直接测定单个白矮星的引力质量。[5]
它是一颗估计有 4.4 个太阳质量的大质量主序星的恒星残骸。[21] 虽然它在主序带上,但它可能是一颗光谱B 级恒星(在 B4-B9 范围内)。[22] 恒星的大部分原始质量在进入渐近巨星分支阶段后,就在成为白矮星之前脱落。
伴星搜索
哈勃太空望远镜的一项调查显示,在探测范围内没有可见的轨道伴星。[23][3]
它的距离、质量和温度使它被认为是寻找类木行星的一个很好的候选者。它相对较大的质量和较高的温度意味着该系统的寿命相对较短,因此起源较晚。[24]
参见
参考资料
- ^ Constellation boundaries. Centre de Données astronomiques de Strasbourg. [2007-07-16]. (原始内容存档于2019-07-17).
- ^ 2.0 2.1 2.2 2.3 2.4 2.5 2.6 LAWD 37. SIMBAD. 斯特拉斯堡天文资料中心. [2007-07-16].
- ^ 3.0 3.1 Daniel J. Schroeder; et al. A Search for Faint Companions to Nearby Stars Using the Wide Field Planetary Camera 2. The Astronomical Journal. February 2000, 119 (2): 906–922. Bibcode:2000AJ....119..906S. doi:10.1086/301227 .
- ^ Brown, A. G. A.; et al. Gaia Early Data Release 3: Summary of the contents and survey properties. Astronomy & Astrophysics. 2021, 649: A1. Bibcode:2021A&A...649A...1G. S2CID 227254300. arXiv:2012.01533 . doi:10.1051/0004-6361/202039657 . 已忽略未知参数
|collaboration=
(帮助) (勘误: doi:10.1051/0004-6361/202039657e). Gaia EDR3 record for this source at VizieR. - ^ 5.0 5.1 McGill, P.; Anderson, J.; Casertano, S.; Sahu, K.C., First semi-empirical test of the white dwarf mass-radius relationship using a single white dwarf via astrometric microlensing, Monthly Notices of the Royal Astronomical Society, March 2023, 520 (1): 259–280 [2023-02-08], doi:10.1093/mnras/stac3532
- ^ 6.0 6.1 6.2 6.3 Table 2, P. Bergeron; S. K. Leggett; María Teresa Ruiz. Photometric and Spectroscopic Analysis of Cool White Dwarfs with Trigonometric Parallax Measurements. Astrophysical Journal Supplement Series. April 2001, 133 (2): 413–449. Bibcode:2001ApJS..133..413B. S2CID 15511301. arXiv:astro-ph/0011286 . doi:10.1086/320356.
- ^ Gliese, W.; Jahreiß, H. Gl 440. Preliminary Version of the Third Catalogue of Nearby Stars. 1991 [2023-03-20]. (原始内容存档于2016-03-04).
- ^ Perryman; et al. HIP 57367. The Hipparcos and Tycho Catalogues. 1997 [2023-03-20]. (原始内容存档于2016-03-04).
- ^ Porter, J. G.; Yowell, E. J.; Smith, E. S. A catalogue of 1474 stars with proper motion exceeding four-tenths year.. Publications of the Cincinnati Observatory. 1930, 20: 1–32. Bibcode:1930PCinO..20....1P. Page 16 (Ci 20 658). (页面存档备份,存于互联网档案馆)
- ^ Luyten, Willem Jacob. LHS 30. LHS Catalogue, 2nd Edition. 1979 [2023-03-20]. (原始内容存档于2016-03-04).
- ^ Luyten, Willem Jacob. NLTT 28447. NLTT Catalogue. 1979 [2023-03-20]. (原始内容存档于2016-03-04).
- ^ Van Altena W. F.; Lee J. T.; Hoffleit E. D. GCTP 2716. The General Catalogue of Trigonometric Stellar Parallaxes Fourth. 1995 [2023-03-20]. (原始内容存档于2016-03-04).
- ^ Perryman; et al. HIP 57367. The Hipparcos and Tycho Catalogues. 1997 [2023-03-20]. (原始内容存档于2016-03-04).
- ^ Hog; et al. TYC 8981-4417-1. The Tycho-2 Catalogue. 2000 [2023-03-20]. (原始内容存档于2016-03-04).
- ^ Lawd 37. [2023-03-20]. (原始内容存档于2023-03-21).
- ^ Henry, Todd J.; Walkowicz, Lucianne M.; Barto, Todd C.; Golimowski, David A. The Solar Neighborhood. VI. New Southern Nearby Stars Identified by Optical Spectroscopy. The Astronomical Journal. April 2002, 123 (4): 2002–2009. Bibcode:2002AJ....123.2002H. S2CID 17735847. arXiv:astro-ph/0112496 . doi:10.1086/339315.
- ^ Table 1, Sion Edward M. The white dwarfs within 20 parsecs of the sun: kinematics and statistics. The Astronomical Journal. 2009, 138 (6): 1681–1689. Bibcode:2009AJ....138.1681S. S2CID 119284418. arXiv:0910.1288 . doi:10.1088/0004-6256/138/6/1681.
- ^ Eggen, O. J.; Greenstein, J. L. Spectra, colors, luminosities, and motions of the white dwarfs. Astrophysical Journal. 1965, 141: 83–108. Bibcode:1965ApJ...141...83E. doi:10.1086/148091. — see table 5.
- ^ Bell, R. A. Observations of some southern white dwarfs. The Observatory. 1962, 82: 68–71. Bibcode:1962Obs....82...68B.
- ^ Kawaler, S.; Dahlstrom, M. White Dwarf Stars. American Scientist. 2000, 88 (6): 498 [2007-07-19]. Bibcode:2000AmSci..88..498K. S2CID 227226657. doi:10.1511/2000.6.498. (原始内容存档于April 18, 2005).
- ^ Burleigh, M. R.; Clarke, F. J.; Hodgkin, S. T. Imaging planets around nearby white dwarfs. Monthly Notices of the Royal Astronomical Society. April 2002, 331 (4): L41–L45. Bibcode:2002MNRAS.331L..41B. S2CID 18383063. arXiv:astro-ph/0202194 . doi:10.1046/j.1365-8711.2002.05417.x.
- ^ Siess, Lionel. Computation of Isochrones. Institut d'Astronomie et d'Astrophysique, Université libre de Bruxelles. 2000 [2007-03-24]. (原始内容存档于2011-05-05).
- ^ Jao, Wei-Chun; Henry, Todd J.; Subasavage, John P.; Brown, Misty A.; Ianna, Philip A.; Bartlett, Jennifer L.; Costa, Edgardo; Méndez, René A. The Solar Neighborhood. XIII. Parallax Results from the CTIOPI 0.9 Meter Program: Stars with mu >= 1.0" yr-1 (MOTION Sample). The Astronomical Journal. 2005, 129 (4): 1954–1967. Bibcode:2005AJ....129.1954J. S2CID 16164903. arXiv:astro-ph/0502167 . doi:10.1086/428489.
- ^ Burleigh, Matthew R.; Clarke, F.J.; Hodgkin, S.T. Imaging Planets around Nearby White Dwarfs. Monthly Notices of the Royal Astronomical Society. 2002, 331 (4): L41–L45. Bibcode:2002MNRAS.331L..41B. S2CID 18383063. arXiv:astro-ph/0202194 . doi:10.1046/j.1365-8711.2002.05417.x.