2MASS J18082002−5104378

2MASS J18082002−5104378（縮寫為J1808−5104）是一個超貧金屬（UMP）聯星系統，位於天壇座，距離地球大約1,950 ly（600 pc），並且是單線光譜聯星（SB1）。它是已知最古老的恆星之一，約有135.3億年的歷史，可能是最早的恆星之一。這顆恆星幾乎完全由宇宙大爆炸釋放的物質組成。一個看不見的微小伴星，一顆低質量的UMP恆星，特別不尋常。 J1808−5104是一顆超貧金屬（UMP）星，其對數金屬豐度[Fe/H]小於2999600000000000000♠−4，或太陽1/   10,000  的級別。它是一個單線光譜聯星，其光譜吸收線的徑向速度變化被解釋為可見恆星的軌道運動。這顆伴星是看不見的，而僅是從軌道上推斷出來的。 J1808−5104是已知最亮的聯星系統超貧金屬星，是太陽所在星系，銀河系「薄盤」的一部分，但對於這樣一顆缺乏金屬的古老恆星來說是不尋常的。在7017426974328000000♠13.53 Gyr，這顆恆星是已知最古老的薄盤恆星，比大多數對銀河系薄盤年齡的估計要早幾十億年 聯星系統的主要組成部分，2MASS J18082002−5104378 A，是一顆比太陽冷，但更大、更亮的次巨星。 看不見的伴星，2MASS J18082002−5104378 B，被認為是一顆紅矮星 ，軌道週期 P = 7001347570000000000♠34.757+0.010 −0.010日和質量為0.14 M☉。它是第一顆被發現的低質量超貧金屬星，也是宇宙中最古老的恆星之一，約有135.3億年的歷史。它可能是最早的恆星之一，一顆幾乎完全由大爆炸釋放的物質形成的恆星。 Schlaufman, Kevin C.; Thompson, Ian B.; Casey, Andrew R. An ultra metal-poor star near the hydrogen-burning limit. The Astrophysical Journal. 5 November 2018, 867 (2): 98. Bibcode:2018ApJ...867...98S. S2CID 54511945. arXiv:1811.00549 . doi:10.3847/1538-4357/aadd97 .  Finding the constellation which contains given sky coordinates. DJM.cc. 2018 [5 November 2018]. （原始内容存档于2019-08-15）.  Meléndez, Jorge; Placco, Vinicius M.; Tucci-Maia, Marcelo; Ramírez, Iván; Li, Ting S.; Perez, Gabriel. 2MASS J18082002-5104378: The brightest (V = 11.9) ultra metal-poor star. Astronomy and Astrophysics. 2016, 585: L5. Bibcode:2016A&A...585L...5M. S2CID 119240055. arXiv:1601.03462 . doi:10.1051/0004-6361/201527456.  Brown, A. G. A.; Vallenari, A.; Prusti, T.; de Bruijne, J. H. J.; et al. Gaia Data Release 2. Summary of the contents and survey properties. Astronomy & Astrophysics. 2018. Bibcode:2018A&A...616A...1G. arXiv:1804.09365 . doi:10.1051/0004-6361/201833051.  VizieR中此天体在盖亚望远镜第二批数据发布的记录 One of Milky Way's oldest stars discovered. SciNews.com. 6 November 2018 [6 November 2018]. （原始内容存档于2018-11-06）.  Crockett, Christopher. Puny star might be [a] specimen from [the] early universe. Sky & Telescope. 12 November 2018 [14 November 2018]. （原始内容存档于2018-11-12）.  Williams, Matt. Ancient star found that's only slightly younger than the universe itself. Universe Today. 9 November 2018 [14 November 2018]. （原始内容存档于2024-01-26）.  Ezzeddine, Rana; Frevbel, Anna. Revisiting the iron abundance in the hyper iron-poor star HE 1327−2326 with UV COS/HST data. The Astrophysical Journal. 27 September 2018, 863 (2): 168. Bibcode:2018ApJ...863..168E. S2CID 118918067. arXiv:1807.06153 . doi:10.3847/1538-4357/aad3cb .  Rosen, Jill. Johns Hopkins scientist finds elusive star with origins close to Big Bang (新闻稿). Johns Hopkins University. 5 November 2018 [5 November 2018]. （原始内容存档于2018-11-06）. The newly discovered star's composition indicates that, in a cosmic family tree, it could be as little as one generation removed from the Big Bang.  Wehner, Mike. Astronomers spot one of the oldest stars ever. BGR. 5 November 2018 [5 November 2018]. （原始内容存档于2018-11-06）.  A tiny old star has a huge impact. SpaceRef.com (新闻稿). Gemini Observatory. 5 November 2018 [6 November 2018]. [永久失效連結] Johns Hopkins scientist finds elusive star with origins close to Big Bang (新闻稿). Johns Hopkins University. 5 November 2018 [5 November 2018]. （原始内容存档于2018-11-06） –通过EurekAlert!.  Starr, Michelle. Astronomers have detected one of the oldest stars in the entire universe. ScienceAlert.com. 5 November 2018 [5 November 2018]. （原始内容存档于2018-11-05）.  Irving, Michael. 13.5 billion year old star was born just after the Big Bang - and it's in our neighborhood. NewAtlas.com. 5 November 2018 [5 November 2018]. （原始内容存档于2018-11-05）.  Malewar, Amit. Johns Hopkins scientists may have found one of the universe's oldest stars - One of the universe's oldest stars. TechExplorist.com. 5 November 2018 [5 November 2018]. （原始内容存档于2018-11-05）.  2MASS J18082002−5104378. SIMBAD. 斯特拉斯堡天文資料中心.  2MASS J18082002−5104378 B. SIMBAD. 斯特拉斯堡天文資料中心.  YouTube上的Video (00:30) – Orbit of newly found 13.5 billion-year-old star (5 November 2018; Johns Hopkins University) 天文學主題 太空主題