Iota_Centauri

Iota Centauri

Iota Centauri

Star in the constellation Centaurus

Iota Centauri, Latinized from ι Centauri, is a star in the southern constellation of Centaurus. Based upon parallax measurements, it lies at a distance of approximately 58.6 light-years (18.0 parsecs) from Earth.[1] Iota Centauri has an apparent visual magnitude of +2.73,[2] making it easily visible to the naked eye.

Quick Facts Constellation, Right ascension ...

In Chinese, 柱 (Zhǔ), meaning Pillars, refers to an asterism consisting of ι Centauri, υ2 Centauri, υ1 Centauri, a Centauri, ψ Centauri, 4 Centauri, 3 Centauri and 1 Centauri.[11] Consequently, the Chinese name for ι Centauri itself is 柱十一 (Zhǔ shíyī, English: the Eleventh Star of Pillars.)[12]

The spectrum of ι Centauri matches a stellar classification of A2 V. It is an A-type main sequence star that is generating energy by the nuclear fusion of hydrogen in its core region. This energy is being radiated from the outer envelope of the star at an effective temperature of 8,600 K,[8] giving the star a white hue.[13] It has about 2.5 times the Sun's mass and is roughly 350 million years old.[6] The abundance of elements other than hydrogen and helium, what astronomers term the metallicity, is only 35% of the abundance in the Sun.[8] A weak magnetic field has been tentatively identified with a strength of −77 ± 30 G.[14]

This star has an excess emission of infrared indicating it is surrounded by a circumstellar disk of dust, known as a debris disk. The disk is located within an orbital radius of six Astronomical Units from the star. The dust is unusually luminous for a star this age, suggesting that some process may have recently increased the amount of debris, such as collisions between planetesimals. Alternatively, the planetesimals in this system may have unusual physical properties. As of 2011, a search for planets in this system has thus far been unsuccessful.[6]

Iota Centauri appears to belong to the stellar kinematic group known as IC 2391. This is a group of around 16 co-moving stars that most likely originated in the same molecular cloud at least 45 million years ago.[15]

References

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    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, S2CID 18759600
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    Johnson, H. L.; et al. (1966). "UBVRIJKL photometry of the bright stars". Communications of the Lunar and Planetary Laboratory. 4 (99): 99. Bibcode:1966CoLPL...4...99J.
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    Quanz, Sascha P.; et al. (August 2011), "Searching for Gas Giant Planets on Solar System Scales: VLT NACO/APP Observations of the Debris Disk Host Stars HD172555 and HD115892", The Astrophysical Journal Letters, 736 (2): L32, arXiv:1106.4528, Bibcode:2011ApJ...736L..32Q, doi:10.1088/2041-8205/736/2/L32, S2CID 118506333
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    (in 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.
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    (in Chinese) AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 7 月 25 日
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    "The Colour of Stars", Australia Telescope, Outreach and Education, Commonwealth Scientific and Industrial Research Organisation, December 21, 2004, archived from the original on March 18, 2012, retrieved 2012-01-16
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    Hubrig, S.; et al. (February 2006), "Accurate magnetic field measurements of Vega-like stars and Herbig Ae/Be stars", Astronomy and Astrophysics, 446 (3): 1089–1094, arXiv:astro-ph/0510157, Bibcode:2006A&A...446.1089H, doi:10.1051/0004-6361:20053794, S2CID 14669402
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    Nakajima, Tadashi; Morino, Jun-Ichi; Fukagawa, Misato (September 2010), "Potential Members of Stellar Kinematical Groups within 20 pc of the Sun", The Astronomical Journal, 140 (3): 713–722, Bibcode:2010AJ....140..713N, doi:10.1088/0004-6256/140/3/713
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