Not to be confused with List of most massive stars known.
Below is a list of the largest known stars by radius. The unit of measurement used is the radius of the Sun (approximately 695,500 kilometers, or 432,450 miles).
The exact order of this list is not complete, nor is it perfectly defined:
- There are sometimes high uncertainties in derived values and sizes;
- The distances to most of these stars are uncertain to differing degrees and this uncertainty affects the size measurements;
- All the stars in this list have extended atmospheres, many are embedded in mostly opaque dust shells or disks, and most pulsate, such that their radii are not well defined;
- There are theoretical reasons for expecting that no stars in the Milky Way are larger than approximately 1,500 times the Sun, based on evolutionary models and the Hayashi instability zone. The exact limit depends on the metallicity of the star, so for example supergiants in the Magellanic Clouds have slightly different limiting temperature and luminosity. Stars exceeding the limit have been seen to undergo large eruptions and to change their spectral type over just a few months;
- A survey of the Magellanic Clouds has catalogued most of the red supergiants and 44 of them are larger than the 700 solar radii cutoff point of this table, with the largest at 1,200–1,300.[1]
Contents
List
Star | Solar radii (Sun = 1) |
Notes | Ref. |
---|---|---|---|
UY Scuti | 1,708 | Margin of error in size determination: ± 192 solar radii. At its smallest, its size would be similar to that of VX Sagittarii (see below). | [2] |
NML Cygni | 1,642–2,775 | NML Cyg is a semiregular variable star surrounded by a circumstellar nebula and is heavily obscured by dust extinction. | [3] |
RW Cephei | 1,636 | RW Cep is variable both in brightness (by at least a factor of 3) and spectral type (observed from G8 to M), thus probably also in diameter. Because the spectral type and temperature at maximum luminosity are not known, the quoted size is just an estimate. | [4][5] |
WOH G64 | 1,540–1,730 | This would be the largest star in the LMC, but is unusual in position and motion and might still be a foreground halo giant. | [6][7] |
Westerlund 1-26 | 1,530 | Very uncertain parameters for an unusual star with strong radio emission. The spectrum is variable but apparently the luminosity is not. | [8] |
VX Sagittarii | 1,520 | VX Sgr is a pulsating variable with a large visual range and varies significantly in size. | [9] |
VV Cephei A | 1,050–1,900 | VV Cep A is a highly distorted star in a binary system, losing mass to its B-type companion VV Cephei B for at least part of its orbit. | |
VY Canis Majoris | 1,420 | Previously thought to be a star so large that it contradicted stellar evolutionary theory, a newly improved measurement has brought it down to size. Margin of possible error: ± 120 solar radii. | [10][11] |
KY Cygni | 1,420 | KY Cygni is located in a region with heavy dust extinction, thus making it hard to determine its size. The quoted size is the value consistent with stellar evolutionary models, the true range may be larger. | [12] |
AH Scorpii | 1,287–1,535 | AH Sco is variable by nearly 3 magnitudes in the visual range, and an estimated 20% in total luminosity. The variation in diameter is not clear because the temperature also varies. | [2] |
HR 5171 A | 1,316 | HR 5171 A is a highly distorted star in a close binary system, losing mass to the secondary. | [13] |
PZ Cassiopeiae | 1,260–1,340 | [14] | |
KW Sagittarii | 1,235 | [2][12] | |
IRC-10414 | 1,200 | [15] | |
BC Cygni | 1,140 | [12] | |
V354 Cephei | 1,104.5 | [9][12] | |
RT Carinae | 1,090 | [12] | |
BI Cygni | 1,078 | [9][12] | |
Betelgeuse (Alpha Orionis) | 950-1,200 | Ninth brightest star in the night sky. | [16] |
V396 Centauri | 1,070 | [12] | |
CK Carinae | 1,060 | [12] | |
Mu Cephei (Herschel's "Garnet Star") | 1,035 | [12][17] | |
S Persei | 1,005 | In the Perseus Double Cluster. | [12] |
RS Persei | 1,000 | In the Perseus Double Cluster. | [12] |
NR Vulpeculae | 980 | [12] | |
RW Cygni | 980 | [12] | |
GCIRS 7 | 960 | [18] | |
Antares A (Alpha Scorpii A) | 883 | ||
Theta Muscae | 878 | ||
V602 Carinae | 860 | [12] | |
V1749 Cygni | 830 | [12] | |
IX Carinae | 790 | [12] | |
SU Persei | 780 | In the Perseus Double Cluster | [12] |
TV Geminorum | 770 | [12] | |
T Cephei | 742 | ||
V382 Carinae | 700 | Yellow hypergiant, one of the rarest types of star. |
Star name | Solar radii (Sun = 1) |
Notes | Ref. |
---|---|---|---|
V509 Cassiopeiae | 650 | Yellow hypergiant, one of the rarest types of a star. | |
TZ Cassiopeiae | 645 | ||
CE Tauri ("Ruby Star") | 608 | Can be occulted by the Moon, allowing accurate determination of its apparent diameter. | [19] |
V355 Cephei | 535 | [9][12] | |
R Leporis ("Hind's Crimson Star") | 500 | One of the largest carbon stars existent in the Milky Way. | |
Alpha Herculis (Ras Algethi) | 460 | ||
Rho Cassiopeiae | 450 | A yellow hypergiant, one of the rarest types of a star. | |
Mira A (Omicron Ceti) | 400 | Prototype Mira variable | [20] |
V838 Monocerotis | 380 | Once topped to the list as one of the largest known stars, after experiencing a nova outburst it gradually decreased in size. | |
R Doradus | 370 | Star with the second largest apparent size after the Sun. | |
The Pistol Star | 306 | Blue hypergiant, among the most massive and luminous stars known. | |
Eta Carinae A (Tseen She) | 240 | Previously thought to be the most massive single star, but in 2005 it was realized to be a binary system | [21] |
S Doradus | 240 | Prototype S Doradus variable | |
La Superba (Y Canum Venaticorum) | 215 | One of the coolest and reddest known stars. | |
Deneb (Alpha Cygni) | 203 | 19th brightest star in the night sky. | |
Peony Nebula Star | 100 | Candidate for most luminous star in the Milky Way. | |
Rigel A (Beta Orionis A) | 78 | Seventh brightest star in the night sky. | |
Canopus (Alpha Carinae) | 65 | Second brightest star in the night sky. | |
Aldebaran (Alpha Tauri) | 44.2 | [22] | |
R136a1 | 28.8 | Also on the list as the most massive and luminous star known. | |
HDE226868 | 21 | The supergiant companion of black hole Cygnus X-1. The black hole is 500,000 times smaller than the star. | |
VV Cephei B | 10 | The B-type main sequence companion of VV Cephei A. |
See also
- Constellation
- Lists of stars
- List of most massive stars
- List of most luminous stars
- List of hottest known stars
- List of most massive black holes
- TrES-4b, one of the largest known planets
References
- ^ Levesque, E. M.; Massey, P.; Olsen, K. A. G.; Plez, B.; Meynet, G.; Maeder, A. (2006). "The Effective Temperatures and Physical Properties of Magellanic Cloud Red Supergiants: The Effects of Metallicity". The Astrophysical Journal 645 (2): 1102. arXiv:astro-ph/0603596. Bibcode:2006ApJ...645.1102L. doi:10.1086/504417.
- ^ a b c Arroyo-Torres, B.; Wittkowski, M.; Marcaide, J. M.; Hauschildt, P. H. (2013). "The atmospheric structure and fundamental parameters of the red supergiants AH Scorpii, UY Scuti, and KW Sagittarii". Astronomy & Astrophysics 554: A76. doi:10.1051/0004-6361/201220920.
- ^ Zhang, B.; Reid, M. J.; Menten, K. M.; Zheng, X. W.; Brunthaler, A. (2012). "The distance and size of the red hypergiant NML Cygni from VLBA and VLA astrometry". Astronomy & Astrophysics 544: A42. arXiv:1207.1850. Bibcode:2012A&A...544A..42Z. doi:10.1051/0004-6361/201219587.
- ^ Humphreys, R. M. (1978). "Studies of luminous stars in nearby galaxies. I. Supergiants and O stars in the Milky Way". The Astrophysical Journal Supplement Series 38: 309. Bibcode:1978ApJS...38..309H. doi:10.1086/190559.
- ^ Davies, Ben; Kudritzki, Rolf-Peter; Figer, Donald F. (2010). "The potential of red supergiants as extragalactic abundance probes at low spectral resolution". Monthly Notices of the Royal Astronomical Society 407 (2): 1203. Bibcode:2010MNRAS.407.1203D. doi:10.1111/j.1365-2966.2010.16965.x.
- ^ Emily M. Levesque, Philip Massey, Bertrand Plez, and Knut A. G. Olsen (June 2009). "The Physical Properties of the Red Supergiant WOH G64: The Largest Star Known?". Astronomical Journal 137 (6): 4744. arXiv:0903.2260. Bibcode:2009AJ....137.4744L. doi:10.1088/0004-6256/137/6/4744.
- ^ Ohnaka, K.; Driebe, T.; Hofmann, K. H.; Weigelt, G.; Wittkowski, M. (2009). "Resolving the dusty torus and the mystery surrounding LMC red supergiant WOH G64". Proceedings of the International Astronomical Union 4: 454. doi:10.1017/S1743921308028858.
- ^ Wright, N. J.; Wesson, R.; Drew, J. E.; Barentsen, G.; Barlow, M. J.; Walsh, J. R.; Zijlstra, A.; Drake, J. J.; Eisloffel, J.; Farnhill, H. J. (16 October 2013). "The ionized nebula surrounding the red supergiant W26 in Westerlund 1". Monthly Notices of the Royal Astronomical Society: Letters 437 (1): L1–L5. arXiv:1309.4086. Bibcode:2014MNRAS.437L...1W. doi:10.1093/mnrasl/slt127.
- ^ a b c d Nicolas Mauron; Eric Josselin (2010). "The mass-loss rates of red supergiants and the de Jager prescription". arXiv:1010.5369 [astro-ph.SR].
- ^ Wittkowski, M.; Hauschildt, P. H.; Arroyo-Torres, B.; Marcaide, J. M. (2012). "Fundamental properties and atmospheric structure of the red supergiant VY Canis Majoris based on VLTI/AMBER spectro-interferometry". Astronomy & Astrophysics 540: L12. arXiv:1203.5194. Bibcode:2012A&A...540L..12W. doi:10.1051/0004-6361/201219126.
- ^ Choi, Yoon Kyung; Hirota, Tomoya; Honma, Mareki; Kobayashi, Hideyuki; Bushimata, Takeshi; Imai, Hiroshi; Iwadate, Kenzaburo; Jike, Takaaki; Kameno, Seiji; Kameya, Osamu; Kamohara, Ryuichi; Kan-Ya, Yukitoshi; Kawaguchi, Noriyuki; Kijima, Masachika; Kim, Mi Kyoung; Kuji, Seisuke; Kurayama, Tomoharu; Manabe, Seiji; Maruyama, Kenta; Matsui, Makoto; Matsumoto, Naoko; Miyaji, Takeshi; Nagayama, Takumi; Nakagawa, Akiharu; Nakamura, Kayoko; Oh, Chung Sik; Omodaka, Toshihiro; Oyama, Tomoaki; Sakai, Satoshi; et al. (2008). "Distance to VY CMa with VERA". Publications of the Astronomical Society of Japan (Publications Astronomical Society of Japan) 60 (5): 1007. arXiv:0808.0641. Bibcode:2008PASJ...60.1007C. doi:10.1093/pasj/60.5.1007.
- ^ a b c d e f g h i j k l m n o p q r s Levesque, E. M.; Massey, P.; Olsen, K. A. G.; Plez, B.; Josselin, E.; Maeder, A.; Meynet, G. (2005). "The Effective Temperature Scale of Galactic Red Supergiants: Cool, but Not as Cool as We Thought". The Astrophysical Journal 628 (2): 973. arXiv:astro-ph/0504337. Bibcode:2005ApJ...628..973L. doi:10.1086/430901.
- ^ o. Chesneau; a. Meilland; e. Chapellier; f. Millour; a.m. Van Genderen; y. Naze; n. Smith; a. Spang; et al. (2014). "The yellow hypergiant HR 5171 A: Resolving a massive interacting binary in the common envelope phase". Astronomy & Astrophysics. doi:10.1051/0004-6361/201322421.
- ^ Kusuno, K.; Asaki, Y.; Imai, H.; Oyama, T. (2013). "Distance and Proper Motion Measurement of the Red Supergiant, Pz Cas, in Very Long Baseline Interferometry H2O Maser Astrometry". The Astrophysical Journal 774 (2): 107. doi:10.1088/0004-637X/774/2/107.
- ^ Bibcode: 2014MNRAS.437..843G
- ^ Mohamed, S.; MacKey, J.; Langer, N. (2012). "3D simulations of Betelgeuse's bow shock". Astronomy & Astrophysics 541: A1. doi:10.1051/0004-6361/201118002.
- ^ Tsuji, Takashi (2000). "Water in Emission in the Infrared Space Observatory Spectrum of the Early M Supergiant Star μ Cephei". The Astrophysical Journal Letters 540 (2): 99–102. arXiv:astro-ph/0008058. Bibcode:2000ApJ...540L..99T. doi:10.1086/312879.
- ^ Paumard, T.; Pfuhl, O.; Martins, F.; Kervella, P.; Ott, T.; Pott, J.-U.; Le Bouquin, J. B.; Breitfelder, J.; Gillessen, S.; Perrin, G.; Burtscher, L.; Haubois, X.; Brandner, W. (2014). "GCIRS 7, a pulsating M1 supergiant at the Galactic centre. Physical properties and age". Astronomy & Astrophysics 568 (85): A85. arXiv:1406.5320. Bibcode:2014A&A...568A..85P. doi:10.1051/0004-6361/201423991.
- ^ "Big and Giant Stars". Retrieved 4 October 2014.
- ^ http://www.eso.org/~mwittkow/publications/conferences/SPIECWo5491199.pdf
- ^ "The HST Treasury Program on Eta Carinae". Etacar.umn.edu. 2003-09-01. Retrieved 2012-10-14.
- ^ Richichi, A.; Roccatagliata, V. (2005). "Aldebaran's angular diameter: how well do we know it?". Astronomy and Astrophysics 433: 305–312. arXiv:astro-ph/0502181. Bibcode:2005A&A...433..305R. doi:10.1051/0004-6361:20041765.
External links
- Giant Stars An interactive website comparing the Earth and the Sun to some of the largest known stars
- BBC News Three largest stars identified
- Universe Today What is the Biggest Star in the Universe?
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