List of star extremes

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UY Scuti (the brightest star in the image), as seen by the Rutherford Observatory. UY Scuti is the most voluminous star known as of now.

A star is a sphere that is mainly composed of hydrogen and plasma, held together by gravity and is able to produce light through nuclear fusion. Stars exhibit many diverse properties, resulting from different masses, volumes, velocities, stage in stellar evolution and even proximity to earth. Some of these properties are considered extreme and sometimes disproportionate by astronomers.

Age and distance[edit]

Title Object Date Data Comments Notes Refs See more
Nearest star Sun 3rd century BC 1 AU Our local star's distance was first determined in the 3rd century BC by Aristarchus of Samos Reported for reference
Second-nearest star Proxima Centauri 1915 1.30 pc Also called Alpha Centauri C, it is the outlying star in a trinary star system. This is currently the nearest known neighbouring star to our own Sun. This star was discovered in 1915, and its parallax was determined at the time, when enough observations were established. [NB 1] [1][2] List of nearest stars
Most distant individually seen star MACS J1149 Lensed Star 1 (or Icarus (star)) 2018 z=1.49
9.0 Gly
[3][4][5][6] List of the most distant astronomical objects
Most distant star Stars in UDFj-39546284 2011 z=11.9 List of the most distant astronomical objects
Oldest star HD 140283 14.5±0.8 billion years the "Methuselah star" [7] List of oldest stars
Youngest Stars are being formed constantly in the universe so it is impossible to tell which star is the youngest. For information on the properties of newly formed stars, See Protostar, Young Stellar Object and Star Formation.
Nearest stars by type
Title Object Date Data Comments Notes Refs See more
Nearest "average" star Alpha Centauri
A & B
1839 1.34 parsecs (4.4 ly) This was the third star whose parallax was determined. Before Alpha Cen, the record was held by 61 Cygni, the first star whose parallax was determined. [NB 1][NB 2][NB 3]
Nearest normal star Alpha Centauri C
(Proxima Centauri)
1915 1.30 parsecs (4.2 ly) Before Proxima, the title had been held by Alpha Centauri A&B. [NB 1][NB 3] [8][9]
Nearest red dwarf Before Proxima, the title had been held by Barnard's Star
Nearest degenerate star Sirius B 1852 8.6 light-years (2.6 pc) This is also the nearest white dwarf [NB 4]
Nearest borderline subgiant Procyon 11.5 light-years (3.5 pc) All stars closer to the Sun are either main sequence or dwarf stars.
Nearest undisputed subgiant delta Pavonis 19.9 light-years (6.1 pc) A subgiant, but only slightly brighter than the Sun.
Nearest "true" giant star Pollux 33.8 light-years (10.4 pc)
Nearest red giant Arcturus 36.7 light-years (11.3 pc)
Nearest spectral type A or hotter Sirius 8.6 light-years (2.6 pc)
Nearest neutron star RX J185635-3754 2000 400 light-years (120 pc) [10][11][12]
Nearest white dwarf Sirius B 1852 8.6 light-years (2.6 pc) Sirius B is also the first white dwarf discovered. [8][13]
Nearest flare star Proxima Centauri
(Alpha Centauri C)
1.30 parsecs (4.2 ly) α Cen C is also the nearest neighbouring star. [14]
Nearest brown dwarf Luhman 16 2013 6.5 light-years (2.0 pc) This is a pair of brown dwarfs in a binary system, with no other stars. [15]

Brightness and power[edit]

Title Object Date Data Comments Notes Refs See more
Brightest star Sun prehistoric m=−26.74 Reported for reference
[NB 5][NB 6]
Brightest star other than the Sun Sirius
(Alpha Canis Majoris)
prehistoric m=−1.46 [NB 5][NB 6][NB 7][NB 1] List of brightest stars
Brightest star in a transient event Progenitor of SN 1006 1006 m=−7.5 This was a supernova, and its remnant (SNR) is catalogued as PKS 1459-41 [NB 5][NB 6][NB 1] [16]
Dimmest star UDF 2457 [NB 5][NB 6]
Most luminous star R136a1 2010 V=−12.5 [NB 8] [17] List of most luminous stars
Most luminous star in a transient event Progenitor of GRB 080916C 2008 V=−40 The star exploded in a gamma-ray burst with the total energy equal to 9,000 supernovae [NB 8] List of gamma-ray bursts
Least luminous normal star 2MASS J0523-1403 2013 V=20.6 [NB 3][NB 8] [18]
Most energetic star R136a1 2010 B= [NB 9] [17]
Most energetic star in a transient event Progenitor of GRB 080916C 2008 [NB 9]
Least energetic normal star 2MASS J0523-1403 2013 L=0.000126LSun [NB 3][NB 9] [18]
Hottest normal star Melnick 34 T=~ 63000 K
Coolest normal star 2MASS J0523-1403 2013 T=2074K [18]
Title Object Date Data Comments Notes Refs See more
Hottest degenerate star KPD 0005+5106
H1504+65
2008
 
200000 K
200000 K
[19][20]
Hottest neutron star At least 100,000K
Hottest white dwarf KPD 0005+5106 2008 200000 K [21]
Hottest PG 1159 star/GW Vir star RX J2117+3412 1999 170000 K [22]
Coolest brown dwarf WISE 1828+2650 250–400 K WISE 0855-0714 may be cooler at 225–260 K, but its status as a rogue planet or sub-brown dwarf is not well known as its mass is between 3 and 10 MJ.

Size and mass[edit]

Title Object Date Data Comments Notes Refs See more
Largest apparent size star Sun prehistoric
(3rd century BCE)
31.6 – 32.7′ The apparent size of the Sun was first measured by Eratosthenes in the 3rd Century BCE,[23] who was the second person to measure the distance to the Sun. However, Thales of Miletus provided a measurement for the real size of the Sun in the 6th century BCE, as ​1720 the great circle of the Sun (the orbit of the Earth)[24] Reported for reference
[NB 6]
Largest apparent size star other than the Sun R Doradus 1997 0.057" This replaced Betelgeuse as the largest, Betelgeuse having been the first star other than the Sun to have its apparent size measured. [NB 6][NB 1] [25]
Smallest apparent size star [NB 6]
Most voluminous star UY Scuti 2013 r=1,708 ± 192 R VY Canis Majoris was once the largest star with a radius of 1,800 R to 2,200 R[26] (up to 3,230 R by some estimates[27]). However in 2012, the improved measurements give the star a radius of only 1,420 ± 120 R. Westerlund 1-26 could be as large as 2,544 R, but is most likely to be "only" 1,530 R.[28] De Jager et al (1988) calculated an effective temperature of 3,000 K, which would indicate a radius of 2,160 R, comparable to Saturn's orbit.[29] [30] List of largest stars
Least voluminous normal star EBLM J0555-57Ab 2017 r=0.084 RSun [NB 3] [31][32][33] List of least voluminous stars
Most massive star R136a1 2010 315 MSun This exceeds the predicted limit of 150 solar masses, previously believed to be the limit of stellar mass, according to the leading star formation theories. [NB 10] [17] List of most massive stars
Least massive normal star VB 10 0.075 MSun [NB 3] List of least massive stars
Most massive stars by type
Title Object Date Data Comments Notes Refs See more
Most massive brown dwarf PPl 15 1996 80 MJupiter This is at the limit between brown dwarfs and red dwarfs.[34][35] [34][36][37][38]
Most massive degenerate star The most massive type of degenerate star is the neutron star. See Most massive neutron star for this recordholder. [NB 4]
Most massive neutron star PSR J0348+0432 2013 2.01 MSun This millisecond pulsar greatly exceeds the predicted limit of neutron star size of roughly 1.5 solar masses. The previous titleholder had slightly less mass, at 1.97 solar masses. [39] Black Widow Pulsar
Most massive white dwarf RE J0317-853 1998 1.35 MSun [40][41]
Least massive stars by type
Title Object Date Data Comments Notes Refs See more
Least massive degenerate star The least massive type of degenerate star is the white dwarf. See Least massive white dwarf for this recordholder. [NB 4]
Least massive neutron star
Least massive white dwarf SDSS J091709.55+463821.8
(WD J0917+4638)
2007 0.17 MSun [42][43][44][45]
Least massive brown dwarf Jupiter(disputed) Antiquity 1 MJupiter Largest possible degenerate object by diameter. Would qualify as a sub brown dwarf, based on mass.

Motion[edit]

Title Object Date Data Comments Notes Refs See more
Highest proper motion Barnard's Star 10.3 "/yr This is also the fourth closest star to the Solar System. [46][47]
Lowest proper motion
Highest radial velocity
Lowest radial velocity
Highest peculiar motion
Lowest peculiar motion
Highest rotational speed of a normal star VFTS 102 2013 600 km/s [NB 3] [48]
Lowest rotational speed

Star systems[edit]

Title Object Date Data Comments Notes Refs See more
Least stars in a star system There are many single star systems.
Most stars in a star system Septuple star system Both are called 7-star systems in the 1997 MSC,[49] and appear in the 2008 MSC.[50] [NB 11] [49][50]
Stars in the closest orbit around one another There are many stars that are in contact binary systems (where two or more stars are in physical contact with each other).
Stars in the most distant orbit around one another HD 134439/HD 134440 0.56±0.25 light-years Orbit is most likely unstable long-term [NB 11]
Nearest multiple star system Alpha Centauri 1839 1.30 parsecs (4.2 ly) This was one of the first three stars to have its distance measured.[51][52] [8][53]
Nearest binary star system Luhman 16 2013 1.998 parsecs (6.52 ly) Brown dwarf binary system. The nearest non-brown dwarf binary is Sirius, and the nearest composed entirely of main-sequence stars is Luyten 726-8.
Nearest trinary star system Alpha Centauri 1839 1.38 parsecs (4.5 ly) Also nearest multiple star system, and nearest star system of any type
Nearest quaternary star system Gliese 570 5.88 parsecs (19.2 ly) K4 star orbited by a pair of M stars, all orbited by a T7 brown dwarf.
Nearest quintenary star system V1054 Ophiuchi 6.46 parsecs (21.1 ly) M3 star orbited by a pair of pair of M4 stars, together orbited by an M3.5 star, all orbited by an M7 star.
Nearest sextenary star system Castor 1718 15.6 parsecs (51 ly) A1 star orbited by a red dwarf, both orbited by another A star orbited by a red dwarf, all orbited by two red dwarfs orbiting each other.
Nearest septenary star system Nu Scorpii 150 parsecs (490 ly) A B3V star orbited by an unknown star, both orbited by another unknown star, together orbited by another unknown star, all orbited by a B9III star orbiting a pair of stars which are a B9III and unknown star.
Nearest octenary star system None known yet
Star systems by type
Title Object Date Data Comments Notes Refs See more
Shortest period black hole binary system MAXI J1659-152 2013 2.4 hours This exceeds the preceding recordholder by about one hour (Swift J1753.5-0127 with a 3.2 hour period) [54]

See also[edit]

Notes[edit]

  1. ^ a b c d e f Other than the Sun
  2. ^ An "average" star is a normal star which is larger than a red dwarf, but smaller than a giant star. Depending on the definition, this can also be called "Sun-like star".
  3. ^ a b c d e f g A normal star is a star that is past its protostar period, in its main fusion period, before becoming a degenerate star, black hole, or post-stellar nebula, and is not a failed star (brown dwarf).
  4. ^ a b c Not including stellar-mass black holes, or exotic stars
  5. ^ a b c d By visual magnitude (m)
  6. ^ a b c d e f g This is the appearance in the sky from Earth.
  7. ^ This does not include brightest stars due to outbursts
  8. ^ a b c Luminosity here represents how bright a star is if all stars were equally far away, in visible light.
  9. ^ a b c Energetic here is the total electromagnetic energy emitted by a star in all wavelengths.
  10. ^ Not including stellar black holes
  11. ^ a b The allowable distance between components of a star system is debated.

References[edit]

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