List of most luminous stars
Encyclopedia
Below is a list of star
s arranged in order of decreasing luminosity
(increasing bolometric magnitude). Accurate measurement of stellar luminosities is quite difficult in practice, even when the apparent magnitude is measured accurately, for three reasons:
This list also cannot be complete because if a star is far enough away, observers on Earth will not be able to see it, no matter how high its luminosity may be.
Because of all these problems, other references may give very different lists of the most luminous stars (different ordering or different stars altogether). Data on different stars can be of somewhat different reliability, depending on the attention one particular star has received as well as largely differing physical difficulties in analysis (see the Pistol Star
for an example). The last stars in the list are familiar nearby stars put there for comparison, and not among the most luminous known. It may also interest the reader to know that The Sun is more luminous than approximately 95% of all known stars in the local neighborhood (out to, say, a few hundred light years), due to enormous numbers of somewhat less massive stars that are cooler and often much less luminous. For perspective, the overall range of stellar luminosities runs from dwarfs less than 1/10,000th as luminous as the Sun, to supergiants over 1,000,000 times more luminous.
Note that even the most luminous star
s are much less luminous than the more luminous persistent extragalactic objects, such as quasar
s. For example, 3C 273 has an average apparent magnitude
of 12.8 (when observing with a telescope
), but an absolute magnitude
of −26.7. If this object were 10 parsecs away it would appear nearly as bright in the sky as the Sun
(apparent magnitude −26.74). This quasar's luminosity
is, therefore, about 2 trillion (1012) times that of the Sun, or about 100 times that of the total light
of average large galaxies
like our Milky Way
. (Note that quasars often vary somewhat in luminosity.)
In terms of gamma rays, a magnetar
(type of neutron star
) called SGR 1806-20
, had an extreme burst reach Earth on 27 December 2004. It was the brightest event known to have impacted this planet
from an origin outside the Solar System
; if these gamma rays were visible, with an absolute magnitude
of approx. −29, it would be brighter than the Sun (as measured by the Swift
spacecraft).
The Gamma-ray burst GRB 971214
measured in 1998 was at the time thought to be the most energetic event in the universe
, with the equivalent energy of several hundred supernova
e. Later studies pointed out that the energy was probably the energy of one supernova which had been "beamed" towards Earth by the geometry of the surrounding gas.
Star
A star is a massive, luminous sphere of plasma held together by gravity. At the end of its lifetime, a star can also contain a proportion of degenerate matter. The nearest star to Earth is the Sun, which is the source of most of the energy on Earth...
s arranged in order of decreasing luminosity
Luminosity
Luminosity is a measurement of brightness.-In photometry and color imaging:In photometry, luminosity is sometimes incorrectly used to refer to luminance, which is the density of luminous intensity in a given direction. The SI unit for luminance is candela per square metre.The luminosity function...
(increasing bolometric magnitude). Accurate measurement of stellar luminosities is quite difficult in practice, even when the apparent magnitude is measured accurately, for three reasons:
- The distance d to the star must be known, to convert apparent to absolute magnitude. Absolute magnitude is the apparent magnitudeApparent magnitudeThe apparent magnitude of a celestial body is a measure of its brightness as seen by an observer on Earth, adjusted to the value it would have in the absence of the atmosphere...
a star would have if it were 10 parsecParsecThe parsec is a unit of length used in astronomy. It is about 3.26 light-years, or just under 31 trillion kilometres ....
s away from the viewer. Since apparent brightness decreases as the square of the distance (ie, as 1/d2), a small error (eg, 10%) in determining d implies an error ~2× as large (thus 20%) in luminosity. Stellar distances are only directly measured accurately out to d ~1000 lt-yrs. - The magnitudes at the wavelengths measured must be corrected for those not observed. "Absolute bolometric magnitude" (which term is redundant, practically speaking, since bolometric magnitudes are nearly always "absolute", i.e., corrected for distance) is a measure of the star's luminosity, summing over its emission at all wavelengths, and thus the total amount of energyEnergyIn physics, energy is an indirectly observed quantity. It is often understood as the ability a physical system has to do work on other physical systems...
radiated by a starStarA star is a massive, luminous sphere of plasma held together by gravity. At the end of its lifetime, a star can also contain a proportion of degenerate matter. The nearest star to Earth is the Sun, which is the source of most of the energy on Earth...
every secondSecondThe second is a unit of measurement of time, and is the International System of Units base unit of time. It may be measured using a clock....
. Bolometric magnitudes can only be estimated by correcting for unobserved portions of the spectrumElectromagnetic spectrumThe electromagnetic spectrum is the range of all possible frequencies of electromagnetic radiation. The "electromagnetic spectrum" of an object is the characteristic distribution of electromagnetic radiation emitted or absorbed by that particular object....
that have to be modeled, which is always an issue, and often a large correction. - Even the observed magnitudes must be corrected for the absorption or extinctionExtinction (astronomy)Extinction is a term used in astronomy to describe the absorption and scattering of electromagnetic radiation by matter between an emitting astronomical object and the observer. Interstellar extinction—also called Galactic extinction, when it occurs in the Milky Way—was first...
of intervening interstellar or circumstellar dust and gas. This correction can be enormous and difficult to determine precisely. For example, until accurate infraredInfrared astronomyInfrared astronomy is the branch of astronomy and astrophysics that studies astronomical objects visible in infrared radiation. The wavelength of infrared light ranges from 0.75 to 300 micrometers...
observations became possible ~50 years ago, the Galactic CenterGalactic CenterThe Galactic Center is the rotational center of the Milky Way galaxy. It is located at a distance of 8.33±0.35 kpc from the Earth in the direction of the constellations Sagittarius, Ophiuchus, and Scorpius where the Milky Way appears brightest...
region of The Milky WayThe Milky WayThe Milky Way is an amusement/theme park in Devon, near Clovelly.-Space:* The Cosmic Typhoon is Devon's largest rollercoaster. It takes about 1min 20secs to go around with a top speed of . Passengers must be over 1.2 m to ride....
was totally obscured to stellar observations, which had to be made in the opticalSpectrumA spectrum is a condition that is not limited to a specific set of values but can vary infinitely within a continuum. The word saw its first scientific use within the field of optics to describe the rainbow of colors in visible light when separated using a prism; it has since been applied by...
.
This list also cannot be complete because if a star is far enough away, observers on Earth will not be able to see it, no matter how high its luminosity may be.
Because of all these problems, other references may give very different lists of the most luminous stars (different ordering or different stars altogether). Data on different stars can be of somewhat different reliability, depending on the attention one particular star has received as well as largely differing physical difficulties in analysis (see the Pistol Star
Pistol Star
The Pistol Star is a blue hypergiant and is one of the most luminous known stars in the Milky Way Galaxy.It is one of many massive young stars in the Quintuplet cluster in the Galactic Center region....
for an example). The last stars in the list are familiar nearby stars put there for comparison, and not among the most luminous known. It may also interest the reader to know that The Sun is more luminous than approximately 95% of all known stars in the local neighborhood (out to, say, a few hundred light years), due to enormous numbers of somewhat less massive stars that are cooler and often much less luminous. For perspective, the overall range of stellar luminosities runs from dwarfs less than 1/10,000th as luminous as the Sun, to supergiants over 1,000,000 times more luminous.
Data
| Star name | Apparent visible magnitude |
Absolute bolometric magnitude |
Bolometric luminosity (solar units) |
|---|---|---|---|
| R136a1 R136a1 R136a1 is a blue hypergiant star and the most massive star known. It is an estimated 265 solar masses. The star is also the most luminous at 8,700,000 times the luminosity of the Sun.... (in LMC Large Magellanic Cloud The Large Magellanic Cloud is a nearby irregular galaxy, and is a satellite of the Milky Way. At a distance of slightly less than 50 kiloparsecs , the LMC is the third closest galaxy to the Milky Way, with the Sagittarius Dwarf Spheroidal and Canis Major Dwarf Galaxy lying closer to the center... ) |
12.77 | −12.5 | 8,700,000 |
| Cygnus OB2-12 Cygnus OB2-12 Cygnus OB2-12 is an extremely bright blue hypergiant with an absolute bolometric magnitude of -12.2, which approaches the upper limit believed possible for normal single stars.... |
11.4 | −12.2 | 6,300,000 |
| HD 93129A HD 93129A HD 93129A is one of the most luminous stars in the Milky Way. This very young blue hypergiant is an O-type hypergiant located about 7500 light-years from Earth in the bright nebula NGC 3372, the same nebula that harbors other super luminous stars, like Eta Carinae.HD 93129A is actually the brighter... |
6.97 | −12.1 | 5,500,000 |
| η Car | -0.8 to 7.9 | −12.0 | 5,000,000 |
| LBV 1806-20 (Middle Model) | 8.6 | −12.0 | 5,000,000 |
| QPM-241 QPM-241 QPM-241 is a Wolf–Rayet star in the Sagittarius constellation. It is the second brightest star in the Quintuplet cluster. With a luminosity of 4.500.000 solar units, it is also one of the most luminous stars.... |
−11.9 | 4,500,000 | |
| Pismis 24-1 Pismis 24-1 Pismis 24-1 is part of the open cluster Pismis 24 within the nebula NGC 6357 about 8150 light-years away. Pismis 24-1 is the largest and more brilliant of the visible stars of this cluster, and is one of the most massive and luminous stars known... |
10.43 | −11.8 | 4,200,000 |
| WR 101e | 13.1 | −11.6 | 3,700,000 |
| WR 102ka WR 102ka WR 102ka also known as the Peony Nebula Star or Peony star is a Wolf-Rayet star that is one of several candidates for the most luminous known star in our Milky Way Galaxy. Peony nebula star is a hypergiant luminous blue variable star... |
−11.6 | 3,700,000 | |
| HD 5980 HD 5980 HD 5980 is a binary star in NGC 346 nebula. It is one of the brightest stars in the Small Magellanic Cloud, and one of the most luminous stars known. HD 5980 A is probably a luminous blue variable of about 40–60 solar masses, while HD 5980 B is an evolved Wolf–Rayet star of about 30 solar masses.... |
11.52 | −11.5 | 3,400,000 |
| LSS 4067 | −11.4 | 3,000,000; | |
| HD 93250 HD 93250 HD 93250 is a blue main sequence star in cluster .... |
7.50 | −11.3 | 2,800,000; |
| Cygnus OB2-8 Cyg OB2 -8A Cyg OB2-8A or TYC 3161-01325-1 is a eclipsing binary in Cyg OB2 Association.HIC 101425 includes the components CCDM J20332+4119A, CCDM J20332+4119B, CCDM J20332+4119D and CCDM J20332+4119E.-References:... |
8.99 | −11.3 | 2,750,000 |
| Var 83 Var 83 Var 83 is a blue hypergiant in the constellation Triangulum, in the Triangulum Galaxy. With its bolometric luminosity of ±2,240,000 it is one of the most luminous stars known.... (in M33) |
16.40 | −11.1 | 2,240,000 |
| HDE 269810 (in LMC Large Magellanic Cloud The Large Magellanic Cloud is a nearby irregular galaxy, and is a satellite of the Milky Way. At a distance of slightly less than 50 kiloparsecs , the LMC is the third closest galaxy to the Milky Way, with the Sagittarius Dwarf Spheroidal and Canis Major Dwarf Galaxy lying closer to the center... ) |
12.28 | −11.1 | 2,200,000 |
| Wray 17-96 Wray 17-96 Wray 17-96 is a very luminous star in the Scorpius constellation, about away. Likely a luminous blue variable , it has an absolute bolometric magnitude of −10.9 , making it one of the most luminous stars known. Wray 17-96 is also notable for its gas hull, once thought to be a planetary nebula.... |
17.8 | −10.9 | 1,800,000 |
| The Pistol Star Pistol Star The Pistol Star is a blue hypergiant and is one of the most luminous known stars in the Milky Way Galaxy.It is one of many massive young stars in the Quintuplet cluster in the Galactic Center region.... (Low Model) |
−10.8 | 1,700,000 | |
| ζ1 Sco Zeta¹ Scorpii Zeta1 Scorpii is a B-type hypergiant star in the constellation of Scorpius. It has an apparent visual magnitude which varies between 4.66 and 4.86... |
4.66 to 4.86 | −10.8 | 1,700,000 |
| AF And (in M31) | −10.8 | 1,600,000 | |
| LY Aurigae LY Aurigae LY Aurigae is an eclipsing binary hypergiant of Beta Lyr type in the constellation Auriga.-References:* * * *... |
6.85 | −10.6 | 1,400,000 |
| Tr 27-27 | −10.5 | 1,350,000; | |
| Var B (in M33) | −10.4 | 1,100,000 | |
| AG Car AG Carinae AG Carinae is a star in the constellation Carina. It is classified as a luminous blue variable and is one of the most luminous stars in the Milky Way. The large distance and intervening dust mean that the star is not visible to the naked eye; its apparent brightness varies irregularly between... |
5.7 to 9.0 | −10.3 | 1,000,000 |
| S Dor S Doradus S Doradus is the brightest star in the Large Magellanic Cloud, a satellite of the Milky Way. A hypergiant, it is one of the most luminous stars known , but so far away that it is invisible to the naked eye.This star belongs to its own eponymous S Doradus class of variable stars S Doradus is the... |
8.6 to 11.5 (B) | −10.1 | 870,000 |
| Var C (in M33) | −9.8 | 660,000 | |
| 34 Cyg P Cygni P Cygni is a variable star in the constellation Cygnus. The designation "P" was originally assigned by Johann Bayer in Uranometria as a nova.... |
4.8 | −9.7 | 630,000 |
| ρ Cas Rho Cassiopeiae Rho Cassiopeiae is a yellow hypergiant star in the constellation Cassiopeia. It is about away from Earth, yet can still be seen by the naked eye , as it is 550,000 times as luminous as the Sun. On average, it has an absolute magnitude of −7.5, making it one of the most luminous stars known... |
4.1 to 6.2 | −9.6 | 550,000 |
| x Car V382 Carinae V382 Carinae, also known as x Carinae , is a star in the constellation Carina.V382 Carinae is a yellow G-type hypergiant with a mean apparent magnitude of +3.93. It is 5930.90 light years from Earth. It is classified as a Cepheid variable star and its brightness varies from magnitude +3.84 to... |
3.93 | −9.5 | 520,000 |
| HR Car HR Carinae HR Carinae is a supergiant, luminous blue variable star located in the constellation Carina. It is surrounded by a vast nebula of ejected nuclear-processed material because this star has a multiple shell expanding atmosphere. This star is among the most luminous stars in our galaxy... |
−9.5 | 500,000 | |
| Plaskett's Star Plaskett's star Plaskett's Star is a spectroscopic binary at a distance of around 6600 light-years... |
6.05 | −9.47 | 500,000 (high model) |
| DL Cru DL Crucis DL Crucis is a variable star in the constellation Crux.-References:*... |
6.24 | −9.47 | 500,000 |
| AE And (in M31) | −9.4 | 450,000 | |
| VY CMa VY Canis Majoris VY Canis Majoris is the largest known star and also one of the most luminous. Located in the constellation Canis Major, it is a red hypergiant, between 1800 and 2100 solar radii, 8.4–9.8 astronomical units in radius, about 3.0 billion km or 1.9 billion miles in diameter, and about 1.5 kiloparsecs ... |
6.5 to 9.6 | −9.4 | 450,000 |
| χ2 Ori | 4.65 | −9.3 | 420,000 |
| HDE 226868 | 8.9 | −9.25 | 390,000 |
| ε Ori Epsilon Orionis Alnilam is a large blue supergiant star in the constellation of Orion. Its Flamsteed designation is 46 Orionis.... |
1.70 | −9.2 | 380,000 |
| KW Sgr | 8.9 | −9.17 | 370,000 |
| ζ Pup Zeta Puppis Zeta Puppis is a star in the constellation of Puppis. It is also known by the traditional names Naos and Suhail Hadar in Arabic.... |
2.21 | −9.0 | 360,000 |
| V354 Cep V354 Cephei V354 Cephei is a red supergiant star located within the Milky Way. It is an irregular variable located approximately 9,000 light-years away from our Sun, and is currently considered one of the largest known stars, with a radius estimate of 1520 times that of the Sun, or 1,060,000,000 km... |
10.82 to 11.35 | −9.15 | 360,000 |
| RW Cep RW Cephei RW Cephei is an M-class red hypergiant star in the constellation Cepheus. One of the largest stars known, RW Cephei is estimated at 1650 solar radii. RW Cephei, while nearly as large as the orbit of Jupiter, is not as large as other stars in the constellation of Cephus, namely V354 Cephei and VV... |
6.52 | −9.11 | 350,000 |
| V509 Cas V509 Cassiopeiae V509 Cassiopeiae is a star in the constellation Cassiopeia.V509 Cassiopeiae is a yellow-white G-type hypergiant with a mean apparent magnitude of +5.10. It is at least 7800 light years from Earth. It is classified as a semiregular variable star and its brightness varies from magnitude +4.75 to... |
5.10 | −9.11 | 350,000 |
| μ Cep Mu Cephei Mu Cephei , also known as Herschel's Garnet Star, is a red supergiant star in the constellation Cepheus. It is one of the largest and most luminous stars known in the Milky Way... (the Garnet Star) |
4.04 | −9.08 | 340,000 |
| VV Cep VV Cephei VV Cephei, also known as HD 208816, is an eclipsing binary star system located in the constellation Cepheus, approximately 2,400 light years from Earth.Size, mass and luminosity estimates are all considerably uncertain due to insufficient knowledge of the Cephei star system: Professor Kaler writes... A |
4.91 | −9.0 | 315,000 |
| η CMa Eta Canis Majoris Eta Canis Majoris is a star in the constellation Canis Major. It has the traditional name Aludra.The name Aludra originates from the Arabic: عذرا al-‘aðrā "the virgin"... |
2.45 | 300,000 | |
| ν Aql Nu Aquilae Nu Aquilae is a star in the constellation Aquila.Nu Aquilae is a yellow-white F-type supergiant with an apparent magnitude of +4.64. It is at least 3000 light years from Earth and lies close to the celestial equator.-References:... |
4.69 | 300,000 | |
| WOH G64 WOH G64 WOH G64 is a red hypergiant in the Large Magellanic Cloud. With 2000 times the radius of the Sun, it is one of the largest known stars.The size of WOH G64 is estimated at 2,785,000,000 km, or 1,900-2,000 solar radii.-See also:... |
280,000 | ||
| KY Cyg KY Cygni KY Cygni is a red supergiant star located in the constellation Cygnus. It is one of the largest stars known, at about 1,420 or more times the Sun's diameter, and is also one of the most luminous, with about 300,000 or more times the Sun's luminosity... |
−8.84 | 270,000 | |
| θ1 Ori C | 5.13 | −8.6 | 220,000 |
| 6 Cas 6 Cassiopeiae 6 Cassiopeiae is an A type bright supergiant or hypergiant. It is about 25 times as massive as the Sun.... |
5.55 | 200,000 | |
| Betelgeuse Betelgeuse Betelgeuse, also known by its Bayer designation Alpha Orionis , is the eighth brightest star in the night sky and second brightest star in the constellation of Orion, outshining its neighbour Rigel only rarely... |
0.58 | 135,000 | |
| ζ Ori | 1.79 | −7.8 | 100,000 |
| VV Cep VV Cephei VV Cephei, also known as HD 208816, is an eclipsing binary star system located in the constellation Cepheus, approximately 2,400 light years from Earth.Size, mass and luminosity estimates are all considerably uncertain due to insufficient knowledge of the Cephei star system: Professor Kaler writes... B |
−7.8 | 100,000 | |
| The following well-known stars are provided for the purpose of comparison. | |||
| Rigel Rigel Rigel is the brightest star in the constellation Orion and the sixth brightest star in the sky, with visual magnitude 0.18... |
0.12 | −7.3 | 85,000 |
| Antares Antares Antares is a red supergiant star in the Milky Way galaxy and the sixteenth brightest star in the nighttime sky . Along with Aldebaran, Spica, and Regulus it is one of the four brightest stars near the ecliptic... |
0.92 | −7.2 | 66,000 |
| Deneb Deneb Deneb is the brightest star in the constellation Cygnus and one of the vertices of the Summer Triangle. It is the 19th brightest star in the night sky, with an apparent magnitude of 1.25. A blue-white supergiant, Deneb is also one of the most luminous nearby stars... |
1.25 | −6.95 | 54,000 |
| Canopus | −0.62 | −5.53 | 12,900 |
| Achernar Achernar Achernar , sometimes spelled Achenar, is the brightest star in the constellation Eridanus and the ninth-brightest star in the night sky. Of the top ten apparent brightest stars —Sirius, Canopus, Alpha Centauri, Arcturus, Vega, Capella, Rigel, Procyon, Achernar and Betelgeuse—Achernar is the hottest... |
0.46 | −4.05 | 3,300 |
| β Lyrae Beta Lyrae Beta Lyrae is a binary star system approximately 882 light-years away in the constellation Lyra. Beta Lyrae has the traditional name Sheliak , from الشلياق šiliyāq, the Arabic name of the constellation Lyra.Beta Lyrae is an eclipsing semi-detached binary system made up of a B7II primary star and... |
3.52 | −3.91 | 2,900 |
| Polaris Polaris Polaris |Alpha]] Ursae Minoris, commonly North Star or Pole Star, also Lodestar) is the brightest star in the constellation Ursa Minor. It is very close to the north celestial pole, making it the current northern pole star.... |
1.97 | −3.6 | 2,200 |
| Aldebaran Aldebaran Aldebaran is a red giant star located about 65 light years away in the zodiac constellation of Taurus. With an average apparent magnitude of 0.87 it is the brightest star in the constellation and is one of the brightest stars in the nighttime sky... |
0.85 | −0.63 | 350 |
| Arcturus | −0.04 | −0.31 | 210 |
| Capella Capella (star) Capella is the brightest star in the constellation Auriga, the sixth brightest star in the night sky and the third brightest star in the northern celestial hemisphere, after Arcturus and Vega. Although it appears to be a single star to the naked eye, it is actually a star system of four stars in... |
0.08 | 0.4 | 78.5 |
| Castor Castor (star) Castor is the second brightest star in the constellation Gemini and one of the brightest stars in the night sky. Although it has the Bayer designation "alpha", it is actually fainter than Beta Geminorum... |
1.98 | 0.5 | 50 |
| Vega Vega Vega is the brightest star in the constellation Lyra, the fifth brightest star in the night sky and the second brightest star in the northern celestial hemisphere, after Arcturus... |
0.00 | 0.58 | 37 |
| Sirius Sirius Sirius is the brightest star in the night sky. With a visual apparent magnitude of −1.46, it is almost twice as bright as Canopus, the next brightest star. The name "Sirius" is derived from the Ancient Greek: Seirios . The star has the Bayer designation Alpha Canis Majoris... |
−1.46 | 1.4 | 25.4 |
| α Centauri Alpha Centauri Alpha Centauri is the brightest star in the southern constellation of Centaurus... A |
−0.01 | 4.38 | 1.519 |
| Sun Sun The Sun is the star at the center of the Solar System. It is almost perfectly spherical and consists of hot plasma interwoven with magnetic fields... |
−26.74 | 4.83 | 1.00 |
Note that even the most luminous star
Star
A star is a massive, luminous sphere of plasma held together by gravity. At the end of its lifetime, a star can also contain a proportion of degenerate matter. The nearest star to Earth is the Sun, which is the source of most of the energy on Earth...
s are much less luminous than the more luminous persistent extragalactic objects, such as quasar
Quasar
A quasi-stellar radio source is a very energetic and distant active galactic nucleus. Quasars are extremely luminous and were first identified as being high redshift sources of electromagnetic energy, including radio waves and visible light, that were point-like, similar to stars, rather than...
s. For example, 3C 273 has an average apparent magnitude
Apparent magnitude
The apparent magnitude of a celestial body is a measure of its brightness as seen by an observer on Earth, adjusted to the value it would have in the absence of the atmosphere...
of 12.8 (when observing with a telescope
Telescope
A telescope is an instrument that aids in the observation of remote objects by collecting electromagnetic radiation . The first known practical telescopes were invented in the Netherlands at the beginning of the 1600s , using glass lenses...
), but an absolute magnitude
Absolute magnitude
Absolute magnitude is the measure of a celestial object's intrinsic brightness. it is also the apparent magnitude a star would have if it were 32.6 light years away from Earth...
of −26.7. If this object were 10 parsecs away it would appear nearly as bright in the sky as the Sun
Sun
The Sun is the star at the center of the Solar System. It is almost perfectly spherical and consists of hot plasma interwoven with magnetic fields...
(apparent magnitude −26.74). This quasar's luminosity
Luminosity
Luminosity is a measurement of brightness.-In photometry and color imaging:In photometry, luminosity is sometimes incorrectly used to refer to luminance, which is the density of luminous intensity in a given direction. The SI unit for luminance is candela per square metre.The luminosity function...
is, therefore, about 2 trillion (1012) times that of the Sun, or about 100 times that of the total light
Light
Light or visible light is electromagnetic radiation that is visible to the human eye, and is responsible for the sense of sight. Visible light has wavelength in a range from about 380 nanometres to about 740 nm, with a frequency range of about 405 THz to 790 THz...
of average large galaxies
Galaxy
A galaxy is a massive, gravitationally bound system that consists of stars and stellar remnants, an interstellar medium of gas and dust, and an important but poorly understood component tentatively dubbed dark matter. The word galaxy is derived from the Greek galaxias , literally "milky", a...
like our Milky Way
Milky Way
The Milky Way is the galaxy that contains the Solar System. This name derives from its appearance as a dim un-resolved "milky" glowing band arching across the night sky...
. (Note that quasars often vary somewhat in luminosity.)
In terms of gamma rays, a magnetar
Magnetar
A magnetar is a type of neutron star with an extremely powerful magnetic field, the decay of which powers the emission of copious high-energy electromagnetic radiation, particularly X-rays and gamma rays...
(type of neutron star
Neutron star
A neutron star is a type of stellar remnant that can result from the gravitational collapse of a massive star during a Type II, Type Ib or Type Ic supernova event. Such stars are composed almost entirely of neutrons, which are subatomic particles without electrical charge and with a slightly larger...
) called SGR 1806-20
SGR 1806-20
|- style="vertical-align: top;"| Distance | 50,000 light-years SGR 1806-20 is a magnetar, a particular type of neutron star. It has been identified as a soft gamma repeater. SGR 1806-20 is located about 14.5 kiloparsecs from Earth on the far side of our Milky Way galaxy in the constellation of...
, had an extreme burst reach Earth on 27 December 2004. It was the brightest event known to have impacted this planet
Planet
A planet is a celestial body orbiting a star or stellar remnant that is massive enough to be rounded by its own gravity, is not massive enough to cause thermonuclear fusion, and has cleared its neighbouring region of planetesimals.The term planet is ancient, with ties to history, science,...
from an origin outside the Solar System
Solar System
The Solar System consists of the Sun and the astronomical objects gravitationally bound in orbit around it, all of which formed from the collapse of a giant molecular cloud approximately 4.6 billion years ago. The vast majority of the system's mass is in the Sun...
; if these gamma rays were visible, with an absolute magnitude
Absolute magnitude
Absolute magnitude is the measure of a celestial object's intrinsic brightness. it is also the apparent magnitude a star would have if it were 32.6 light years away from Earth...
of approx. −29, it would be brighter than the Sun (as measured by the Swift
Swift Gamma-Ray Burst Mission
The Swift Gamma-Ray Burst Mission consists of a robotic spacecraft called Swift, which was launched into orbit on 20 November 2004, 17:16:00 UTC on a Delta II 7320-10C expendable launch vehicle. Swift is managed by the NASA Goddard Space Flight Center, and was developed by an international...
spacecraft).
The Gamma-ray burst GRB 971214
GRB 971214
GRB 971214 is a gamma-ray burst observed in 1997. It originated 12 billion light years away. For a brief period this was thought by some researchers to have been the most energetic event observed in the universe, but this claim has since been discredited.In 1998, it was hypothesized by George...
measured in 1998 was at the time thought to be the most energetic event in the universe
Universe
The Universe is commonly defined as the totality of everything that exists, including all matter and energy, the planets, stars, galaxies, and the contents of intergalactic space. Definitions and usage vary and similar terms include the cosmos, the world and nature...
, with the equivalent energy of several hundred supernova
Supernova
A supernova is a stellar explosion that is more energetic than a nova. It is pronounced with the plural supernovae or supernovas. Supernovae are extremely luminous and cause a burst of radiation that often briefly outshines an entire galaxy, before fading from view over several weeks or months...
e. Later studies pointed out that the energy was probably the energy of one supernova which had been "beamed" towards Earth by the geometry of the surrounding gas.
See also
- List of stars
- List of largest stars
- List of most massive stars
- List of brightest stars
- List of nearest stars
- Gamma ray burstGamma ray burstGamma-ray bursts are flashes of gamma rays associated with extremely energetic explosions that have been observed in distant galaxies. They are the most luminous electromagnetic events known to occur in the universe. Bursts can last from ten milliseconds to several minutes, although a typical...
- QuasarQuasarA quasi-stellar radio source is a very energetic and distant active galactic nucleus. Quasars are extremely luminous and were first identified as being high redshift sources of electromagnetic energy, including radio waves and visible light, that were point-like, similar to stars, rather than...