This is a list of exceptional white dwarf stars.
These were the first white dwarfs discovered fitting these conditions
Title | Star | Date | Data | Comments | Notes | Refs |
---|---|---|---|---|---|---|
First discovered | Sirius B | 1852 | Sirius system | Sirius B is also the nearest white dwarf (as of 2005) | [1] [2] | |
First found in a binary star system | ||||||
First double white dwarf system | LDS 275 | 1944 | L 462-56 system | [3] | ||
First solitary white dwarf | Van Maanen 2 | 1917 | Van Maanen's star is also the nearest solitary white dwarf | [4] | ||
First white dwarf with a planet | WD B1620−26 | 2003 | PSR B1620-26 b (planet) | This planet is a circumbinary planet, which circles both stars in the PSR B1620-26 system | [5] [6] | |
First singular white dwarf with a planet | WD 1145+017 | 2015 | WD 1145+017 b | Planet is extremely small and is disintegrating. | ||
First white dwarf that is a pulsar | AR Scorpii A | 2016 | The star is in a binary system with a red dwarf | [7] | ||
These are the white dwarfs which are currently known to fit these conditions
Title | Star | Date | Data | Comments | Notes | Refs |
---|---|---|---|---|---|---|
Nearest | Sirius | 1852 | 8.6 ly (2.6 pc ) | Sirius B is also the second white dwarf discovered. | [1] [2] | |
Farthest | SN UDS10Wil progenitor | 2013 | 10,000,000,000 ly z=1.914 | SN Wilson is a type-Ia supernova whose progenitor was a white dwarf | [8] [9] [10] | |
Oldest | WD 0343+247 SDSS J110217.48+411315.4 | 2012 | 12 Gy (tied) | |||
Youngest | SDSS J0003+0718 | 2011 | < 13 My | provisional estimate | ||
Highest surface temperature | RX J0439.8−6809 | 2015 | 250,000 K (250,000 °C ; 450,000 °F ) | This star is located in the Milky Way's galactic halo, in the field of the Large Magellanic Cloud | [11] [12] | |
Lowest surface temperature | LSPM J1403+4533 | 2010 | 2,670 K (2,400 °C ; 4,350 °F ) | Quite a large margin of error (1,500 K (1,230 °C; 2,240 °F)) | [13] | |
Most luminous | Z Andromedae B | 1,500 - 9,800 L☉ | [14] | |||
Least luminous | PSR J2222-0137 B | 2014 | too dim to observe | |||
Brightest apparent | Sirius | 1852 | 8.44 (V) | |||
Dimmest apparent | PSR J2222-0137 B | 2014 | too dim to observe | |||
Most massive (contender) | RE J0317-853 | 1998 | 1.35 M☉ | |||
Most massive (contender) | ZTF J1901+1458 [15] | 2020 | 1.35 M☉ | |||
Least massive | SDSS J091709.55+463821.8 | 2007 | 0.17 M☉ | |||
Largest | Z Andromedae B | 0.265±0.095 R☉ | ||||
Smallest | HD 49798 | 2021 | 0.0023 R☉ | [16] |
Star | Distance | Comments | Notes | Refs | |
---|---|---|---|---|---|
Sirius B | 8.58 ly (2.63 pc) | Sirius B is also the second white dwarf discovered. It is part of the Sirius system. | [1] [2] [17] [18] | ||
Procyon B | 11.43 ly (3.50 pc) | Part of Procyon system | [17] [18] | ||
van Maanen's Star | 14.04 ly (4.30 pc) | [17] [18] | |||
GJ 440 | 15.09 ly (4.63 pc) | [17] | |||
40 Eridani B | 16.25 ly (4.98 pc) | Part of 40 Eridani system | [17] [18] | ||
Stein 2051 B | 18.06 ly (5.54 pc) | Part of Stein 2051 system | [17] [18] | ||
LP 44-113 | 20.0 ly (6.1 pc) | [18] | |||
G 99-44 | 20.9 ly (6.4 pc) | [18] | |||
L 97-12 | 25.8 ly (7.9 pc) | [18] | |||
Wolf 489 | 26.7 ly (8.2 pc) | [18] | |||
A nova is a transient astronomical event that causes the sudden appearance of a bright, apparently "new" star that slowly fades over weeks or months. Causes of the dramatic appearance of a nova vary, depending on the circumstances of the two progenitor stars. All observed novae involve white dwarfs in close binary systems. The main sub-classes of novae are classical novae, recurrent novae (RNe), and dwarf novae. They are all considered to be cataclysmic variable stars.
A supernova is a powerful and luminous explosion of a star. A supernova occurs during the last evolutionary stages of a massive star or when a white dwarf is triggered into runaway nuclear fusion. The original object, called the progenitor, either collapses to a neutron star or black hole, or is completely destroyed to form a diffuse nebula. The peak optical luminosity of a supernova can be comparable to that of an entire galaxy before fading over several weeks or months.
A blue supergiant (BSG) is a hot, luminous star, often referred to as an OB supergiant. They have luminosity class I and spectral class B9 or earlier.
Delta Trianguli, Latinized from Delta Tri, is a spectroscopic binary star system approximately 35 light-years (11 pc) away in the constellation of Triangulum. The primary star is a yellow dwarf, while the secondary star is thought to be an orange dwarf. It has an apparent magnitude of +4.87 and forms an optical (line-of-sight) triple with Gamma Trianguli and 7 Trianguli.
Omicron Aquilae is the Bayer designation for a double star in the equatorial constellation of Aquila. The brighter component has an apparent visual magnitude of +5.11, which means it is faintly visible to the naked eye in dark suburban skies. The annual parallax shift of this star is 52.11 mas, which is equivalent to a physical distance of 62.6 light-years from Earth.
A Type Ia supernova is a type of supernova that occurs in binary systems in which one of the stars is a white dwarf. The other star can be anything from a giant star to an even smaller white dwarf.
SN 1994D was a Type Ia supernova event in the outskirts of galaxy NGC 4526. It was offset by 9.0″ west and 7.8″ south of the galaxy center and positioned near a prominent dust lane. It was caused by the explosion of a white dwarf star composed of carbon and oxygen. This event was discovered on March 7, 1994 by R. R. Treffers and associates using the automated 30-inch telescope at Leuschner Observatory. It reached peak visual brightness two weeks later on March 22. Modelling of the light curve indicates the explosion would have been visible around March 3-4. A possible detection of helium in the spectrum was made by W. P. S. Meikle and associates in 1996. A mass of 0.014 to 0.03 M☉ in helium would be needed to produce this feature.
Ross 548 is a white dwarf in the equatorial constellation of Cetus. With a mean apparent visual magnitude of 14.2 it is much too faint to be visible to the naked eye. Based on parallax measurements, it is located at a distance of 107 light years from the Sun. It was found to be variable in 1970 and in 1972 it was given the variable star designation ZZ Ceti. This is a pulsating white dwarf of the DAV type that is the prototype of the ZZ Ceti variable class., pp. 891, 895.
HD 115404 is a binary star system located in the constellation Coma Berenices. Parallax measurements made by Hipparcos put the system at 36 light-years, or 11 parsecs, away. The combined apparent magnitude of the system is 6.52, with the magnitudes of the components being 6.66 and 9.50.
Lambda Cephei is a fifth magnitude blue supergiant star in the constellation Cepheus, one of the hottest and most luminous visible to the naked eye.
SN UDS10Wil is a type Ia supernova, and as of April 2013, the farthest known. It has a redshift of 1.914, which strongly implies that it exploded when the universe was about a third of its current size. It was discovered with the Hubble Space Telescope's Wide Field Camera 3. The nickname SN Wilson is after the American President Woodrow Wilson.
GD 165 is a system of a white dwarf and a brown dwarf of spectral types DA4 + L4, located in constellation Boötes at approximately 103 light-years from Earth. GD 165 B remained the only brown dwarf companion of a white dwarf until the discovery of GD 1400 B, which was discovered 17 years later.
In astronomy, a calcium-rich supernova is a subclass of supernovae that, in contrast to more well-known traditional supernova classes, are fainter and produce unusually large amounts of calcium. Since their luminosity is located in a gap between that of novae and other supernovae, they are also referred to as "gap" transients. Only around 15 events have been classified as a calcium-rich supernova – a combination of their intrinsic rarity and low luminosity make new discoveries and their subsequent study difficult. This makes calcium-rich supernovae one of the most mysterious supernova subclasses currently known.
NGC 4242 is a spiral galaxy in the northern constellation of Canes Venatici. The galaxy is about 18 million light years away. It was discovered on 10 April 1788 by William Herschel, and it was described as "very faint, considerably large, irregular, round, very gradually brighter in the middle, resolvable" by John Louis Emil Dreyer, the compiler of the New General Catalogue.
Ross 640 is a white dwarf star in the northern constellation of Hercules, positioned near the constellation border with Corona Borealis. With an apparent visual magnitude of 13.83, it is too faint to be visible to the naked eye. Its trigonometric parallax from the Gaia mission is 62.9″, corresponding to a distance of 52 light-years.
2MASS J11263991−5003550(2MASS J1126−5003) is a brown dwarf about 53 light-years distant from earth. The brown dwarf is notable for an unusual blue near-infrared color. This brown dwarf does not show subdwarf features and the blue color cannot be explained by an unresolved binary. Instead the blue color is explained by patchy clouds. The patchy cloud model allows thick clouds and a cloud coverage of 50% to explain the spectra of 2MASS J1126−5003. Other blue L-dwarfs exist, but are quite rare.
HD 46588 is a star in the northern circumpolar constellation Camelopardalis. It has an apparent magnitude of 5.44, allowing it to be faintly seen with the naked eye. The object is relatively close at a distance of only 59 light years but is receding with a heliocentric radial velocity of 15 km/s.