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WD 1337+705
Observation data
Epoch J2000       Equinox J2000
Constellation Ursa Minor
Right ascension 13h 38m 50.4781s [1]
Declination +70° 17′ 07.6414″ [1]
Apparent magnitude (V) 12.773
Spectral type DA2.4 [2]
Proper motion (μ) RA: −402.093 ± 0.078 [1]  mas/ yr
Dec.: −24.608 ± 0.068 [1]  mas/ yr
Parallax (π)37.7083 ± 0.0422  mas [1]
Distance86.49 ± 0.10  ly
(26.52 ± 0.03  pc)
Absolute magnitude (MV)10.56 [2]
Mass0.59 [2]  M
Luminosity0.03 [3]  L
Temperature21290 K [2]  K
Other designations
WD 1337+705, EG 102, HIP 66578, LTT 18341
Database references

WD 1337+705 is a star in the constellation Ursa Minor. Shining with an apparent magnitude of 12.8, it is white dwarf 0.59 times as massive as the Sun. [2] It is 86.5 light-years distant from Earth. [1] It has 3% of the Sun's luminosity. [3]

In 1997, Jay Holberg and colleagues discovered magnesium in its spectrum, which suggests that it has some low mass companion or accretion of material happening as the star's temperature is not hot enough for its intrinsic emission. [4] Despite this, no direct evidence for a circumstellar disc, such as an infrared excess, has come to light. [5]


  1. ^ a b c d e f Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv: 1804.09365. Bibcode: 2018A&A...616A...1G. doi: 10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
  2. ^ a b c d e Gianninas, A.; Bergeron, P.; Ruiz, M. T. (2011). "A Spectroscopic Survey and Analysis of Bright, Hydrogen-rich White Dwarfs". The Astrophysical Journal. 743 (2): 27. arXiv: 1109.3171. Bibcode: 2011ApJ...743..138G. doi: 10.1088/0004-637X/743/2/138. 138.
  3. ^ a b Bannister, N. P.; Barstow, M. A.; Holberg, J. B.; Bruhweiler, F. C. (2003). "Circumstellar features in hot DA white dwarfs". Monthly Notices of the Royal Astronomical Society. 341 (2): 477–95. arXiv: astro-ph/0301204. Bibcode: 2003MNRAS.341..477B. doi: 10.1046/j.1365-8711.2003.06409.x.
  4. ^ Holberg, Jay; Barstow, M.A.; Green, Elizabeth M. (1997). "The Discovery of Mg II λ4481 in the White Dwarf EG 102: Evidence for Ongoing Accretion". The Astrophysical Journal. 474 (2): L127–L130. Bibcode: 1997ApJ...474L.127H. doi: 10.1086/310446.
  5. ^ Dickinson, N. J.; Barstow, M. A.; Welsh, B. Y.; Burleigh, M.; Farihi, J.; Redfield, S.; Unglaub, K. (2012). "The origin of hot white dwarf circumstellar features". Monthly Notices of the Royal Astronomical Society. 423 (2): 1397–1410. arXiv: 1203.5226. Bibcode: 2012MNRAS.423.1397D. doi: 10.1111/j.1365-2966.2012.20964.x.