GD 40

Last updated
GD 40
Observation data
Epoch J2000.0        Equinox J2000.0
Constellation Cetus
Right ascension 03h 02m 53.10375s [1]
Declination −01° 08 33.7987 [1]
Apparent magnitude  (V)15.56 [2]
Characteristics
Spectral type DB [2]
Astrometry
Parallax (π)15.3618 ± 0.0456  mas [1]
Distance 212.3 ± 0.6  ly
(65.1 ± 0.2  pc)
Absolute magnitude  (MV)11.30 [2]
Details
Mass 0.59 [3]   M
Radius 0.01?  R
Luminosity 0.0068 [2]   L
Surface gravity (log g)7.91 ± 0.18 [2]   cgs
Temperature 15300 [3]   K
Age 200 million  years
Other designations
GD 40, EGGR 384, US 3562, WD 0300-019
Database references
SIMBAD data

GD 40 is a white dwarf in the constellation Cetus. It is located about 212 light-years (65 parsecs) away from the Sun. [1] The star's spectrum has been found to show traces of external of metal contamination due to disruption of an extrasolar dwarf planet or an asteroid. [3] The disrupted object should have had roughly the same mass of the Solar System asteroid 3 Juno.

See also

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References

  1. 1 2 3 4 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. 1 2 3 4 5 Limoges, M.-M.; Bergeron, P. (2010). "A Spectroscopic Analysis of White Dwarfs in the Kiso Survey". The Astrophysical Journal. 714 (2): 1037–1051. arXiv: 1003.4313 . Bibcode:2010ApJ...714.1037L. doi:10.1088/0004-637X/714/2/1037. S2CID   118618131.
  3. 1 2 3 Klein; et al. (2010). "Chemical Abundances in the Externally Polluted White Dwarf GD 40: Evidence of a Rocky Extrasolar Minor Planet". The Astrophysical Journal. 709 (2): 950–962. arXiv: 0912.1422 . Bibcode:2010ApJ...709..950K. doi:10.1088/0004-637X/709/2/950. S2CID   118312133.