GD 40

GD 40

Observation data Epoch J2000.0      Equinox J2000.0
Constellation	Cetus
Right ascension	03^h 02^m 53.10375^s[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[2]
Mass	0.54 M☉
Radius	0.014 ± 0.003 [a] R☉
Luminosity	0.0068 L☉
Surface gravity (log g)	7.91 ± 0.18 cgs
Age	200 Myr
Other designations
GD 40, EGGR 384, US 3562, WD 0300-013
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 hada at least the same mass of the asteroid 4 Vesta.

See also

• ZZ Piscium
• GD 61, white dwarf with an observed asteroid

Notes

1. Derived from known mass and gravity of star; radius is consistent with known luminosity and temperature within 0.4%.

References

1. 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. 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. 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.