G 99-47

G 99-47

A visual band light curve for V1201 Orionis, adapted from Brinkworth et al. (2013)
Observation data
Epoch J2000      Equinox ICRS
Constellation Orion
Right ascension 05h 56m 25.45999s
Declination +05° 21′ 48.4432″
Apparent magnitude (V) 14.105
Characteristics
Spectral type DAP8.9
Apparent magnitude (B) 14.69
Apparent magnitude (V) 14.10
Apparent magnitude (R) 14.0
Apparent magnitude (I) 13.6
Apparent magnitude (J) 12.930 ± 0.022
Apparent magnitude (H) 12.720 ± 0.025
Apparent magnitude (K) 12.653 ± 0.024
Astrometry
Radial velocity (Rv)−414.02±10.41 km/s
Proper motion (μ) RA: -444.685 mas/yr
Dec.: -925.140 mas/yr
Parallax (π)123.1989±0.0170 mas
Distance26.474 ± 0.004 ly
(8.117 ± 0.001 pc)
Absolute magnitude (MV)14.59
Details
Mass0.71 ± 0.03 M☉
Radius0.011 R☉
Surface gravity (log g)8.20 ± 0.05 cgs
Temperature5790 ± 110 K
Age3.97 Gyr
Other designations
V1201 Ori, GJ 1087, EGGR 290, G 99-47, G 102-40, G 106-15, LHS 212, LTT 17891, NLTT 15834, WD 0553+053, 2MASS J05562547+0521486, USNO-B1.0 0953-00073703
Database references
SIMBADdata

G 99-47 (V1201 Orionis, EGGR 290) is a nearby degenerate star (white dwarf) of spectral class DAP8 (DAP8.9, or DAP8.7), the single known component of the system, located in the constellation Orion. G 99-47 is the 10th-closest known white dwarf, the next closest after LP 658-2 and GJ 3991 B.

The mass of G 99-47 is 0.71±0.03 Solar masses; its surface gravity is 108.20 ± 0.05 (1.58 · 108) cm·s−2, or approximately 162 000 of Earth's, corresponding to a radius 7711 km, or 121% of Earth's. Its temperature is 5790 ± 110 K, almost like the Sun's; its cooling age, i. e. age as degenerate star (not including lifetime as main sequence star and as giant star) is 3.97 Gyr. Due almost equal to the Sun's temperature, GJ 1087 should appear almost the same white color as the Sun. The white dwarf has a strong magnetic field, with measured vertical component near surface equal to 560 T.

Close approach to the Sun

In about 19,000 years, G 99-47 will have its closest approach to the Sun at a distance of about 2.5 light years.

See also

Notes

  1. ↑ From apparent magnitude and parallax.
  2. ↑ From surface gravity and mass.
  3. ↑ White dwarf cooling age, i. e. age as degenerate star (not including lifetime as main sequence star and as giant star)

References

  1. ↑ Brinkworth, Carolyn S.; Burleigh, Matthew R.; Lawrie, Katherine; Marsh, Thomas R.; Knigge, Christian (August 2013). "Measuring the Rotational Periods of Isolated Magnetic White Dwarfs". The Astrophysical Journal. 773 (1): 47. Bibcode:2013ApJ...773...47B. doi:10.1088/0004-637X/773/1/47. hdl:2381/37593. S2CID 56285149.
  2. 1 2 3 4 5 6 Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
  3. 1 2 3 4 5 6 7 8 9 10 Holberg, J. B.; Sion; Oswalt; McCook; Foran; Subasavage (2008). "A New Look at the Local White Dwarf Population". The Astronomical Journal. 135 (4): 1225–1238. Bibcode:2008AJ....135.1225H. doi:10.1088/0004-6256/135/4/1225. S2CID 122855486.
  4. 1 2 3 4 Sion, Edward M.; Holberg; Oswalt; McCook; Wasatonic (2009). "The White Dwarfs within 20 Parsecs of the Sun: Kinematics and Statistics". The Astronomical Journal. 138 (6): 1681–1689. arXiv:0910.1288. Bibcode:2009AJ....138.1681S. doi:10.1088/0004-6256/138/6/1681. S2CID 119284418.
  5. 1 2 3 4 5 6 7 8 "V* V1201 Ori -- White Dwarf". Centre de Données astronomiques de Strasbourg. Retrieved 2011-11-01.
  6. ↑ Yale Trigonometric Parallaxes, Fourth Edition (van Altena+ 1995)
  7. ↑ Reylé, Céline; Jardine, Kevin; Fouqué, Pascal; Caballero, Jose A.; Smart, Richard L.; Sozzetti, Alessandro (30 April 2021). "The 10 parsec sample in the Gaia era". Astronomy & Astrophysics. 650: A201. arXiv:2104.14972. Bibcode:2021A&A...650A.201R. doi:10.1051/0004-6361/202140985. S2CID 233476431. Data available at https://gruze.org/10pc/ Archived 12 March 2023 at the Wayback Machine
  8. ↑ Bagnulo, Stefano; Landstreet, John D. (2020), "Discovery of six new strongly magnetic white dwarfs in the 20 pc local population", Astronomy & Astrophysics, 643: A134, arXiv:2010.05795, Bibcode:2020A&A...643A.134B, doi:10.1051/0004-6361/202038565, S2CID 222290583
  9. ↑ Fernandez-Puig, Eloi; Morales, Juan Carlos; Laguna-Miralles, Júlia; Guijosa, Pol. "Stellar encounters in the solar neighbourhood and the special case of GJ~710". arXiv. Retrieved 19 July 2026.