GG Lupi

GG Lupi
Location of GG Lupi (circled in red)
Observation data
Epoch J2000      Equinox J2000
Constellation Lupus
Right ascension 15h 18m 56.3747s[1]
Declination −40° 47′ 17.597″[1]
Apparent magnitude (V) 5.58–6.11[2]
Characteristics
Spectral type B7V (primary) B9V (secondary)
U−B color index −0.46[3]
B−V color index −0.099[3]
Variable type Algol[2]
Astrometry
Radial velocity (Rv)+4.0±1.0[3] km/s
Proper motion (μ) RA: −19.219[1] mas/yr
Dec.: −21.791[1] mas/yr
Parallax (π)6.6639±0.0894 mas[1]
Distance489 ± 7 ly
(150 ± 2 pc)
Absolute magnitude (MV)−0.53[4]
Orbit[3]
Period (P)1.8495927 d
Semi-major axis (a)12.01 AU
Eccentricity (e)0.15
Inclination (i)87.5°
Details
Primary
Mass4.16±0.12[3] M
Radius2.42±0.05[3] R
Surface gravity (log g)4.28[3] cgs
Temperature13,000[3] K
Rotational velocity (v sin i)97±8[5] km/s
Secondary
Mass2.64±0.12[3] M
Radius1.79±0.04[3] R
Surface gravity (log g)4.30[3] cgs
Temperature10,600[3] K
Rotational velocity (v sin i)61±5[5] km/s
Age20[6] Myr
Other designations
HD 135876, HIP 74950, HR 5687, SAO 225647, 2MASS J15185637-4047176[7]
Database references
SIMBADdata

GG Lupi is an eclipsing binary star in the southern constellation of Lupus. Most of the time it is a magnitude 5.6 object, making it faintly visible to the naked eye, but during the primary eclipse its brightness falls to 6.1.[2] GG Lupi is located one half-degree (one full moon diameter) west of the third-magnitude star Delta Lupi.

This star was found to be a spectroscopic binary in 1930,[9] and its eclipses were detected in observations during 1964.[10] Its location in the sky, distance (~490 light-years)[1] and proper motion make it a likely member of the Scorpius–Centaurus association within the Gould's Belt star-formation region.[3] The two stars comprising this binary are both very young main-sequence stars of spectral type B. They are estimated to be about 20 million years old, placing them near the zero-age main sequence.[6] Their orbit is somewhat eccentric (e=0.15) and the period of apsidal precession is 102 years.[11]

References

  1. ^ a b c d e f 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.
  2. ^ a b c "GG Lup". The International Variable Star Index. AAVSO. Retrieved 10 December 2022.
  3. ^ a b c d e f g h i j k l m Budding, E.; Butland, R.; Blackford, M. (April 2015). "Absolute parameters of young stars: GG Lup and μ1 Sco". Monthly Notices of the Royal Astronomical Society. 448 (4): 3784–3796. arXiv:1502.04360. Bibcode:2015MNRAS.448.3784B. doi:10.1093/mnras/stv234.
  4. ^ Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters. 38 (5): 331. arXiv:1108.4971. Bibcode:2012AstL...38..331A. doi:10.1134/S1063773712050015. S2CID 119257644.
  5. ^ a b Marcussen, Marcus L.; Albrecht, Simon H. (2022). "The BANANA Project. VI. Close Double Stars are Well Aligned with Noticeable Exceptions; Results from an Ensemble Study Using Apsidal Motion and Rossiter-McLaughlin Measurements". The Astrophysical Journal. 933 (2): 227. arXiv:2112.00824. Bibcode:2022ApJ...933..227M. doi:10.3847/1538-4357/ac75c2. S2CID 244799745.
  6. ^ a b Andersen, J.; Clausen, J. V.; Gimenez, A. (October 1993). "Absolute dimensions of eclipsing binaries. XX. GG LUPI : young metal-deficient B stars". Astronomy and Astrophysics. 277: 439–451. Bibcode:1993A&A...277..439A.
  7. ^ "V* GG Lup -- Eclipsing Binary". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2022-12-10.
  8. ^ "MAST: Barbara A. Mikulski Archive for Space Telescopes". Space Telescope Science Institute. Retrieved 10 December 2022.
  9. ^ Neubauer, F. J. (August 1930). "Forty-two Spectroscopic Binary Stars". Publications of the Astronomical Society of the Pacific. 42 (248): 235. Bibcode:1930PASP...42..235N. doi:10.1086/124043. S2CID 121035980.
  10. ^ Smith, Lindsey F. (April 1966). "HR 5687: A New Eclipsing Binary". Publications of the Astronomical Society of the Pacific. 78 (462): 168. Bibcode:1966PASP...78..168S. doi:10.1086/128320. S2CID 120477301.
  11. ^ Wolf, M.; Zejda, M. (July 2005). "Apsidal motion in southern eccentric eclipsing binaries: V539 Ara, GG Lup, V526 Sgr and AO Vel". Astronomy and Astrophysics. 437 (2): 545–551. Bibcode:2005A&A...437..545W. doi:10.1051/0004-6361:20041868. S2CID 121307009.