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.[3] GG Lupi is located 1/2 degree (one full moon diameter) west of the 3rd magnitude star Delta Lupi.
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Lupus |
| Right ascension | 15h 18m 56.3747s[2] |
| Declination | −40° 47′ 17.597″[2] |
| Apparent magnitude (V) | 5.58 - 6.11[3] |
| Characteristics | |
| Spectral type | B7V (primary) B9V (secondary) |
| U−B color index | −0.46[4] |
| B−V color index | −0.099[4] |
| Variable type | Algol[3] |
| Astrometry | |
| Radial velocity (Rv) | +4.0±1.0[4] km/s |
| Proper motion (μ) | RA: −19.219[2] mas/yr Dec.: −21.791[2] mas/yr |
| Parallax (π) | 6.6639 ± 0.0894 mas[2] |
| Distance | 489 ± 7 ly (150 ± 2 pc) |
| Absolute magnitude (MV) | −0.53[5] |
| Orbit[4] | |
| Period (P) | 1.8495927 d |
| Semi-major axis (a) | 12.01 AU |
| Eccentricity (e) | 0.15 |
| Inclination (i) | 87.5° |
| Details | |
| Primary | |
| Mass | 4.16±0.12[4] M☉ |
| Radius | 2.42±0.05[4] R☉ |
| Surface gravity (log g) | 4.28[4] cgs |
| Temperature | 13,000[4] K |
| Rotational velocity (v sin i) | 97±8[6] km/s |
| Secondary | |
| Mass | 2.64±0.12[4] M☉ |
| Radius | 1.79±0.04[4] R☉ |
| Surface gravity (log g) | 4.30[4] cgs |
| Temperature | 10,600[4] K |
| Rotational velocity (v sin i) | 61±5[6] km/s |
| Age | 20[7] Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
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)[2] and proper motion make it a likely member of the Scorpius–Centaurus Association within the Gould's Belt star formation region.[4] 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.[7] Their orbit is somewhat eccentric (e=0.15) and the period of apsidal precession is 102 years.[11]
References
edit- ^ "MAST: Barbara A. Mikulski Archive for Space Telescopes". Space Telescope Science Institute. Retrieved 10 December 2022.
- ^ 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.
- ^ a b c "GG Lup". The International Variable Star Index. AAVSO. Retrieved 10 December 2022.
- ^ 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.
- ^ 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.
- ^ 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.
- ^ 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.
- ^ "V* GG Lup -- Eclipsing Binary". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2022-12-10.
- ^ 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.
- ^ 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.
- ^ 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.