BD-11 4672

BD-11 4672
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Scutum[1]
Right ascension 18h 33m 28.832s[2]
Declination −11° 38′ 09.72″[2]
Apparent magnitude (V) 9.99±0.05[3]
Characteristics
Evolutionary stage main sequence[3]
Spectral type K7 V[4][3]
Apparent magnitude (B) 11.21±0.10[3]
Apparent magnitude (J) 7.651±0.023[1]
B−V color index 1.263±0.009[1]
Astrometry
Radial velocity (Rv)−87.515±0.0011[5] km/s
Proper motion (μ) RA: −288.440 mas/yr[2]
Dec.: −235.615 mas/yr[2]
Parallax (π)36.7534 ± 0.0157 mas[2]
Distance88.74 ± 0.04 ly
(27.21 ± 0.01 pc)
Details
Mass0.651+0.031
−0.029[3] M☉
Radius0.639+0.020
−0.022[3] R☉
Luminosity0.157+0.019
−0.017[3] L☉
Surface gravity (log g)4.642+0.027
−0.025[3] cgs
Temperature4,550±110[3] K
Metallicity [Fe/H]−0.48±0.07[6] dex
Rotation~25 d[3]
Rotational velocity (v sin i)1.0±0.5[3] km/s
Age7.4+4.5
−4.9[3] Gyr
Other designations
BD−11 4672, Gaia DR2 4154598526336121600, GJ 717, HIP 90979, PPM 234703, Wolf 1462, TYC 5699-2129-1, GSC 05699-02129, 2MASS J18332885-1138097[7]
Database references
SIMBADdata

BD−11 4672 is a single star with a pair of orbiting exoplanets in the southern constellation of Scutum, the shield. The designation BD−11 4672 comes from the Bonner Durchmusterung star catalogue, which was published during the nineteenth century in Germany. With an apparent visual magnitude of 9.99,[3] the star is much too faint to be viewed with the naked eye. It is located at a distance of 89 light years from the Sun, as determined from parallax,[2] but is drifting closer with a radial velocity of −87.5 km/s.[5] This was recognised as a high proper motion star by German astronomer Max Wolf in 1924[8] and is traversing the celestial sphere at an angular rate of 0.401 arcsec yr−1.[9]

The spectrum of BD−11 4672 matches a K-type main-sequence star, an orange dwarf, with a stellar classification of K7 V.[4] Its age is not well constrained, but is probably older than the Sun. It is a metal-poor star, showing an iron abundance that is 35% of solar.[6] No significant flare activity was detected.[10] The star shows evidence of a Sun-like magnetic activity cycle with a period of 7–10 years.[3] It has 65% of the mass and 64% of the radius of the Sun. The star is radiating 16% of the luminosity of the Sun from its photosphere at an effective temperature of 4,550 K.[3]

Planetary system

In 2010, a team of astronomers led by astronomer C. Moutou [fr] of the High Accuracy Radial Velocity Planet Searcher performed a radial-velocity analysis, which led to the suspicion of a gas giant exoplanet in orbit around BD−11 4672.[4] The existence of this exoplanet was confirmed in 2014.[11] In 2020, a second exoplanet was detected on an interior and much more eccentric orbit near the inner edge of the Star's habitable zone.[3]

The BD-11 4672 planetary system[12][3]
Companion
(in order from star) 		Mass Semimajor axis
(AU) 		Orbital period
(days) 		Eccentricity Inclination Radius
b >0.65±0.05 MJ 2.36±0.04 1634±14 0.05±0.05 — —
c >0.04836+0.009
−0.0066 MJ 		0.3±0.01 74.2±0.08 0.4±0.15 — —

See also

References

  1. ^ a b c 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.
  2. ^ a b c d e 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. ^ a b c d e f g h i j k l m n o p q Barbato, D.; et al. (2020), "The GAPS Programme at TNG XXIV. An eccentric Neptune-mass planet near the inner edge of the BD-11 4672 habitable zone", Astronomy & Astrophysics, A68: 641, arXiv:2006.14393, Bibcode:2020A&A...641A..68B, doi:10.1051/0004-6361/202037954, S2CID 220055727.
  4. ^ a b c Moutou, Claire; et al. (March 2011), "The HARPS search for southern extra-solar planets: XXVI: Seven new planetary systems", Astronomy & Astrophysics, 527, arXiv:1012.3830, Bibcode:2011A&A...527A..63M, doi:10.1051/0004-6361/201015371, S2CID 118696125, A63.
  5. ^ a b Soubiran, C.; et al. (2018), "Gaia Data Release 2. The catalogue of radial velocity standard stars", Astronomy and Astrophysics, 616: A7, arXiv:1804.09370, Bibcode:2018A&A...616A...7S, doi:10.1051/0004-6361/201832795, S2CID 52952408.
  6. ^ a b Andreasen, D. T.; et al. (2017), "SWEET-Cat update and FASMA A new minimization procedure for stellar parameters using high-quality spectra", Astronomy & Astrophysics, A69: 600, arXiv:1703.06671, Bibcode:2017A&A...600A..69A, doi:10.1051/0004-6361/201629967, S2CID 119534579.
  7. ^ "BD-11 4672". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2020-09-27.
  8. ^ Wolf, M.; Reinmuth, K. (1925), "Einige bewegte Sterne in Scutum", Astronomische Nachrichten, 223 (14): 231, Bibcode:1925AN....223..231W, doi:10.1002/asna.19242231404.
  9. ^ Luyten, W. J. (June 1995), "NLTT Catalogue (Luyten, 1979)", VizieR Online Data Catalog, Bibcode:1995yCat.1098....0L.
  10. ^ Lammer, H.; et al. (2020), "A census of Coronal Mass Ejections on solar-like stars", Monthly Notices of the Royal Astronomical Society, 493 (3): 4570–4589, arXiv:2002.04430, Bibcode:2020MNRAS.493.4570L, doi:10.1093/mnras/staa504, S2CID 211076125.
  11. ^ Moutou, C.; et al. (2014), "The HARPS search for southern extra-solar planets", Astronomy & Astrophysics, 576: A48, arXiv:1412.6591, Bibcode:2015A&A...576A..48M, doi:10.1051/0004-6361/201424965, S2CID 118512899.
  12. ^ "Planet BD-11 4672 b", exoplanet.eu, retrieved 2024-01-05.