HD 111232 is a star in the southern constellation of Musca. It is too faint to be visible with the naked eye, having an apparent visual magnitude of 7.59.[2] The distance to this star is 94.5 light years based on parallax.[1] It is drifting away from the Sun with a radial velocity of +104 km/s,[2] having come to within 14.1 light-years some 264,700 years ago.[9] The absolute magnitude of this star is 5.25,[2] indicating it would have been visible to the naked eye at that time.

HD 111232
Observation data
Epoch J2000      Equinox J2000
Constellation Musca
Right ascension 12h 48m 51.75258s[1]
Declination −68° 25′ 30.5471″[1]
Apparent magnitude (V) 7.59[2]
Characteristics
Spectral type G8 V Fe-1.0[3]
B−V color index 0.701±0.003[2]
Astrometry
Radial velocity (Rv)104.53±0.13[4] km/s
Proper motion (μ) RA: 27.283±0.021[4] mas/yr
Dec.: 112.918±0.024[4] mas/yr
Parallax (π)34.6094 ± 0.0239 mas[4]
Distance94.24 ± 0.07 ly
(28.89 ± 0.02 pc)
Absolute magnitude (MV)5.25[2]
Details[5]
Mass0.80±0.02 M
Radius0.88±0.01 R
Luminosity0.700±0.003 L
Surface gravity (log g)4.45±0.02 cgs
Temperature5,648±30 K
Metallicity [Fe/H]−0.32[6] dex
Rotation30.7 d[7]
Rotational velocity (v sin i)0.421[6] km/s
Age11.7±1.4 Gyr
Other designations
CPD−67°2079, Gaia DR2 5855730584310531200, HD 111232, HIP 62534, 2MASS J12485177-6825304[8]
Database references
SIMBADdata

This is an ancient, thick disk population II[10][7] star with an estimated age of twelve billion years.[5] It is a G-type main-sequence star with a stellar classification of G8 V Fe-1.0,[3] indicating an anomalous underabundance of iron in the stellar atmosphere. The star has 80% of the mass of the Sun and 88% of the Sun's radius. It is spinning slowly with a projected rotational velocity of 0.4 km/s.[6] X-ray emission has not been detected, suggesting a low level of coronal activity.[11][12] The star is radiating 70% of the luminosity of the Sun from its photosphere at an effective temperature of 5,648 K.[5]

Planetary system

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A superjovian planetary companion was detected by the CORALIE team, based on observations beginning in 2003.[7][12] Planets around such metal-poor stars are rare (the only two known similar cases as of 2019 are HD 22781 and HD 181720).[13] An astrometric measurement of the planet's inclination and true mass was published in 2022 as part of Gaia DR3.[14] Later in 2022, these parameters were revised along with the detection of a second substellar companion, likely a brown dwarf.[15]

The HD 111232 planetary system[15]
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(years)
Eccentricity Inclination Radius
b 7.965+1.128
−0.479
 MJ
2.148+0.088
−0.097
3.201+0.002
−0.001
0.214+0.005
−0.003
93.521+16.622
−18.063
°
c 18.063+4.209
−1.612
 MJ
17.250+2.158
−2.151
72.478+14.115
−12.341
0.558+0.027
−0.028
87.902+13.916
−22.591
°

References

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  1. ^ a b c 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. ^ a b c d e f 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.
  3. ^ a b Gray, R. O.; et al. (2003). "Contributions to the Nearby Stars (NStars) Project: Spectroscopy of Stars Earlier than M0 within 40 Parsecs: The Northern Sample. I". The Astronomical Journal. 126 (4): 2048. arXiv:astro-ph/0308182. Bibcode:2003AJ....126.2048G. doi:10.1086/378365. S2CID 119417105.
  4. ^ a b c d 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.
  5. ^ a b c Bonfanti, A.; Ortolani, S.; Piotto, G.; Nascimbeni, V. (2015). "Revising the ages of planet-hosting stars". Astronomy and Astrophysics. 575: A18. arXiv:1411.4302. Bibcode:2015A&A...575A..18B. doi:10.1051/0004-6361/201424951. S2CID 54555839.
  6. ^ a b c Soto, M. G.; Jenkins, J. S. (July 2018). "Spectroscopic Parameters and atmosphEric ChemIstriEs of Stars (SPECIES). I. Code description and dwarf stars catalogue". Astronomy & Astrophysics. 615: 28. arXiv:1801.09698. Bibcode:2018A&A...615A..76S. doi:10.1051/0004-6361/201731533. S2CID 119107228. A76.
  7. ^ a b c Mayor, M.; et al. (2004). "The CORALIE survey for southern extra-solar planets XII. Orbital solutions for 16 extra-solar planets discovered with CORALIE". Astronomy and Astrophysics. 415 (1): 391–402. arXiv:astro-ph/0310316. Bibcode:2004A&A...415..391M. doi:10.1051/0004-6361:20034250. S2CID 5233877.
  8. ^ "HD 111232". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2018-07-13.
  9. ^ Bailer-Jones, C.A.L.; Rybizki, J; Andrae, R.; Fouesnea, M. (2018). "New stellar encounters discovered in the second Gaia data release". Astronomy & Astrophysics. 616: A37. arXiv:1805.07581. Bibcode:2018A&A...616A..37B. doi:10.1051/0004-6361/201833456. S2CID 56269929.
  10. ^ Fuhrmann, Klaus; Chini, Rolf (January 2019). "On ancient solar-type stars". Monthly Notices of the Royal Astronomical Society. 482 (1): 471–489. Bibcode:2019MNRAS.482..471F. doi:10.1093/mnras/sty2660.
  11. ^ Poppenhaeger, K.; et al. (June 2010). "Coronal properties of planet-bearing stars". Astronomy and Astrophysics. 515: 9. arXiv:1003.5802. Bibcode:2010A&A...515A..98P. doi:10.1051/0004-6361/201014245. S2CID 119260432. A98.
  12. ^ a b Minniti, Dante; et al. (March 2009). "Low-Mass Companions for Five Solar-Type Stars From the Magellan Planet Search Program". The Astrophysical Journal. 693 (2): 1424–1430. arXiv:0810.5348. Bibcode:2009ApJ...693.1424M. doi:10.1088/0004-637X/693/2/1424. S2CID 119224845.
  13. ^ Adibekyan, Vardan (2019), "Heavy Metal Rules. I. Exoplanet Incidence and Metallicity", Geosciences, 9 (3): 105, arXiv:1902.04493, Bibcode:2019Geosc...9..105A, doi:10.3390/geosciences9030105, S2CID 119089419
  14. ^ Gaia Collaboration; et al. (2023). "Gaia Data Release 3". Astronomy & Astrophysics. 674: A34. arXiv:2206.05595. doi:10.1051/0004-6361/202243782. S2CID 249626026.
  15. ^ a b Feng, Fabo; Butler, R. Paul; et al. (August 2022). "3D Selection of 167 Substellar Companions to Nearby Stars". The Astrophysical Journal Supplement Series. 262 (21): 21. arXiv:2208.12720. Bibcode:2022ApJS..262...21F. doi:10.3847/1538-4365/ac7e57. S2CID 251864022.