HD 24040 is a star with two orbiting exoplanets in the equatorial constellation of Taurus. The star is too faint to be viewed with the naked eye, having an apparent visual magnitude of 7.50.[2] Based on parallax measurements, it is located at a distance of 152 light years. However, it is drifting closer to the Sun with a radial velocity of −9.4 km/s.[2]
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Taurus |
| Right ascension | 03h 50m 22.9678s[1] |
| Declination | +17° 28′ 34.9254″[1] |
| Apparent magnitude (V) | 7.50[2] |
| Characteristics | |
| Evolutionary stage | Main sequence |
| Spectral type | G2V[3] |
| B−V color index | 0.653±0.003[2] |
| Astrometry | |
| Radial velocity (Rv) | −9.36±0.08[2] km/s |
| Proper motion (μ) | RA: 113.433 mas/yr[1] Dec.: −251.101 mas/yr[1] |
| Parallax (π) | 21.4719 ± 0.0241 mas[1] |
| Distance | 151.9 ± 0.2 ly (46.57 ± 0.05 pc) |
| Absolute magnitude (MV) | 4.16[2] |
| Details | |
| Mass | 1.14±0.02[4] M☉ |
| Radius | 1.28±0.03[4] R☉ |
| Luminosity | 1.81±0.01[4] L☉ |
| Surface gravity (log g) | 4.27±0.02[4] cgs |
| Temperature | 5,917±52[4] K |
| Metallicity [Fe/H] | 0.206±0.030[5] dex |
| Rotational velocity (v sin i) | 2.39±0.050[5] km/s |
| Age | 4.8±0.8[4] Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
This is a G-type main-sequence star with a stellar classification of G2V.[3] It is a metal-rich star with an age of around 4.8 billion years. The star has 14% more mass than the Sun and 128% of the Sun's radius. It is radiating 1.8 times the luminosity of the Sun from its photosphere at an effective temperature of 5,917 K.[4] The star is spinning slowly with a projected rotational velocity of 2.4 km/s.[5]
Planetary system
editA long period planet was discovered in 2006 based on observations made at the W. M. Keck Observatory in Hawaii. However because the observations covered less than one complete orbit there were only weak constraints on the period and mass.[5] The first reliable orbit for HD 24040b was obtained by astronomers at Haute-Provence Observatory in 2012 who combined the keck measurements with ones from the SOPHIE and ELODIE spectrographs.[7] The most recent orbit published in 2015 added additional keck measurements and refined the orbital parameters.[8]
A linear trend in the radial velocities indicating a possible additional companion was detected at Haute-Provence Observatory and was also detected at keck but at a much smaller amplitude.[7][8] The linear trend was confirmed in 2021, together with the discovery of another planet, HD 24040 c.[9]
Planet c is in the habitable zone, with an ecc of <0.2, and may have a habitable moon.
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| c | ≥0.201±0.027 MJ | 1.3±0.021 | 515.4+2.2 −2.5 |
0.11+0.120 −0.079 |
— | — |
| b | >4.10±0.12 MJ | 4.637±0.067 | 3490±25 | 0.047±0.020 | — | — |
See also
editReferences
edit- ^ 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.
- ^ 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.
- ^ a b Sharma, Kaushal; et al. (January 2020). "Application of convolutional neural networks for stellar spectral classification". Monthly Notices of the Royal Astronomical Society. 491 (2): 2280–2300. arXiv:1909.05459. Bibcode:2020MNRAS.491.2280S. doi:10.1093/mnras/stz3100.
- ^ a b c d e f g Bonfanti, A.; et al. (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.
- ^ a b c d Wright, J. T.; et al. (2007). "Four New Exoplanets and Hints of Additional Substellar Companions to Exoplanet Host Stars". The Astrophysical Journal. 657 (1): 533–545. arXiv:astro-ph/0611658. Bibcode:2007ApJ...657..533W. doi:10.1086/510553. S2CID 35682784.
- ^ "HD 24040". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2023-12-12.
- ^ a b Boisse, Isabelle; et al. (2012), "The SOPHIE search for northern extrasolar planets V. Follow-up of ELODIE candidates: Jupiter-analogs around Sun-like stars", Astronomy and Astrophysics, 545: A55, arXiv:1205.5835, Bibcode:2012A&A...545A..55B, doi:10.1051/0004-6361/201118419, S2CID 119109836
- ^ a b c Feng, Y. Katherina; et al. (2015). "The California Planet Survey IV: A Planet Orbiting the Giant Star HD 145934 and Updates to Seven Systems with Long-period Planets". The Astrophysical Journal. 800 (1). 22. arXiv:1501.00633. Bibcode:2015ApJ...800...22F. doi:10.1088/0004-637X/800/1/22. S2CID 56390823.
- ^ a b Rosenthal, Lee J.; et al. (2021), "The California Legacy Survey. I. A Catalog of 178 Planets from Precision Radial Velocity Monitoring of 719 Nearby Stars over Three Decades", The Astrophysical Journal Supplement Series, 255 (1): 8, arXiv:2105.11583, Bibcode:2021ApJS..255....8R, doi:10.3847/1538-4365/abe23c, S2CID 235186973
External links
edit- "Notes for star HD 24040". Extrasolar Planets Encyclopaedia. Archived from the original on February 24, 2007.