Astronomy:HD 140913
| Observation data Equinox J2000.0]] (ICRS) | |
|---|---|
| Constellation | Corona Borealis |
| Right ascension | 15h 45m 07.44910s[1] |
| Declination | +28° 28′ 11.7388″[1] |
| Apparent magnitude (V) | 8.07[2] |
| Characteristics | |
| Spectral type | G0V[3] |
| B−V color index | 0.612±0.007[4] |
| Astrometry | |
| Radial velocity (Rv) | −20.38±0.21[1] km/s |
| Proper motion (μ) | RA: −87.880[1] mas/yr Dec.: 37.978[1] mas/yr |
| Parallax (π) | 20.4949 ± 0.0367[1] mas |
| Distance | 159.1 ± 0.3 ly (48.79 ± 0.09 pc) |
| Absolute magnitude (MV) | 4.81[2] |
| Orbit[5] | |
| Period (P) | 147.912+0.022 −0.023 d |
| Semi-major axis (a) | 0.561+0.015 −0.016 astronomical unit|AU |
| Eccentricity (e) | 0.5223±0.0081 |
| Inclination (i) | 30.3±1.3° |
| Longitude of the node (Ω) | 311.0±1.6° |
| Periastron epoch (T) | 2,457,387.33±0.90 JD |
| Argument of periastron (ω) (secondary) | 23.7+2.1 −1.8° |
| Semi-amplitude (K1) (primary) | 2.023±0.073 km/s |
| Details[5] | |
| Mass | 0.987±0.087 M☉ |
| Radius | 1.034±0.021 R☉ |
| Luminosity | 1.32+0.15 −0.11 L☉ |
| Surface gravity (log g) | 4.403+0.042 −0.050 cgs |
| Temperature | 6,090+180 −140 K |
| Metallicity [Fe/H] | −0.26+0.21 −0.23 dex |
| Rotational velocity (v sin i) | 9.7[2] km/s |
| Age | 7.13[2] Gyr |
| HD 140913 b | |
| Mass | 93.3+1.7 −1.6 MJup |
| Other designations | |
| Database references | |
| SIMBAD | data |
HD 140913 is a Sun-like star located in the northern constellation of Corona Borealis (The Northern Crown). It is too faint to be visible to the naked eye with an apparent visual magnitude of 8.07.[2] The star is located at a distance of 159 light-years from the Sun based on parallax. Prior to the discovery of a companion, this served as an IAU radial velocity standard,[7] and it is receding from the Sun at a rate of +37 km/s.[8] The space velocity components of this star are (U, V, W) = (-21.77, -14.42, 1.67).[3]
Physical characteristics
HD 140913 is a solar-type star[9] with a spectral type of G0V.[3] It is estimated to be seven billion years old and is spinning with a projected rotational velocity of 9.7 km/s.[2] The star is about the same size as the Sun and 92% of it's mass.[2] It is radiating 1.3 times the Sun's luminosity from its photosphere at an effective temperature of 6,090 K.[5]
Companion
The detection of an orbiting companion, designated HD 140913 B, was announced in 1994.[7][9] The minimum mass of this object is 43.2 times the mass of Jupiter, making it a brown dwarf candidate. Alternatively, it may be an under-mass helium white dwarf that has lost its envelope during a mass transfer.[10] It orbits the host star about every 148 days with an eccentricity (ovalness) of ~0.57 and a semimajor axis of at least 0.55 astronomical unit|AU.[11]
In 2023, the true mass of this companion was determined using Gaia astrometry. Two different studies find masses ranging from about 75 to about 93 Jupiter masses, placing this object near the boundary between brown dwarfs and low-mass stars.[12][5]
References
- ↑ 1.0 1.1 1.2 1.3 1.4 Vallenari, A. et al. (2022). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy & Astrophysics. doi:10.1051/0004-6361/202243940 Gaia DR3 record for this source at VizieR.
- ↑ 2.0 2.1 2.2 2.3 2.4 2.5 2.6 Luck, R. Earle (January 2017). "Abundances in the Local Region II: F, G, and K Dwarfs and Subgiants". The Astronomical Journal 153 (1): 19. doi:10.3847/1538-3881/153/1/21. 21. Bibcode: 2017AJ....153...21L.
- ↑ 3.0 3.1 3.2 Montes, D. et al. (November 2001). "Late-type members of young stellar kinematic groups - I. Single stars". Monthly Notices of the Royal Astronomical Society 328 (1): 45–63. doi:10.1046/j.1365-8711.2001.04781.x. Bibcode: 2001MNRAS.328...45M. http://eprints.ucm.es/30941/1/castrorubio18libre.pdf. Retrieved 2018-11-04.
- ↑ Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters 38 (5): 331. doi:10.1134/S1063773712050015. Bibcode: 2012AstL...38..331A.
- ↑ 5.0 5.1 5.2 5.3 Unger, N. et al. (December 2023). "Exploring the brown dwarf desert with precision radial velocities and Gaia DR3 astrometric orbits". Astronomy & Astrophysics 680: A16. doi:10.1051/0004-6361/202347578. Bibcode: 2023A&A...680A..16U.
- ↑ "HD 140913". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=HD+140913.
- ↑ 7.0 7.1 Stefanik, R. P.; Latham, D. W.; Scarfe, C. D.; Mazeh, T.; Davis, R. J.; Torres, G. (May 1994). "The Unseen Companion of HD 140913: Another Brown Dwarf Candidate". American Astronomical Society, 184th AAS Meeting, id.43.07. 26. 931. Bibcode: 1994AAS...184.4307S.
- ↑ Evans, D. S. (1967). "The revision of the general catalogue of radial velocities". in Batten, Alan Henry; Heard, John Frederick. University of Toronto: Academic Press. Bibcode: 1967IAUS...30...57E.
- ↑ 9.0 9.1 Mazeh, Tsevi et al. (1996). "Spectroscopic Orbits for Three Binaries with Low-Mass Companions and the Distribution of Secondary Masses near the Substellar Limit". The Astrophysical Journal 466: 415–426. doi:10.1086/177521. Bibcode: 1996ApJ...466..415M.
- ↑ Nelemans, G.; Tauris, T. M. (July 1998). "Formation of undermassive single white dwarfs and the influence of planets on late stellar evolution". Astronomy and Astrophysics 335: L85–L88. Bibcode: 1998A&A...335L..85N.
- ↑ Nidever, David L. et al. (August 2002). "Radial Velocities for 889 Late-Type Stars". The Astrophysical Journal Supplement Series 141 (2): 503–522. doi:10.1086/340570. Bibcode: 2002ApJS..141..503N.
- ↑ Stevenson, Adam T. et al. (December 2023). "Combing the brown dwarf desert with Gaia DR3". Monthly Notices of the Royal Astronomical Society 526 (4): 5155–5171. doi:10.1093/mnras/stad3041. Bibcode: 2023MNRAS.526.5155S.
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