Astronomy:HD 93083
| Observation data Equinox J2000.0]] (ICRS) | |
|---|---|
| Constellation | Antlia[1] |
| Right ascension | 10h 44m 20.91501s[2] |
| Declination | −33° 34′ 37.2880″[2] |
| Apparent magnitude (V) | 8.30[1] |
| Characteristics | |
| Evolutionary stage | Main sequence[3] |
| Spectral type | K2IV-V[4] or K3V[5][6] |
| B−V color index | 0.945±0.001[1] |
| Astrometry | |
| Radial velocity (Rv) | +43.44±0.12[2] km/s |
| Proper motion (μ) | RA: −92.635[2] mas/yr Dec.: −152.119[2] mas/yr |
| Parallax (π) | 35.1056 ± 0.0212[2] mas |
| Distance | 92.91 ± 0.06 ly (28.49 ± 0.02 pc) |
| Absolute magnitude (MV) | 6.08[1] |
| Details[7] | |
| Mass | 0.836+0.023 −0.025 M☉ |
| Radius | 0.837+0.026 −0.018 R☉ |
| Luminosity | 0.407+0.038 −0.031 L☉ |
| Surface gravity (log g) | 4.23±0.07 cgs |
| Temperature | 5,034+86 −77 K |
| Metallicity [Fe/H] | 0.13±0.07 dex |
| Rotation | 32.3+1.2 −1.3 d |
| Rotational velocity (v sin i) | 2.219±0.531[8] km/s |
| Age | 10.71+2.24 −1.25 Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
| Exoplanet Archive | data |
| ARICNS | data |
HD 93083 (or GJ 1137) is an orange-hued star in the southern constellation of Antlia. It has the proper name Macondo, after the mythical village of the novel One Hundred Years of Solitude (Cien años de soledad). The name was selected by Colombia during the IAU's NameExoWorlds campaign.[10][11] The star has an apparent visual magnitude of 8.30,[1] which is too faint to be visible to the naked eye. It is located at a distance of 93 light-years from the Sun based on parallax. HD 93083 is drifting further away with a radial velocity of +43.65 km/s, having come to within 43 light-years some 484,000 years ago.[1]
This is a K-type main-sequence star that has been assigned a stellar classification of K2IV-V[4] or K3V,[5][6] depending on the study. It is smaller and less massive than the Sun, with a higher metallicity, or abundance of elements heavier than helium.[8] The star is roughly six billion years old with a low projected rotational velocity of 2.2 km/s, and has an expected main sequence lifetime of 20.4 billion years.[3] It is a source of X-ray emission with a luminosity of 7.9×1026 erg s−1.[5] The star is radiating around 41%[6] of the luminosity of the Sun from its photosphere at an effective temperature of 5,030 K.[8]
Planetary system
In 2005, the discovery of a Saturn-mass exoplanet orbiting the star was announced. This was a discovery using the radial velocity method with the HARPS spectrograph.[6] The planet was given the name Melquíades by the IAU in 2019 after a character in the book One Hundred Years of Solitude.[10] The orbit of this body is in or near the habitable zone of the host star; according to a 2007 study, it is entirely within the habitable zone,[3] but more recent models place it near the inner edge.[7] It is theoretically possible that a large moon orbiting the planet, or a hypothetical terrestrial exoplanet at a trojan point, could be habitable.[3]
A second planet was found in 2026, also with HARPS radial velocity observations. It is a super-Earth at least 5 times Earth's mass, orbiting with a short period of 9.6 days. Another long-period radial velocity signal is due to the star's magnetic activity cycle rather than a planet.[7]
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| c | ≥5.12+0.70 −0.69 M⊕ |
0.0835±0.0008 | 9.6412+0.0012 −0.0011 |
0 | — | — |
| b / Melquíades | ≥0.451±0.012 MJ | 0.508±0.005 | 144.720±0.029 | 0.118+0.016 −0.015 |
— | — |
See also
- List of extrasolar planets
- HARPS spectrograph
References
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters 38 (5): 331. doi:10.1134/S1063773712050015. Bibcode: 2012AstL...38..331A XHIP record for this object at VizieR.
- ↑ 2.0 2.1 2.2 2.3 2.4 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.
- ↑ 3.0 3.1 3.2 3.3 Schwarz, R. et al. (November 2007). "Survey of the stability region of hypothetical habitable Trojan planets". Astronomy and Astrophysics 474 (3): 1023–1029. doi:10.1051/0004-6361:20077994. Bibcode: 2007A&A...474.1023S.
- ↑ 4.0 4.1 Gray, R. O. et al. (October 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): 2048–2059, doi:10.1086/378365, Bibcode: 2003AJ....126.2048G
- ↑ 5.0 5.1 5.2 Sanz-Forcada, J. et al. (September 2010). "A scenario of planet erosion by coronal radiation (Corrigendum)". Astronomy and Astrophysics 520: 2. doi:10.1051/0004-6361/200913670e. C1. Bibcode: 2010A&A...520C...1S.
- ↑ 6.0 6.1 6.2 6.3 Lovis, C. et al. (2005). "The HARPS search for southern extra-solar planets III. Three Saturn-mass planets around HD 93083, HD 101930 and HD 102117". Astronomy and Astrophysics 437 (3): 1121–1126. doi:10.1051/0004-6361:20052864. Bibcode: 2005A&A...437.1121L. http://www.aanda.org/articles/aa/full/2005/27/aa2864-05/aa2864-05.html.
- ↑ 7.0 7.1 7.2 7.3 Stoeva, Denitza et al. (March 2026). "Long-period magnetic activity in the K dwarf GJ 1137 and a new super-Earth on a 9-day orbit". Astronomy & Astrophysics. doi:10.1051/0004-6361/202557806.
- ↑ 8.0 8.1 8.2 Soto, M. G.; Jenkins, J. S. (2018). "Spectroscopic Parameters and atmosphEric ChemIstriEs of Stars (SPECIES). I. Code description and dwarf stars catalogue". Astronomy and Astrophysics 615: A76. doi:10.1051/0004-6361/201731533. Bibcode: 2018A&A...615A..76S.
- ↑ "HD 93083". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=HD+93083.
- ↑ 10.0 10.1 "Approved names" (in en). IAU. http://www.nameexoworlds.iau.org/final-results.
- ↑ "International Astronomical Union | IAU". https://www.iau.org/news/pressreleases/detail/iau1912/.
Further reading
- Saffe, C. et al. (2005). "On the Ages of Exoplanet Host Stars". Astronomy and Astrophysics 443 (2): 609–626. doi:10.1051/0004-6361:20053452. Bibcode: 2005A&A...443..609S.
Coordinates: 
10h 44m 20.9149s, −35° 34′ 37.279″
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