Astronomy:HD 102117
| Observation data Equinox J2000.0]] (ICRS) | |
|---|---|
| Constellation | Centaurus |
| Right ascension | 11h 44m 50.46084s[1] |
| Declination | –58° 42′ 13.3564″[1] |
| Apparent magnitude (V) | 7.47[2] |
| Characteristics | |
| Spectral type | G6V[3] |
| B−V color index | 0.721±0.009[2] |
| Variable type | Constant[4] |
| Astrometry | |
| Radial velocity (Rv) | +49.64±0.13[1] km/s |
| Proper motion (μ) | RA: –63.555[1] mas/yr Dec.: –70.439[1] mas/yr |
| Parallax (π) | 25.2369 ± 0.0409[1] mas |
| Distance | 129.2 ± 0.2 ly (39.62 ± 0.06 pc) |
| Absolute magnitude (MV) | 4.48[2] |
| Details | |
| Mass | 1.37±0.130 M☉[5] 1.03±0.05[6] M☉ |
| Radius | 1.27[7] R☉ |
| Luminosity | 1.54[7] L☉ |
| Surface gravity (log g) | 4.37±0.06[7] cgs |
| Temperature | 5,695±44[5] K |
| Metallicity [Fe/H] | 0.30±0.03[6] dex |
| Rotational velocity (v sin i) | 0.88±0.5[7] km/s |
| Age | 5.3±3.4[5] Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
| Extrasolar Planets Encyclopaedia | data |
HD 102117 or Uklun /ˈʌklən/ is a star in the southern constellation of Centaurus. With an apparent visual magnitude of 7.47,[2] it is too dim to be seen without binoculars or a small telescope. It is located at a distance of approximately 129 light years from the Sun based on parallax. HD 102117 is drifting further away with a radial velocity of +50 km/s,[1] having come to within 43.9 light-years some 692,000 years ago.[2] It has one known planet.[6]
The stellar classification of HD 102117 is G6V,[8] which matches the spectrum of an ordinary G-type main-sequence star. It is roughly five[5] billion years old and is spinning with a projected rotational velocity of 0.9 km/s.[7] The star shows only a low level of chromospheric activity[6] and is photometrically stable,[4] meaning it doesn't vary significantly in brightness. It appears metal-enriched,[4] showing a higher abundance of heavy elements compared to the Sun.
Planetary system
In 2004, the Anglo-Australian Planet Search announced a planet orbiting the star.[4] A short time later the HARPS team also announced the presence of a planet around this star. Both groups detected this planet with the radial velocity method.[6]
HD 102117, and its planet HD 102117b, were chosen as part of the 2019 NameExoWorlds campaign organised by the International Astronomical Union, which assigned each country a star and planet to be named. HD 102117 was assigned to Pitcairn Islands. The winning proposal named the star Uklun, from the word aklan 'we/us' in the Pitcairn language, and the planet Leklsullun /lɛkəlsʌlən/, from the phrase lekl salan 'child/children' (lit. 'little person').[9]
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b / Leklsullun | 0.172 ± 0.020 MJ | 0.1532 ± 0.0088 | 20.8133 ± 0.0064 | 0.121 ±0.082 | — | — |
See also
- List of extrasolar planets
- HARPS spectrograph
- Anglo-Australian Planet Search
References
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 1.6 Brown, A. G. A. (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics 616: A1. doi:10.1051/0004-6361/201833051. Bibcode: 2018A&A...616A...1G. Gaia DR2 record for this source at VizieR.
- ↑ 2.0 2.1 2.2 2.3 2.4 Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters 38 (5): 331, doi:10.1134/S1063773712050015, Bibcode: 2012AstL...38..331A
- ↑ 3.0 3.1 "HD 102117". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=HD+102117.
- ↑ 4.0 4.1 4.2 4.3 Tinney, C. G. et al. (2005). "Three Low-Mass Planets from the Anglo-Australian Planet Search". The Astrophysical Journal 623 (2): 1171–1179. doi:10.1086/428661. Bibcode: 2005ApJ...623.1171T.
- ↑ 5.0 5.1 5.2 5.3 Valenti, Jeff A.; Fischer, Debra A. (July 2005), "Spectroscopic Properties of Cool Stars (SPOCS). I. 1040 F, G, and K Dwarfs from Keck, Lick, and AAT Planet Search Programs", The Astrophysical Journal Supplement Series 159 (1): 141–166, doi:10.1086/430500, Bibcode: 2005ApJS..159..141V
- ↑ 6.0 6.1 6.2 6.3 6.4 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.
- ↑ 7.0 7.1 7.2 7.3 7.4 "SPOCS I", Exoplanets (Yale University), http://exoplanets.astro.yale.edu/science/analysis/spocs.php, retrieved 2012-01-31
- ↑ Houk, Nancy (1979). Michigan catalogue of two-dimensional spectral types for the HD stars. 1. Ann Arbor, Michigan: Department of Astronomy, University of Michigan. Bibcode: 1978mcts.book.....H.
- ↑ "Pitcairn Islands" (in en). http://www.nameexoworlds.iau.org/pitcairn-islands.
- ↑ Butler, R. P. et al. (2006). "Catalog of Nearby Exoplanets". The Astrophysical Journal 646 (1): 505–522. doi:10.1086/504701. Bibcode: 2006ApJ...646..505B.
External links
Coordinates: 
11h 44m 50.4616s, −58° 42′ 13.354″
 |  |
