HD 99109
HD 99109 is an orange dwarf star approximately 160 light-years away[1] in the constellation of Leo. The star is thought to have about 93% as massive, probably smaller, and 72.4% the luminosity of the Sun. It is over twice the abundance of iron relative to hydrogen than the Sun. The star is one and half degree away from the celestial equator to the south. As of 2006, one extrasolar planet has been confirmed to be orbiting the star.[2]
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Leo |
| Right ascension | 11h 24m 17.359s[1] |
| Declination | –01° 31′ 44.66″[1] |
| Apparent magnitude (V) | +9.10 |
| Characteristics | |
| Spectral type | K0V |
| B−V color index | +0.87 |
| Variable type | Suspected |
| Astrometry | |
| Proper motion (μ) | RA: –178.07 ± 1.18[1] mas/yr Dec.: –159.26 ± 1.11[1] mas/yr |
| Parallax (π) | 20.03 ± 1.38[1] mas |
| Distance | 160 ± 10 ly (50 ± 3 pc) |
| Absolute magnitude (MV) | +5.19 |
| Details | |
| Mass | 0.93 M☉ |
| Luminosity | 0.724 L☉ |
| Temperature | 5272 K |
| Metallicity | 2.07 × Sun |
| Age | >12.2 Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
The star HD 99109 is named Shama. The name was selected in the NameExoWorlds campaign by Pakistan, during the 100th anniversary of the IAU. Shama is an Urdu literary term meaning a small lamp or flame.[3][4]
Planetary system
The planet HD 99109 b has an orbit comparable in eccentricity to the planet Mars in the Solar System but has a mass at least half that of Jupiter. Stability analysis reveals that Earth-size planets could have stable orbits in the planet's Trojan points, located 60 degrees ahead and behind the planet's position in its orbit.[5]
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b | >0.502 ± 0.070 MJ | 1.105 ± 0.065 | 439.3 ± 5.6 | 0.09 ± 0.16 | — | — |
References
- van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics. 474 (2): 653–664. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357. S2CID 18759600.Vizier catalog entry
- Butler, R. P.; et al. (2006). "Catalog of Nearby Exoplanets". The Astrophysical Journal. 646 (1): 505–522. arXiv:astro-ph/0607493. Bibcode:2006ApJ...646..505B. doi:10.1086/504701. S2CID 119067572.
- "Approved names". NameExoworlds. Retrieved 2020-01-02.
- "International Astronomical Union | IAU". www.iau.org. Retrieved 2020-01-02.
- R. Schwarz; R. Dvorak; Á. Süli; B. Érdi (November 2007). "Survey of the stability region of hypothetical habitable Trojan planets". Astronomy & Astrophysics. 474 (3): 1023–1029. Bibcode:2007A&A...474.1023S. doi:10.1051/0004-6361:20077994.: HD 93083, HD 17051, HD 28185, HD 27442, HD 188015, HD 99109, HD 221287
External links
- "Notes for star HD 99109". The Extrasolar Planets Encyclopedia. Retrieved 2008-07-16.