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]

HD 99109
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
Distance160 ± 10 ly
(50 ± 3 pc)
Absolute magnitude (MV)+5.19
Details
Mass0.93 M☉
Luminosity0.724 L☉
Temperature5272 K
Metallicity2.07 × Sun
Age>12.2 Gyr
Other designations
Shama, BD–00°2437, HIP 55664, SAO 138182
Database references
SIMBADdata

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]

The HD 99109 planetary system[2]
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 — —
gollark: The switch actually disables the speed of light.
gollark: Unrelatedly, OBSERVE gaming.
gollark: Works quite well in some people who are resistant to other treatment.
gollark: It is actually used (legally) as an antidepressant now.
gollark: But you could simply become non-lazy and do that.

References
  1. 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.Vizier catalog entry
  2. 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.
  3. "Approved names". NameExoworlds. Retrieved 2020-01-02.
  4. "International Astronomical Union | IAU". www.iau.org. Retrieved 2020-01-02.
  5. 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


This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.