• Source: Gliese 849

Gliese 849, or GJ 849, is a small, solitary star in the equatorial constellation of Aquarius. It has a reddish hue and is invisible to the naked eye with an apparent visual magnitude of 10.41. The distance to this star is 28.8 light-years (8.8 parsecs) based on parallax, but it is drifting closer to the Sun with a radial velocity of −15.3 km/s. It has a pair of confirmed gas giant companions.
The stellar classification of GJ 849 is M3.5V, which means this is a small red dwarf star generating energy through hydrogen fusion at its core region. Various studies have found super-solar abundances in the spectra, indicating that the elemental abundances of higher mass elements is significantly higher than in the Sun. The star has about half the mass and size of the Sun, and is spinning slowly with a rotation period of approximately 39 days. The estimated age of the star is more than three billion years. It is radiating a mere 2.9% of the luminosity of the Sun from its photosphere at an effective temperature of 3,490 K.




Planetary system


In late 2006, a long-period Jupiter-like exoplanet was reported to be orbiting the red dwarf in a period just over 5 years in length. There was also a linear trend in the radial velocities which suggested another longer period companion. The trend in the radial velocities was confirmed in 2013. An orbit for the second exoplanet was finally determined in 2015. The first planet discovered, Gliese 849 b, was the first planet discovered orbiting a red dwarf with a semi-major axis greater than 0.21 AU.




See also


List of star systems within 25–30 light-years
Gliese 317
Gliese 649
Gliese 581
List of extrasolar planets




References






External links


"Gj 849". Extrasolar Planets Encyclopaedia. Archived from the original on November 6, 2007.
"BD-05 5715 / Gl 849". Solstation. Archived from the original on 2021-03-30. Retrieved 2007-05-26.
"Image: Gliese 849". Aladin Previewer.

Kata Kunci Pencarian:

• Gliese 849 b
• Gliese 581b
• Gliese 445
• Gliese 581
• Daftar eksoplanet
• Kepler-22b
• Daftar planet luar surya yang ditemukan pada tahun 2000–2009
• Daftar bintang di rasi bintang Hydra
• Daftar bintang di rasi bintang Sagitta
• Gliese 849
• Gliese 849 b
• Aquarius (constellation)
• List of nearest exoplanets
• Gliese 581
• Gliese 581b
• List of smallest known stars
• Gliese 445
• Gliese 649
• Gliese 179 b