Gliese 849

Gliese 849 is a M3.5V red dwarf star approximately 29 light years away in the constellation of Aquarius. It has the first planet discovered orbiting a red dwarf with a semi-major axis greater than 0.21 AU.[4]

Gliese 849

Observation data Epoch J2000.0      Equinox J2000.0
Constellation	Aquarius
Right ascension	22^h 9^m 40.3444^s[1]
Declination	–4° 38′ 26.6513″[1]
Apparent magnitude (V)	10.42
Characteristics
Spectral type	M3.5V
U−B color index	1.13
B−V color index	1.51
V−R color index	1.11
R−I color index	1.41
Astrometry
Radial velocity (Rv)	−12 ± 5 km/s
Proper motion (μ)	RA: 1132.534±0.081[1] mas/yr Dec.: −22.125±0.083[1] mas/yr
Parallax (π)	113.6000 ± 0.0463[1] mas
Distance	28.71 ± 0.01 ly (8.803 ± 0.004 pc)
Absolute magnitude (MV)	10.70
Details
Mass	0.36 M☉
Radius	0.52 ± 0.07 R☉
Luminosity	0.029 L☉
Surface gravity (log g)	4.66 cgs
Temperature	3,601 ± 19[2] K
Metallicity	+0.31 ± 0.17[2]
Rotation	39.2±6.3 d[3]
Other designations
BD-05 5715, GCRV 13921, HIP 109388, LFT 1689, LHS 517, LPM 814, LTT 8889, NLTT 53078
Database references
SIMBAD	data
Exoplanet Archive	data
ARICNS	data
Planet
Gliese 849b	data

Planetary system

In late 2006, a long-period Jupiter-like planet 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.[5] The trend in the radial velocities was confirmed in 2013.[6] An orbit for the second planet was finally determined in 2015.[4]

The Gliese 849 planetary system[4]

Companion (in order from star)	Mass	Semimajor axis (AU)	Orbital period (days)	Eccentricity	Inclination	Radius
b	>0.911±0.036 MJ	2.39±0.082	1924±15	0.038±0.019	—	—
c	>0.944±0.070 MJ	4.82±0.21	5520±390	0.087±0.056	—	—

See also

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

References

1. Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
2. Rojas-Ayala, Bárbara; et al. (April 2012). "Metallicity and Temperature Indicators in M Dwarf K-band Spectra: Testing New and Updated Calibrations with Observations of 133 Solar Neighborhood M Dwarfs" (PDF). The Astrophysical Journal. 748 (2): 93. arXiv:1112.4567. Bibcode:2012ApJ...748...93R. doi:10.1088/0004-637X/748/2/93. See table 3.
3. Suárez Mascareño, A.; et al. (September 2015), "Rotation periods of late-type dwarf stars from time series high-resolution spectroscopy of chromospheric indicators", Monthly Notices of the Royal Astronomical Society, 452 (3): 2745–2756, arXiv:1506.08039, Bibcode:2015MNRAS.452.2745S, doi:10.1093/mnras/stv1441.
4. Feng, Y. Katherina; et al. (2015). "The California Planet Survey IV: A Planet Orbiting the Giant Star HD 145934 and Updates to Seven Systems with Long-period Planets". The Astrophysical Journal. 800 (1). 22. arXiv:1501.00633. Bibcode:2015ApJ...800...22F. doi:10.1088/0004-637X/800/1/22.
5. Butler, R. Paul; et al. (2006). "A Long-Period Jupiter-Mass Planet Orbiting the Nearby M Dwarf GJ 849". Publications of the Astronomical Society of the Pacific. 118 (850): 1685–1689. arXiv:astro-ph/0610179. Bibcode:2006PASP..118.1685B. doi:10.1086/510500.
6. Bonfils, X.; et al. (2013). "The HARPS search for southern extra-solar planets. XXXI. The M-dwarf sample". Astronomy and Astrophysics. 549. A109. arXiv:1111.5019. Bibcode:2013A&A...549A.109B. doi:10.1051/0004-6361/201014704.

External links

• "Gj 849". The Extrasolar Planets Encyclopedia.
• "BD-05 5715 / Gl 849". Solstation.
• "Image: Gliese 849". Aladin Previewer.