Astronomy:HD 191939

From HandWiki
Short description: Star in the constellation Draco
HD 191939
HD191939 location.png
Location of HD 191939 in the night sky. The star is marked within the red diamond.
Observation data
Epoch J2000.0   Equinox (celestial coordinates)
Constellation Draco
Right ascension  20h 08m 05.75515s[1]
Declination +66° 51′ 02.0766″[1]
Apparent magnitude (V) 8.971[2]
Characteristics
HD 191939
Evolutionary stage main sequence
Spectral type G9V[3]
Astrometry
Radial velocity (Rv)−9.23±0.16[1] km/s
Proper motion (μ) RA: 150.194±0.015[1] mas/yr
Dec.: −63.988±0.017[1] mas/yr
Parallax (π)18.6967 ± 0.0133[1] mas
Distance174.4 ± 0.1 ly
(53.49 ± 0.04 pc)
Absolute magnitude (MV)5.32
Details[3]
HD 191939
Mass0.81±0.04 M☉
Radius0.94±0.02 R☉
Luminosity (bolometric)0.65±0.02 L☉
Surface gravity (log g)4.3±0.1 cgs
Temperature5348±100 K
Metallicity [Fe/H]−0.15±0.06 dex
Rotational velocity (v sin i)0.6±0.5[4] km/s
Age7±3[4] Gyr
Other designations
Gaia DR2 2248126315275354496, HD 191939, HIP 99175, TYC 4244-964-1, 2MASS J20080574+6651019[5]
Database references
SIMBADdata
Exoplanet Archivedata
Extrasolar Planets
Encyclopaedia		data

HD 191939 is a single yellow (G-type) main-sequence star, located approximately 174 light-years away in the constellation of Draco, taking its primary name from its Henry Draper Catalogue designation.

Characteristics

HD 191939 is a Sun-like G-type main-sequence star, likely older than the Sun and relatively depleted in metals.

Planetary system

In 2020, an analysis carried out by a team of astronomers led by astronomer Mariona Badenas-Agusti of the TESS project confirmed the existence of three gaseous planets, all smaller than Neptune, in orbit around HD 191939.[4] Another non-transiting gas giant planet designated HD 191939 e was detected in 2021, along with a substellar object on a highly uncertain, 9 to 46 year orbit.[3] In 2022, a sixth planet, with a mass comparable to Uranus, was discovered in the system's habitable zone.[6] The 2021 study also suggested the possible presence of an additional non-transiting planet with a period of 17.7 days,[3] but the 2022 study did not support this.[6]

The HD 191939 planetary system[6]
Companion
(in order from star) 		Mass Semimajor axis
(AU) 		Orbital period
(days) 		Eccentricity Inclination Radius
b 10.00±0.70 M⊕ 0.0804+0.0025
−0.0023 		8.8803256 0.031+0.010
−0.011 		88.10+0.14
−0.10° 		3.410±0.075 R⊕
c 8.0±1.0 M⊕ 0.1752+0.0055
−0.0050 		28.579743 0.034+0.034
−0.013 		89.10+0.06
−0.08° 		3.195±0.075 R⊕
d 2.80±0.60 M⊕ 0.2132+0.0065
−0.0061 		38.353037 0.031+0.018
−0.012 		89.49+0.05
−0.08° 		2.995±0.070 R⊕
e ≥112.2±4.0 M⊕ 0.407±0.012 101.12±0.13 0.031+0.008
−0.016 		88.7±0.7[3]° —
g ≥13.5±2.0 M⊕ 0.812±0.028 284+10
−8 		0.030+0.025
−0.011 		— —
f >2.08 MJ >3.2 >2200 — — —

See also

References

  1. ↑ 1.0 1.1 1.2 1.3 1.4 Vallenari, A. et al. (2022). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy & Astrophysics. doi:10.1051/0004-6361/202243940  Gaia DR3 record for this source at VizieR.
  2. ↑ "HD 191939 - Star - SKY-MAP". http://news.sky-map.org/starview?object_type=1&object_id=1114234&object_name=HIP+99175&locale=KX. 
  3. ↑ 3.0 3.1 3.2 3.3 3.4 Lubin, Jack et al. (2022). "TESS-Keck Survey. IX. Masses of Three Sub-Neptunes Orbiting HD 191939 and the Discovery of a Warm Jovian plus a Distant Substellar Companion". The Astronomical Journal 163 (2): 101. doi:10.3847/1538-3881/ac3d38. Bibcode: 2022AJ....163..101L. 
  4. ↑ 4.0 4.1 4.2 Badenas-Agusti, Mariona; Günther, Maximilian N.; Daylan, Tansu; Mikal-Evans, Thomas; Vanderburg, Andrew; Huang, Chelsea X.; Matthews, Elisabeth; Rackham, Benjamin V. et al. (2020). "HD 191939: Three Sub-Neptunes Transiting a Sun-like Star Only 54 pc Away". The Astronomical Journal 160 (3): 113. doi:10.3847/1538-3881/aba0b5. Bibcode: 2020AJ....160..113B. 
  5. ↑ "HD 191939". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=HD+191939. 
  6. ↑ 6.0 6.1 6.2 Orell-Miquel, J.; Nowak, G.; Murgas, F.; Palle, E.; Morello, G.; Luque, R.; Badenas-Agusti, M.; Ribas, I. et al. (2023). "HD 191939 revisited: New and refined planet mass determinations, and a new planet in the habitable zone". Astronomy & Astrophysics 669: A40. doi:10.1051/0004-6361/202244120. Bibcode: 2023A&A...669A..40O. 

Coordinates: Sky map 20h 08m 5.75s, ++66° 51′ 2.1″

Template:2021 in space



Retrieved from "https://handwiki.org/wiki/index.php?title=Astronomy:HD_191939&oldid=3353425"