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Star in the constellation Leo Minor
20 Leonis Minoris is a
binary star system in the northern
constellation of
Leo Minor . It is faintly visible to the naked eye, having an
apparent visual magnitude of +5.4.
[2] Based upon an annual
parallax shift of 66.46
mas , it is located 49
light years from the Sun. The star has a relatively high
proper motion
[3] and is moving away from the Sun with a
radial velocity of +56 km/s.
[6] The system made its closest approach about 150,000 years ago when it came within 32.2 ly (9.86 pc).
[13]
The primary member of this system is a
G-type main-sequence star with a
stellar classification of G3 Va
Hδ 1 .
[3] It has 12% more mass and a 25% larger radius than the Sun. The star is about seven
[11] billion years old and is spinning with a rotation period of 10.6 days.
[2] The small companion is an
active
red dwarf star that has a relatively high
metallicity .
[14] The two stars are currently separated by 14.5
arc seconds , corresponding to a
projected separation of 2016
AU .
[8]
In 2020, a candidate
exoplanet was detected orbiting 20 Leonis Minoris (HD 86728). With a
minimum mass of 0.032
M J (10.2
M E ) and an orbital period of 31 days, this would most likely be a
hot Neptune .
[15]
References
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a
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d
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^
a
b Gontcharov, G. A. (2006). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system". Astronomy Letters . 32 (11): 759–771.
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a
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^ Kovtyukh; Soubiran, C.; Belik, S. I.; Gorlova, N. I. (2003), "High precision effective temperatures for 181 F-K dwarfs from line-depth ratios",
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^
a
b Hirsch, Lea A.; et al. (2021), "Understanding the Impacts of Stellar Companions on Planet Formation and Evolution: A Survey of Stellar and Planetary Companions within 25 pc",
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arXiv :
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Bibcode :
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doi :
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S2CID
229297873 .
External links
See also