Lambda Bootis
Star Lambda Bootis (λ Bootis) |
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AladinLite | |||||||||||||||||||||
Observation dates equinox : J2000.0 , epoch : J2000.0 |
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Constellation | Bear keeper | ||||||||||||||||||||
Right ascension | 14 h 16 m 23.02 s | ||||||||||||||||||||
declination | + 46 ° 05 ′ 17.9 ″ | ||||||||||||||||||||
Apparent brightness | 4.18 likes | ||||||||||||||||||||
Typing | |||||||||||||||||||||
B − V color index | +0.08 | ||||||||||||||||||||
U − B color index | +0.05 | ||||||||||||||||||||
R − I index | +0.03 | ||||||||||||||||||||
Spectral class | A0sh | ||||||||||||||||||||
Astrometry | |||||||||||||||||||||
Radial velocity | (−7.9 ± 1.6) km / s | ||||||||||||||||||||
parallax | (32.94 ± 0.16) mas | ||||||||||||||||||||
distance | (99.0 ± 0.5) ly (30.4 ± 0.1) pc |
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Visual absolute brightness M vis | +1.8 likes | ||||||||||||||||||||
Proper movement | |||||||||||||||||||||
Rec. Share: | (−187.33 ± 0.14) mas / a | ||||||||||||||||||||
Dec. portion: | (+159.05 ± 0.11) mas / a | ||||||||||||||||||||
Physical Properties | |||||||||||||||||||||
Other names and catalog entries |
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Lambda Bootis (λ Boo, λ Bootis) is a star in the Bear Keeper constellation .
Lambda Bootis is a star in the main sequence of the spectral class A with an apparent magnitude of +4.18 mag. It is about 97.1 light years from Earth . Lambda Bootis is the prototype of a group of rare stars that are named after him as Lambda Bootis stars . The members of this group are dwarf stars and their spectra show that they are very metal-poor. Their diameters were measured directly and are roughly 1.7 times that of the sun .
The star was named Xuange by the IAU on June 30, 2017 .
Web links
Individual evidence
- ↑ a b c Hipparcos catalog (ESA 1997)
- ↑ a b c Bright Star Catalog
- ↑ Pulkovo radial velocities for 35493 HIP stars
- ^ A b Hipparcos, the New Reduction (van Leeuwen, 2007)
- ↑ Ciardi et al. , Gerard T. Van Belle, Andrew F. Boden, T. Ten Brummelaar, HA McAlister, WG Bagnuolo, Jr., PJ Goldfinger, J. Sturmann et al. a .: The Angular Diameter of λ Bootis . In: The Astrophysical Journal . 659, No. 2, 2007, pp. 1623-1628. doi : 10.1086 / 512077 .