Lambda Bootis

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Star
Lambda Bootis (λ Bootis)
AladinLite
Observation
dates equinox :  J2000.0 , epoch : J2000.0
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
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
Bayer name λ bootis
Flamsteed name 19 bootis
Bonn survey BD + 46 ° 1949
Bright Star Catalog HR 5351 [1]
Henry Draper Catalog HD 125162 [2]
Gliese catalog FY 3837 [3]
Hipparcos catalog HIP 69732 [4]
SAO catalog SAO 44965 [5]
2MASS catalog 2MASS J14162308 + 4605177 [6]
Other names Xuange, FK5  527
annotation
  1. ↑ estimated from apparent brightness and distance

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

  1. ↑ a b c Hipparcos catalog (ESA 1997)
  2. ↑ a b c Bright Star Catalog
  3. ↑ Pulkovo radial velocities for 35493 HIP stars
  4. ^ A b Hipparcos, the New Reduction (van Leeuwen, 2007)
  5. ↑ 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 .