U Leporis

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Star
U Leporis
AladinLite
Observation
dates equinoxJ2000.0 , epoch : J2000.0
Constellation Hare
Right ascension 04 h 56 m 17.99 s
declination −21 ° 13 ′ 2 ″
Apparent brightness 10.64 (9.89 to 11.09) mag
Typing
B − V color index (0.12) 
Spectral class A7 to F7
Variable star type RRAB 
Astrometry
Radial velocity (−120) km / s
parallax 0.93 ± 0.03  mas
distance (3,500)  ly
(1,100)  pc
Proper movement 
Rec. Share: (40.79)  mas / a
Dec. portion: (−59.77)  mas / a
Physical Properties
Other names
and catalog entries
Bonn survey BD −21 ° 1019
Henry Draper Catalog HD 31599 [1]
Hipparcos catalog HIP 22952 [2]
Tycho catalog TYC 5912-332-1 [3]
2MASS catalog 2MASS J04561797-2113019 [4]

U Leporis is a giant star about 3500  light years away in the constellation Rabbit . It is an RR Lyrae star and thus belongs to the pulsation variable stars .

As early as 1923, Ejnar Hertzsprung mentioned the variability of U Lep in a contribution .

properties

The star has already passed the red giant phase and is in the helium-burning stage in the core. After the star moved along the horizontal branch in the HR diagram , it landed in the instability strip . Therefore the star pulsates with a period of about 0.58 days (14 hours) between a magnitude of 9.89 to 11.09. The star is a very old star with low metallicity and belongs to the Population II stars

Web links

Individual evidence

  1. a b c d e U Lep. In: SIMBAD . Center de Données astronomiques de Strasbourg , accessed September 9, 2018 .
  2. a b c d U Lep. In: VSX. AAVSO, accessed September 9, 2018 .
  3. ^ Ejnar Hertzsprung : Remarks on the period of U Leporis . In: Bulletin of the Astronomical Institutes of the Netherlands . 2, July 1923, p. 18. bibcode : 1923BAN ..... 2 ... 18H .