U camelopardalis

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Star
U Camelopardalis
Shot of the Hubble Space Telescope's Advanced Camera for Surveys
Shot of the Hubble Space Telescope's Advanced Camera for Surveys
AladinLite
Observation
dates equinox :  J2000.0 , epoch : J2000.0
Constellation giraffe
Right ascension 03 h 41 m 48.18 s
declination + 62 ° 38 ′ 54.4 ″
Apparent brightness 11.0 mag
Typing
B − V color index (0.5) 
Spectral class C3.9-C6.4e (N5)
Variable star type SRB 
Astrometry
Radial velocity (−3.0 ± 4.4) km / s
parallax (1.64 ± 0.12)  mas
distance (2,000)  ly
(600)  pc
Proper movement 
Rec. Share: (4.47 ± 0.15)  mas / a
Dec. portion: (−3.34 ± 0.15)  mas / a
Physical Properties
Other names
and catalog entries
Bonn survey BD + 62 ° 596
Henry Draper Catalog HD 22611 [1]
Hipparcos catalog HIP 17257 [2]
SAO catalog SAO 12870 [3]
Tycho catalog TYC 4066-1219-1 [4]Template: Infobox star / maintenance / specification of the TYC catalog
2MASS catalog 2MASS J03414816 + 6238541 [5]
Other names U Camelopardalis, IRAS 03374 + 6229

U Camelopardalis ( U Cam ) is a semi-regularly changing carbon star .

The star is surrounded by a gas envelope with an expansion speed of 23 km / s. It has a dynamic age of around 700 years and was probably created within a few decades by modulating the rate of mass loss by a helium shell flash ("thermal pulse").

The distance from U Cam was estimated to be around 400 parsecs using the period-luminosity relation; it lies in the constellation Camelopardalis (Giraffe). Measurements of the Gaia mission using the parallax method show a distance of around 600 parsecs, which corresponds to 2000 light years ( Gaia DR2 ). Estimates of the effective temperature are between around 2500 and 3000 Kelvin.

North of U Cam, at a distance of a good 200 arcseconds, is the star BD + 62 ° 594 . Measurements of the angular distance and the position angle were published by Robert S. Ball as early as 1884. Due to the difference in radial velocities, it can now be ruled out that the two stars form a bound system. The supposed companion has an apparent visual brightness of 9.6 mag and belongs to the spectral class B8 V.

Web links

Individual evidence

  1. ↑ a b c d e U Cam. In: SIMBAD . Center de Données astronomiques de Strasbourg , accessed December 4, 2018 .
  2. ↑ a b U Cam. In: VSX. AAVSO, accessed December 4, 2018 .