Alpha Pavonis

from Wikipedia, the free encyclopedia
Star
peacock (α pavonis)
AladinLite
Observation
dates equinox :  J2000.0 , epoch : J2000.0
Constellation peacock
Right ascension 20 h 25 m 38.86 s
declination -56 ° 44 ′ 6.3 ″
Apparent brightness 1.94 likes
Typing
B − V color index −0.20 
U − B color index −0.71 
R − I index −0.16 
Spectral class B2 IV
Astrometry
Radial velocity (+2.0 ± 0.9) km / s
parallax (18.24 ± 0.52)  mas
distance (179 ± 5)  ly
(54.8 ± 1.6)  pc  
Visual absolute brightness M vis approx. −1.8 mag
Proper movement 
Rec. Share: (+6.90 ± 0.44)  mas / a
Dec. portion: (−86.02 ± 0.32)  mas / a
Physical Properties
Dimensions 5 to 6  M ☉
radius 4.4  R ☉
Luminosity

2100  L ☉

Effective temperature 18 700  K
Other names
and catalog entries
Bayer name α Pavonis
Cordoba Survey CD −57 ° 7968
Bright Star Catalog HR 7790 [1]
Henry Draper Catalog HD 193924 [2]
Hipparcos catalog HIP 100751 [3]
SAO catalog SAO 246574 [4]
Tycho catalog TYC 8785-1898-1 [5]
2MASS catalog 2MASS J20253886-5644062 [6]
Other names FK5  764 • CPD −57 ° 9674
annotation
  1. ↑ roughly estimated from apparent brightness and distance

α Pavonis (Alpha Pavonis) is the brightest star in the constellation Peacock . It has an apparent magnitude of 1.94 mag and is only visible south of the 32nd degree north latitude. It belongs to the spectral class B2 IV, which characterizes it as a blue subgiant . Its distance is about 180  light years . α Pavonis is a spectroscopic binary star with an orbital period of 11.8 days, from which one can conclude that the two components are only 0.21 AU away .

α Pavonis is also called peacock . This is not a classic name, but the name is of modern origin: it was given to α Pavonis in the late 1930s when a navigation almanac was being drawn up for the Royal Air Force . Of the 57 stars in the new almanac, two - ε Carinae and α Pavonis - had no traditional names, so new names - Avior and (after the constellation) Peacock - were invented for them.

The IAU has the proper name on July 20, 2016 Peacock defined as standardized proper name for this star.

See also

Web link

Individual evidence

  1. ↑ a b c Hipparcos catalog (ESA 1997)
  2. ↑ a b c Bright Star Catalog
  3. ↑ a b c Hipparcos, the New Reduction (van Leeuwen, 2007)
  4. ^ DH Sadler: "A Personal History of HM Nautical Almanac Office", p. 46. Ed. By GA Wilkins, 1993.
  5. ↑ Bulletin of the IAU Working Group on Star Names, No. 1, July 2016. (PDF) Retrieved November 9, 2016 (English, 184 KiB).