Epsilon Carinae

Epsilon Carinae A/B

Artistic rendering of Avior binary system (Epsilon Carinae)
Observation data
Epoch J2000      Equinox J2000
Constellation Carina
Right ascension 08h 22m 30.8s
Declination −59° 30′ 35″
Apparent magnitude (V) 1.86 (~2.3 / ~3.3)
Characteristics
Spectral type K3 III/B2 V
U−B color index 0.19
B−V color index 1.20
Variable type Eclipsing
(suspected)
Astrometry
Radial velocity (Rv) 2 km/s
Proper motion (μ) RA: −25.34 mas/yr
Dec.: 22.72 mas/yr
Parallax (π) 5.16 ± 0.49 mas
Distance 630 ± 60 ly
(190 ± 20 pc)
Absolute magnitude (MV) −4.58
Details
Mass 10/8 M
Radius 170/4.5 R
Luminosity 10000/~3,000 L
Temperature 4,100/24,000 K
Other designations
Avior, HR 3307, CD−59°1032, HD 71129, SAO 235932, FK5 315, HIP 41037, GC 11463, CCDM J08225-5931
Database references
SIMBAD data

Epsilon Carinae (ε Car, ε Carinae) is a star in the constellation Carina. At apparent magnitude +1.86 it is one of the brightest stars in the night sky, but is not visible from the northern hemisphere.

It is also known by the name Avior, but this is not a classical name. It was assigned to the star by Her Majesty's Nautical Almanac Office in the late 1930s during the creation of The Air Almanac, a navigational almanac for the Royal Air Force. Of the fifty-seven navigation stars included in the new almanac, two had no classical names: Epsilon Carinae and Alpha Pavonis. The RAF insisted that all of the stars must have names, so new names were invented. Alpha Pavonis was named "Peacock", a translation of Pavo, whilst Epsilon Carinae was called "Avior".[1]

In Chinese, 海石 (Hǎi Dàn), meaning Sea Rock, refers to an asterism consisting of ε Carinae, ι Carinae, HD 83183, HD 84810 and υ Carinae .[2] Consequently, ε Carinae itself is known as 海石一 (Hǎi Dàn yī, English: the First Star of Sea Rock.)[3]

Epsilon Carinae is a binary star located 630 light years away from the Earth. The primary component is a dying orange giant of spectral class K0 III, and the secondary is a hot hydrogen-fusing blue dwarf of class B2 V. The stars regularly eclipse each other, leading to brightness fluctuations on the order of 0.1 magnitudes.

Notes

  1. ^ Sadler, D.H.: "A Personal History of H.M. Nautical Almanac Office", page 46. Edited and privately published by Wilkins, G.A., 1993
  2. ^ (Chinese) 中國星座神話, written by 陳久金. Published by 台灣書房出版有限公司, 2005, ISBN 978-986-7332-25-7.
  3. ^ (Chinese) 香港太空館 - 研究資源 - 亮星中英對照表, Hong Kong Space Museum. Accessed on line November 23, 2010.