Adhara

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Double star
Adhara
Observation
dates equinox :  J2000.0 , epoch : J2000.0
AladinLite
Constellation Big dog
Astrometry
Radial velocity (+27.3 ± 0.9) km / s
parallax (7.57 ± 0.57) mas
Individual data
Names A; B.
Observation data:
Right ascension A. 6 h 58 m 37.5 s
B. 65837.76 h 58 m 37.7 s
declination A. 1714180.5−28 ° 58 ′ 19.5 ″
B. 1714176−28 ° 58 ′ 24 ″
Apparent brightness A. 1.5 mag
B.
Typing:
Spectral class A. B2 Iab:
Physical Properties:
radius A. (10.7 ± 1.5) R ☉
B.
Other names
and catalog entries
Bayer name ε Canis Majoris
Flamsteed name 21 Canis Majoris
Cordoba Survey CD-28 3666
Bright Star Catalog HR 2618 [1]
Henry Draper Catalog HD 52089 [2]
SAO catalog SAO 172676 [3]
Tycho catalog TYC 6535-3619-1 [4]
Hipparcos catalog HIP 33579 [5]
Further designations: Adhara, FK5 268

Template: Infobox double star / maintenance / single coordinates

Adhara is the name of the star ε (epsilon) Canis Maioris in the constellation Big Dog . The name (from arab.عذارى, DMG ʿaḏārā ) means "(the) virgins". He is one of the bright giants .

Adhara is a binary star system 470 light years away. The main star has an apparent brightness of +1.5 m and belongs to the spectral class B2. The +7.5 m bright companion star (the absolute brightness is -5 M ) is located at an angular distance of 7.5 " at a position angle of 161 degrees from the main rating.
Despite the relatively large angular distance, the system can only in large telescopes into individual stars be resolved because the main star outshines the approximately 250 times weaker companion to a high degree.

4 to 5 million years ago, Adhara was less than 40 light years from Earth and one of the brightest stars in the night sky . With an apparent brightness of -4 m , the star shone as brightly as Venus .

See also

Web links

Individual evidence

  1. ↑ JMMC Stellar Diameters Catalog - JSDC (Lafrasse +, 2010) (calculated from the data values ​​LDD and Plx)