Akruks ( Alpha Southern Cross , lat. Alpha Crucis , abbr. Α Cru ) - the brightest star in the constellation Southern Cross . It is a multiple star with a magnitude of 0.77 m [3] and the thirteenth of the brightest stars [3] of the night sky. The proper name Akruks is made up of the Bayer designation α and the Latin name for the constellation Crux .
| Acrux AB | |||
|---|---|---|---|
| Star | |||
 The position of Akruks in the sky. | |||
| Observational data ( Age J2000.0 ) | |||
| Type of | Spectral double | ||
| Right ascension | |||
| Declination | |||
| Distance | 320 ± 20 St. years (98 ± 6 pc ) | ||
| Visible magnitude ( V ) | +0.77 + 1.40 / + 2.09 | ||
| Constellation | South Cross | ||
| Astrometry | |||
| Radial velocity ( R v ) | |||
| Own movement (μ) | RA: -35.37 mas per year Dec: -14.73 mas per year | ||
| Parallax (π) | 10.17 ± 0.50 mas | ||
| Absolute magnitude (V) | 0.56 | ||
| Specifications | |||
| Spectral class | B1v | ||
| physical characteristics | |||
| Weight | 14/10 M ☉ | ||
| Temperature | 28 000/26 000 K | ||
| Luminosity | 25 000/16 000 L ☉ | ||
| Orbit elements | |||
| Period ( P ) | 0.208 years | ||
| Semimajor axis ( a ) | 1.0 " | ||
| Eccentricity ( e ) | 0,0 | ||
| Inclination ( i ) | 0,0 ° v | ||
| |||
| Database Information | |||
| SIMBAD | data | ||
Physical Properties
Akruks is a three-star system located approximately 320 light years from the solar system . Two components of the system α 1 and α 2 (another designation: α Cru A and α Cru B ) are visually separated when observed through a telescope, the angular distance between them is 4 angular seconds. Components α 1 and α 2 have a visible magnitude of +1.40 m and +2.09 m , respectively. Both stars belong to class B and are in the main sequence . Their surface temperatures are about 28,000 and 26,000 K, respectively, and their luminosities are 25,000 and 16,000 times that of the Sun. α 1 and α 2 are located at about 430 AU from each other, which makes their movement barely noticeable. Both stars make a complete revolution around each other in more than 1,500 years.
α 1 itself is a spectrally binary star , with components about 14 and 10 times the mass of the solar and orbital periods of 76 days; they are at a distance of about 1 a. e. from each other. The mass of component α 2 and the brightness of component α 1 show that stars can explode in the future as supernovae . The weak component α 1 may become a massive white dwarf after the explosion.
Another component, Alpha Southern Cross C or α 3 Southern Cross, is a subgiant of class B4 and lies 90 arc seconds from the Acrox triple system. It is assumed that α 3 may be gravitationally coupled to Akruks. However, if she really was not far from Akruks, then she would be too bright for her class. This is probably just an optically binary star, lying beyond the gravitational interaction of the Akruks star, and most likely, twice as far from the Sun, in 640 light years (200 pc).
See also
- List of the brightest stars
Notes
- ↑ 1 2 Gontcharov G. A. Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system // Ast. Lett. / R. Sunyaev - Nauka , 2006 .-- Vol. 32, Iss. 11. - P. 759–771. - ISSN 1063-7737 ; 1562-6873 ; 0320-0108 ; 0360-0327 - doi: 10.1134 / S1063773706110065
- ↑ 1 2 3 4 Leeuwen F. v. Validation of the new Hipparcos reduction // Astron. Astrophys. - EDP Sciences , 2007. - Vol. 474, Iss. 2. - P. 653–664. - ISSN 0004-6361 ; 0365-0138 ; 1432-0746 ; 1286-4846 - doi: 10.1051 / 0004-6361: 20078357 - arXiv: 0708.1752
- ↑ 1 2 David Darling. Acrux (Alpha Crucis) . Date of treatment September 6, 2009. Archived on April 20, 2013.