Page "Antares" Paragraph 7

Antares has a secondary companion star, Antares B, that changed from an angular separation of 3. 3 arcseconds in 1854 to 2. 86 arcseconds in 1990.

The last is equal to a projected separation of about 529 Astronomical Units ( AU ) at the estimated distance of Antares, giving a minimum value for the separation of the pair.

Spectroscopic examination of the energy states in the outflow of matter from the companion star suggest that it is about 224 AU behind the primary, giving a combined separation of about 574 AU.

The stellar classification of this star is B2. 5, with numerous spectral lines suggesting it has been polluted by matter ejected by Antares.

At magnitude 5. 5, it is only 1 / 370th as bright visually as Antares A, although it shines with 170 times the Sun's luminosity.