The star Alpha Virginis, magnitude 1.0. It is a spectroscopic binary consisting of a pair of B-type stars elongated by gravity so that the received light varies every 4 days as the pair orbit each other, although the amplitude is less than 0.1 mag. In addition, the primary is a variable of the Beta Cephei class, with a period of 0.17 days. Spica lies 250 l.y. away.
Subjects: Astronomy and Astrophysics.