V636 Scorpii is a multiple star system in the constellation Scorpius, 3,000 light years away. The primary is a Classical Cepheid (δ Cephei) variable and its visual magnitude varies from 6.4 to 6.9.
V636 Scorpii is a spectroscopic binary, and the fainter companion is thought to itself consist of two stars. The primary is a luminous yellow star and a δ Cephei variable. The less massive companion orbits every 3.6 years and is apparently a B9.5 main sequence star, but the dynamics of the system suggest that it may actually be a pair of stars is a close orbit.[9]
The Cepheid primary pulsates regularly with a period of 6.79671 days. It is a yellow-white supergiant or bright giant that is 5.6 times as massive as the Sun and 2,500 times as luminous.[4]
^ abcSamus, N. N.; Durlevich, O. V.; et al. (2009). "VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013)". VizieR On-line Data Catalog: B/GCVS. Originally Published in: 2009yCat....102025S. 1. Bibcode:2009yCat....102025S.