Delta Cephei's hidden companion
Tuesday, May 12, 2015 - 06:00
in Astronomy & Space
To measure distances in the universe, astronomers use cepheids, a family of variable stars whose luminosity varies with time. Their role as distance calibrators has brought them attention from researchers for more than a century. While it was thought that nearly everything was known about the prototype of cepheids, named Delta Cephei, a team of researchers at the University of Geneva (UNIGE), the Johns Hopkins University, and the European Space Agency (ESA), have now discovered that this star has a hidden companion. They have published an article about the discovery in The Astrophysical Journal.