So, once a star’s temperature and luminosity are known, its size is easily calculated. Stars emit all colors of the rainbow, to varying degrees.

Betelgeuse, one of the brightest stars in the night sky, may not be alone. And its potential companion may be responsible for ...

Sizing up a star “Knowing the size of a star is of overall importance,” said Jamie Holder, associate professor in UD’s Department of Physics and Astronomy and a co-author of the study. “How big and ...