U Cephei

astronomy

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Last updated

July 14, 2026

Quick Summary

U Cephei is a classic example of an eclipsing binary star system. In such systems, one star transfers matter to its companion. Spectroscopic evidence shows gas streams flowing from a more evolved star to its hotter, more massive companion. This process can lead to instabilities and eventual explosions, such as novas or supernovas. U Cephei is specifically noted for this mass transfer phenomenon, where the more evolved star swells and its outer envelope is pulled towards the smaller star. This interaction is a key aspect of understanding stellar evolution in binary systems.1

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Explosive variables
U Cephei is a classic example of such a system for which spectroscopic evidence shows streams of gas flowing from the more highly evolved star to the hotter companion, which is now the more massive of the two. Eventually, the latter will also leave the…
Read More
U Cephei is a classic example of such a system for which spectroscopic evidence shows streams of gas flowing from the more highly evolved star to the hotter companion, which is now the more massive of the two. Eventually, the latter will also leave the…
Read More