... Stars . ... Cepheid variable stars have been known since the 18th century. ... Regularly brightening to a peak over days, weeks or months before fading these variable stars were remarkable curiosities to astronomers in past centuries.€а The term Cepheid is taken from the star Delta Cephei in the constellation of Cepheus, which was identified as variable€а in 1784 by the teenaged prodigy John Goodricke (1764-96). ... Tweets that mention Cepheids: Inconstant Stars which break the rules | ...