The Period-Luminosity Relation: A Historical Review

In some ways astronomers are like small children.The high adventure, the furor and excitement they create among themselves is not greatly cared about or understood outside, at least in any immediate way.Of all the discoveries of ground-based astronomy in this century, only the smallest handful can claim to have made the front-page headlines of the world's newspapers.One such instance came in 1952, when the headlines cried the news that the universe was at least twice as big as hitherto believed.To astronomers, the event signaled a turning point in the histoiy of the cepheid periodluminosity relation.It was the revelation of a major error which had gone undetected in forty years' work on this subject.The story is an