Browsing: Cepheids

Cepheids, also known as Cepheid variables, are a type of pulsating star characterized by regular changes in brightness over a defined period. These stars are particularly significant in astronomy because their pulsation periods are directly related to their intrinsic luminosity, a relationship known as the “period-luminosity relation” or “Leavitt Law.” Discovered by Henrietta Swan Leavitt in the early 20th century, this relationship allows astronomers to determine the distance to Cepheids and, by extension, other astronomical objects, making them crucial “standard candles” for measuring cosmic distances. Cepheids are typically supergiant stars, many times more massive and luminous than the Sun, and they play a vital role in calibrating the cosmic distance scale, thereby enhancing our understanding of the size and expansion rate of the universe.