Cepheid variable star with record period of pulsation discovered in Milky Way

Astronomers at the University of Warsaw in Poland discovered a new Cepheid variable star. The newly discovered star, designated OGLE-GD-CEP-1884, has the longest pulsation period known for any variable of its type in the Milky Way Galaxy, an article published on the arXiv preprint server says.

Photo: nasa.gov by NASA, ESA, the Hubble Heritage Team (STScI/AURA) and J. Green (University of Colorado, Boulder) is licensed under public domain

Cepheids are yellow giant and supergiant stars that change their brightness over time as a result of regular stellar pulsations. Given that their pulsation periods are closely related to their luminosity, astronomers use these stars to measure interstellar and intergalactic distances.

Classic Cepheids, also known as Type I Cepheids, pulsate with highly regular periods ranging from a few days to months.

The record-breaking classical Cepheid was identified using the Warsaw Telescope at Las Campanas Observatory in Chile as part of the Optical Gravitational Lensing Experiment (OGLE). The experiment is a long-term sky survey that involves regular photometric observations of about two billion stars in the Milky Way and Magellanic Clouds.