High Quality Content by WIKIPEDIA articles! Zvezda (Russian: Звезда, meaning "star"), DOS-8, also known as the Zvezda Service Module, is a component of the International Space Station (ISS). It was the third module launched to the station, and provides all of the station`s life support systems, some of which are supplemented in the USOS, as well as living quarters for two crew members. It is the structural and functional center of the Russian portion of the station - the Russian Orbital Segment.