<P> Nauka (Russian: Нау́ка; lit . "science"), also known as the Multipurpose Laboratory Module (MLM) or FGB - 2 (Russian: Многофункциональный лабораторный модуль, МЛМ), is the major Russian laboratory module . It was scheduled to arrive at the station in 2014, docking to the port that was occupied by the Pirs module . Due to deterioration during many years spent in storage, it proved necessary to build a new propulsion module, and the launch date was postponed to 2018 . Before the Nauka module arrives, a Progress spacecraft will remove Pirs from the station and deorbit it to reenter over the Pacific Ocean . Nauka contains an additional set of life support systems and attitude control . Originally it would have routed power from the single Science - and - Power Platform, but that single module design changed over the first ten years of the ISS mission, and the two science modules, which attach to Nauka via the Uzlovoy Module, or Russian node, each incorporate their own large solar arrays to power Russian science experiments in the ROS . </P> <P> Nauka's mission has changed over time . During the mid-1990s, it was intended as a backup for the FGB, and later as a universal docking module (UDM); its docking ports will be able to support automatic docking of both spacecraft, additional modules and fuel transfer . Nauka has its own engines . Like Zvezda and Zarya, Nauka will be launched by a Proton rocket, while smaller Russian modules such as Pirs and Poisk were delivered by modified Progress spacecraft . Russia plans to separate Nauka, along with the rest of the Russian Orbital Segment, to form the OPSEK space station before the ISS is deorbited . </P> <P> The Uzlovoy Module (UM), or Node Module is a 4 - metric - ton ball - shaped module that will allow docking of two scientific and power modules during the final stage of the station assembly, and provide the Russian segment additional docking ports to receive Soyuz MS and Progress MS spacecraft . UM is due to be launched in late 2018 . It will be integrated with a special version of the Progress cargo ship and launched by a standard Soyuz rocket . Progress would use its own propulsion and flight control system to deliver and dock the Node Module to the nadir (Earth - facing) docking port of the Nauka MLM / FGB - 2 module . One port is equipped with an active hybrid docking port, which enables docking with the MLM module . The remaining five ports are passive hybrids, enabling docking of Soyuz and Progress vehicles, as well as heavier modules and future spacecraft with modified docking systems . The node module was conceived to serve as the only permanent element of the future Russian successor to the ISS, OPSEK . Equipped with six docking ports, the Node Module would serve as a single permanent core of the future station with all other modules coming and going as their life span and mission required . This would be a progression beyond the ISS and Russia's modular Mir space station, which are in turn more advanced than early monolithic first generation stations such as Skylab, and early Salyut and Almaz stations . </P> <P> Science Power Modules 1 & 2 (NEM - 1, NEM - 2) (Russian: Нау́чно - Энергетический Модуль - 1 и - 2) </P>

The international space station is designed to let astronauts stay there for about how long