Assembly of the International Space Station
[2] A number of smaller pressurized sections will be adjunct to them (Soyuz spacecraft (permanently 2 as lifeboats – 6 months rotations), Progress transporters (2 or more), the Quest and Pirs airlocks, as well as periodically the H-II Transfer Vehicle).
The Rassvet module on the ISS right now was originally supposed to be the on-ground dynamic testing mock-up of the now-cancelled Science Power Platform.
The Nauka science laboratory module contains new crew quarters, life support equipment that can produce oxygen and water, and a new galley.
The Nauka was originally supposed to be delivered to the ISS in 2007 but cost overruns and quality control problems delayed it for over a decade.
This potential problem with the Zvezda was made apparent when in October 2020 the toilet, oven, and Elektron all malfunctioned at the same time and the cosmonauts onboard had to make emergency repairs.
Although during the construction the station attitude may vary, when all four photovoltaic modules are in their definitive position the aft-forward axis will be parallel to the velocity vector.
The subsequent two and a half-year suspension of the U.S. Space Shuttle program, followed by problems with resuming flight operations in 2005, were major obstacles.
[citation needed] Between the Columbia disaster and the resumption of Shuttle launches, crew exchanges were carried out solely using the Russian Soyuz spacecraft.
Because the ISS had not been visited by a shuttle for an extended period, a larger than planned amount of waste accumulated, temporarily hindering station operations in 2004.
Requirements for stepping up the crew size included enhanced environmental support on the ISS, a second Soyuz permanently docked on the station to function as a second 'lifeboat', more frequent Progress flights to provide double the amount of consumables, more fuel for orbit raising maneuvers, and a sufficient supply line of experimental equipment.
Later additions included the Bigelow Expandable Activity Module (BEAM) in 2016, and numerous Russian components are planned as part of the in-orbit construction of OPSEK.
