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<\/p>\nThe newest habitable module for the International Space Station (ISS), Nauka, has arrived at the Baikonur Cosmodrome in Kazakhstan for final preparations before launch. The module\u2019s launch \u2013 which has been delayed for more than 13 years \u2013 will mark the resumption of Station expansion.<\/p>\n
Nauka is currently scheduled to launch on a Proton-M rocket in April 2021 and will be attached to the ISS at the location where the Pirs Docking Compartment is currently located.
\nNauka\u2019s history<\/b><\/p>\n
The module that would become Nauka \u2013 Russian for \u201cScience\u201d \u2013 was first constructed as the backup to the currently-on-orbit Zarya module. As such, both are of a similar design called the \u201cFunctional Cargo Block\u201d (FGB).<\/p>\n
The FGB design traces its roots to the Soviet TKS spacecraft that was designed in the 1960s to serve as a crew and cargo resupply vehicle for the Soviet Union\u2019s Salyut space stations. It was comprised of two parts \u2013 the VA spacecraft and Functional Cargo Block \u2013 both of which could also operate independently.<\/p>\n
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Cutaway diagram of the TKS spacecraft. The pressurized volume is outlined in bold. The cylindrical FGB is visible on the left and center, while the conical VA and maneuvering system is visible on the right. Credit: NASA<\/p>\n
The VA spacecraft itself was initially designed as a lunar crew vehicle \u2013 similar to the Apollo Command Module. It would have carried up three crew members during launch and landing and was notable in that it was intended to be reused -although this was only demonstrated once.<\/p>\n
For lunar missions, the VA would have launched on a Proton rocket with a service module attached to allow for a longer mission. However, this configuration was shelved in favor of the Soyuz 7K-L1 design (also known as \u201cZond\u201d), which went on to fly 12 times. After it was rejected for the Soviet lunar program, the VA was repurposed to become part of the TKS spacecraft.<\/p>\n
The Functional Cargo Block under this design served as a service and storage module. It featured a spacious pressurized volume in its center, meant for cargo storage and docking equipment. On the outside of the FGB were fuel tanks, maneuvering engines, solar arrays, and docking port.<\/p>\n
The TKS flew four times and docked to Salyut stations three times. None of those missions were crewed.<\/p>\n
Space Shuttle models (adsbygoogle = window.adsbygoogle || []).push({});<\/p>\n Following the cancellation of the TKS, the Soviet space program soon realized the other possibilities the FGB design could offer.<\/p>\n In 1987, the Kvant-1 module was launched to the Mir space station. Rather than having its own control system, it was delivered to the station by a Functional Service Module \u2013 derived from the FGB.<\/p>\n<\/p>\n