Which rocket launched the Zarya and Zvezda ISS modules?

The Proton-K rocket launched both the Zarya and Zvezda modules of the International Space Station. This heavy-lift Soviet-designed vehicle was used for the station’s early Russian-built elements before being retired.

Zarya, the first ISS module, launched from Baikonur Cosmodrome on November 20, 1998. Although Russian-built and funded by the United States, it provided early power, propulsion, storage, and guidance functions. Zvezda followed on July 12, 2000, also launched by Proton-K, and became the station’s principal Russian service module and crew-living section.

Proton-K, also known as Proton 8K82K, was manufactured by Khrunichev. Its standard configuration used three stages powered by hypergolic nitrogen tetroxide and unsymmetrical dimethylhydrazine. The rocket made 310 launches before its final flight in 2012 and was replaced by the modernized Proton-M.

The wrong options reflect different launch traditions: Soyuz-U launched many crewed and cargo spacecraft, while Ariane 5 and Falcon 9 are associated with other missions and were not the launchers for these two ISS modules.