Key Takeaways:
- The International Space Station (ISS) assembly commenced with the launch of the Russian-built Zarya Control Module on November 20, 1998, followed by the U.S.-built Unity Module, delivered by Space Shuttle *Endeavor*'s STS-88 mission on December 4.
- The STS-88 crew initiated on-orbit construction by attaching the Unity Module to *Endeavor*'s docking system on December 5, subsequently using a robotic arm to retrieve and connect Zarya to Unity the following day.
- After module connection, astronauts completed communications assembly to enable Houston's access, and the module's systems were activated on December 7.
- The initial human entry into the assembled ISS occurred on December 10, led by mission commander Robert Cabana and cosmonaut Sergei Krikalev.
The first module of the International Space Station (ISS), the Russian-built Zarya Control Module, was launched on Nov. 20, 1998. Two weeks later, on Dec. 4, the STS-88 mission launched on Space Shuttle Endeavor with the Unity Module, the first U.S.-built piece. The 12.8-ton component would be the crew’s living and working quarters, while Zarya was the command center and docking area.
Delivering this second component also meant beginning the construction of the ISS in space. The STS-88 crew attached the Unity Module to Endeavor’s docking system on Dec. 5. The next day, they used a 50-foot-long robotic arm to retrieve Zarya from orbit, and connected the two modules. The astronauts then completed communications assembly, allowing Houston to access the station, and the module’s systems were activated on Dec. 7. On Dec. 10, astronauts entered the ISS for the first time, as mission commander Robert Cabana and Russian cosmonaut Sergei Krikalev (a member of the STS-88 crew) led the way.
