* Astronomy

The Unity connecting module was carried into orbit as the primary cargo of the Space Shuttle Endeavour on STS-88, the first Space Shuttle mission dedicated to assembly of the station. On December 6, 1998, the STS-88 crew mated the aft berthing port of Unity with the forward hatch of the already orbiting Zarya module. (Zarya was a mixed Russian-US funded and Russian-built component launched earlier aboard a Russian Proton rocket from Baikonur, Kazakhstan.) This was the first connection made between two station modules.
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