ISS First Module Launched
Russia launched the Zarya module - the first component of the International Space Station
November 20, 1998
Building a Home in Orbit
The International Space Station (ISS) began construction in orbit in November 1998 when the Russian module Zarya was launched. The first U.S. module, Unity, was added a month later. Over the next thirteen years, 42 assembly flights by the U.S. Space Shuttle and Russian Soyuz rockets added laboratory modules, solar arrays, docking ports, and living quarters. The station grew to the size of a football field, becoming the largest structure humans have ever put in space.
Life Aboard the Station
The first permanent crew arrived in November 2000, and the station has been continuously inhabited ever since. Crews of five to seven astronauts and cosmonauts from partner countries — including the United States, Russia, Japan, Canada, and European nations — live and work aboard for missions typically lasting six months. They conduct science experiments in biology, physics, and materials science that can only be done in microgravity. Daily life includes exercise routines to counter muscle loss, video calls with family, and occasional spacewalks to maintain the station's exterior.
A Symbol of International Cooperation
The ISS is often described as the most complex engineering project in history. It required fifteen nations to agree on technical standards, share costs, and work together across language and cultural barriers. Even during periods of political tension between the United States and Russia, cooperation on the station continued. The ISS is expected to operate into the 2030s, after which commercial space stations may take its place in low Earth orbit. Check our age calculator to see how old the ISS is today.