On this day in 2000, the first residential crew arrives aboard the International Space Station. The arrival of Expedition 1 marked the beginning of a new era of international cooperation in space and of the longest continuous human habitation in low Earth orbit, which continues to this day.
The space agencies of the United States, Russia, Canada, Japan and Europe agreed to cooperate on the ISS in 1998, and its first components were launched into orbit later that year. Five space shuttle flights and two unmanned Russian flights delivered many of its core components and partially assembled the space station. Two Russians, Yuri Gidzenko and Sergei Krikalev, accompanied by NASA’s Bill Shepherd, were selected as the crew of Expedition 1.
The trio arrived at the ISS on a Russian Soyuz rocket launched from Kazakhstan. Unlike all subsequent missions, Expedition 1’s tasks consisted mostly of constructing and installing various components and activating others. This was sometimes easier said than done: the crew reported taking over a day to activate one of the station’s food warmers. Throughout their time in space, they were visited and resupplied by two unmanned Russian rockets and three space shuttle missions, one of which brought the photovoltaic arrays, giant solar panels, which provide the station with most of its power. Shepherd, Gidzenko and Krikalev became the first humans to adjust to long-term life in low orbit, circling the Earth roughly 15.5 times a day and exercising at least two hours a day in order to offset the muscle atrophy that occurs in low gravity.
On March 10, the space shuttle Discovery brought three new residents to relieve Expedition 1, who landed back on Earth at the Kennedy Space Center on March 21. Since then, humans have continuously resided on the ISS, with plans to continue until at least 2030. 236 people from 18 nations have visited the station and a number of new modules have been added, many for the purpose of research into biology, material sciences, the feasibility of further human space travel and more.
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