Timeline
Three SPHERES vehicles were delivered to the International Space Station. The first vehicle, along with a limited supply of consumables and support equipment, arrived at the station aboard Progress flight ISS-21P, and single-vehicle tests and experiments began on May 18, 2006. The second vehicle arrived with a much larger supply of consumables aboard Space Shuttle flight STS-121. The final vehicle and consumable supply were delivered to the station on Space Shuttle flight STS-116.
On April 27, 2007, ISS Expedition 15 flight engineer Sunita Williams performed a series of test flights with the satellites.
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