NASA and Roscosmos, the Russian space agency, have agreed to extend astronaut Peggy Whitson’s stay aboard the International Space Station by three months to enable uninterrupted research aboard the orbital laboratory during a period when Russia is temporarily reducing its crew complement, the U.S. space agency said Wednesday.

Three days after a trio of space station fliers returned to Earth, a Russian cosmonaut, a German flight engineer and a NASA physician-astronaut rocketed into orbit aboard another Soyuz spacecraft Wednesday, setting off after the lab complex in the first step of a two-day rendezvous.

SpaceX’s Falcon 9 rocket will go from the Kennedy Space Center to low Earth orbit in 10 minutes Saturday with a Dragon capsule heading for the International Space Station carrying nearly 5,500 pounds of supplies and experiments.