A Russian Soyuz spacecraft carrying two cosmonauts and a veteran NASA astronaut blasted off from Kazakhstan Friday, chased down the International Space Station and glided to a smooth automated docking, boosting the lab’s crew back to six.

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.

Liftoff of a previously-flown Falcon 9 rocket is set for 6:27 p.m. EDT (2227 GMT) Thursday from NASA’s Kennedy Space Center in Florida, the first time SpaceX has reused one of its first stage boosters on a second mission. Ground crews face a tight timeline to ready the rocket and the SES 10 communications satellite in time for a Thursday launch attempt.