A SpaceX Crew Dragon capsule caught up with the International Space Station early Saturday and glided in for a picture-perfect docking, bringing four fresh astronauts to the outpost and setting the stage for four others to return to Earth next week aboard a second SpaceX ferry ship.
Completing a computer-orchestrated rendezvous that began Friday with a launch from the Kennedy Space Center, the "Crew-2" capsule approached the station from behind and below, looping up to a point directly ahead of the lab while both spacecraft streaked through space at more than 17,000 mph.
That's fast enough to cover more than 80 football fields in one second, but the rendezvous appeared to play out in slow motion as the Crew Dragon inched closer and closer with a precisely calculated, slightly different velocity.
Captured in spectacular clarity by high-definition cameras on the station, the Crew Dragon moved in for docking at the Harmony module's forward port at 5:08 a.m. ET, just a few feet away from a space-facing port where another Crew Dragon is docked.
After extensive leak checks to verify an airtight structural seal, hatches were opened, safety systems configured and Crew-2 commander Shane Kimbrough, Megan McArthur, European Space Agency astronaut Thomas Pesquet and Japanese flier Akihiko Hoshide floated into their new home in space.
They were welcomed aboard by Crew-1 astronauts Michael Hopkins, Victor Glover, Shannon Walker and Japanese astronaut Soichi Noguchi — launched to the lab last November — and Soyuz MS-18 commander Oleg Novitskiy, Pyotr Dubrov and Mark Vande Hei. They arrived April 9.
"We are happy eleven on #ISS," Noguchi tweeted. "Welcome back to home away from home for 6 months!!!!!!"
Crowded together for a brief welcome ceremony, the expanded crew was congratulated by NASA's acting administrator, Steve Jurczyk, who said "it is awesome to see the 11 of you on station. It's incredible."
"So congratulations," he said. "Also want to congratulate the NASA and SpaceX team for our third commercial crewed mission in less than a year. It was really cool during docking to see one Dragon docked on the zenith port and the other Dragon coming in."
The Crew-2 ship that carried Kimbrough and company to the station first flew last year in a piloted test flight that brought McArthur's husband, Robert Behnken, to the lab complex along with Douglas Hurley.
In another first, the Falcon 9 first stage booster that propelled the refurbished Crew-2 capsule into space is the same rocket that launched the Crew-1 Dragon to the station last year.
"We're just really excited to be here and be part of this historic mission with the two Dragons on board, first reuse of a capsule, first reuse of a booster," McArthur said. "It's just a tremendous achievement on behalf of our partner, SpaceX. So I want to congratulate and thank them. We're ready to get to work."
The Crew-2 astronauts are replacing Hopkins, Glover, Walker and Noguchi, who were launched to the station last November aboard the Crew-1 Dragon.
After a four-day "direct handover," familiarizing Kimbrough and his crewmates with station operations and safety procedures, the Crew-1 astronauts will undock from Harmony's upper port early Wednesday. Splashdown in the Gulf of Mexico south of Tallahassee, Florida, is expected at 12:40 p.m.