It's the third flight of the Crew Dragon capsule since last May, and the first time an American capsule has been reused in decades. There are now more astronauts than beds on the space station.
Three NASA astronauts and one from Japan's space agency reached the ISS after a 27-hour flight following Sunday's liftoff from the Kennedy Space Center.
The docking came above China and Mongolia as the ISS was traveling at 17,000 mph. It docked 19 hours after the historic launch with NASA astronauts from the Kennedy Space Center.
If the weather holds, later today the space agency and the commercial spaceflight company will send two astronauts on a trip to the International Space Station.
When Doug Hurley launched aboard Atlantis on July 8, 2011, the future of human spaceflight from U.S. soil was uncertain. Nearly a decade later, the astronaut is piloting SpaceX's new Crew Dragon.
NASA and SpaceX plan to launch astronauts to the International Space Station on Wednesday. It'll be the first time a new kind of spacecraft has launched astronauts into orbit since the space shuttle.
After a flawless launch from Cape Canaveral, Fla., the crew capsule, loaded with 600 pounds of cargo for the station, was unable to reach its intended orbit, Boeing says.
Astronauts in the station opened Crew Dragon's hatch and entered the spacecraft on Sunday, in a significant moment for both Elon Musk's company and the future of commercial space exploration.
