SpaceX's first operational human mission for NASA is set to launch from the Kennedy Space Center on Sunday.
The crew includes three NASA astronauts and a veteran Japanese astronaut.
NASA astronaut Shannon Walker is set to become the first woman ever to fly in a commercial spacecraft.
Visit Business Insider's homepage for more stories.
The demonstration phase is over.
On Sunday evening, SpaceX's first operational human mission for NASA, called Crew-1, will take off from the Kennedy Space Center in Florida. The crew consists of three NASA astronauts — Shannon Walker, Mike Hopkins, and Victor Glover — as well as Japan Aerospace Exploration Agency astronaut Soichi Noguchi.
After roughly 27 hours in flight, the Crew Dragon spaceship carrying the four astronauts will dock to the International Space Station, where NASA astronaut Kathleen Rubins and two Russian cosmonauts, Sergey Ryzhikov and Sergey Kud-Sverchkov, will be waiting to greet them.
The Crew-1 astronauts plan to stay on the ISS for the standard six months. During that time, they'll conduct space walks, do science experiments, and work on regular station maintenance.
The mission was initially, though tentatively, scheduled to launch in late September. But it was delayed twice in order to better coordinate with other ISS crew rotations, then again because of a problem with a rocket engine discovered during a test launch.
All systems are now ready to ferry the astronauts into space this weekend, but that's assuming the weather is favorable. Although Saturday was previously the target for lauch, it was pushed to Sunday at 7:27 p.m. ET due to weather issues.