Crew Dragon
SpaceX’s Crew Dragon is docked to the International Space Station. (NASA TV via YouTube)

SpaceX’s Crew Dragon spaceship docked with the International Space Station for the first time today, marking a successful uncrewed rehearsal of the procedure that astronauts will go through when they make their first arrival with the next flight.

The 27-foot-long spacecraft made contact with a docking adapter on the space station’s Harmony module at 2:51 a.m. PT, as the station flew 250 miles above the Pacific Ocean just north of New Zealand. That “soft docking” was the first step in an hours-long procedure to latch the Crew Dragon securely to the station, hook up power and data connections, and clear the way for hatch opening.

“Congratulations to all of the teams on a successful docking,” NASA astronaut Anne McClain radioed from the station. The news was greeted with cheers at SpaceX’s headquarters in Hawthorne, Calif.

Hours later, McClain and her two space station crewmates, Canada’s David Saint-Jacques and Russia’s Oleg Kononenko, donned protective masks — just in case noxious gases had built up inside the Dragon — and unlatched the spacecraft’s door at 5:07 a.m. PT. “Houston, Station: Dragon hatch opened,” McClain reported.

The astronauts then floated inside to take air samples and check out the scene.

No astronauts were riding the Crew Dragon for this flight. Instead, a spacesuit-wearing, sensor-laden mannequin nicknamed Ripley was placed in one of the seats to document what people would hear and feel during future trips. (The nickname was inspired by Sigourney Weaver’s character in the “Alien” sci-fi movies.)

The gumdrop-shaped craft also contained about 400 pounds of supplies and equipment, including a little plush toy shaped in the form of a smiling Planet Earth.

“Ripley and Earth both look like they enjoyed their trip up here,” McClain joked.

During a space-to-ground video ceremony celebrating the docking, McClain said the Crew Dragon’s trip served as a reminder that people from different nations “can be united by a cause that is not based on fear, threat or a common enemy, but rather on a bold endeavor, an insatiable curiosity to go beyond what is known, and to do what has never been done.”

“On behalf of Ripley, Little Earth, myself and our crew, welcome to the Crew Dragon. … These amazing feats show us not how easy our mission is, but how capable we are of doing hard things,” she said. “Welcome to the new era in spaceflight.”

Today’s docking, at the same port that was once used for space shuttle hookups, came about 27 hours after the Crew Dragon’s launch from Florida, on an uncrewed maiden voyage aimed at demonstrating that all of its systems will be safe for crewed flights.

Cargo versions of the Dragon have flown to the station 16 times since 2012, but the Crew Dragon represents a significant upgrade. While cargo Dragon spacecraft have been pulled in for their berthing with the station’s robotic arm, the Crew Dragon is built to guide itself autonomously to its hookup. Humans would need to take control only to override the software system in the event of a glitch.

The Crew Dragon’s autonomous capability caused some concern among Russian space officials in advance of today’s rendezvous. They worried that if the vehicle’s computer malfunctioned, the Dragon might have crashed into the station — much as a Russian Progress cargo craft crashed into the Mir space station in 1997.

To address such concerns, the space station’s three crew members were put on standby to retreat into their Soyuz lifeboat if necessary. Also, the Crew Dragon’s approach procedure included a test to demonstrate that the crew could issue commands to have the capsule back away from a standoff distance of about 140 meters (460 feet).

The Dragon passed all of its pre-docking tests, clearing the way for the docking.

Over the next several days, the crew will check out the onboard systems, unload cargo and get the Dragon ready for its return flight.

On the night of March 7-8, the spacecraft is scheduled to back away from its port on the station, descend through the atmosphere, open its parachutes and splash down into the Atlantic Ocean. A recovery team will be dispatched to pick up the capsule and check out how Ripley fared.

The current schedule calls for NASA astronauts Doug Hurley and Robert Behnken to take their seats on the next Crew Dragon demonstration flight in July. That schedule may slip, however, depending on how much more the Dragon needs to be tweaked after the uncrewed test flight.

Boeing, meanwhile, continues work on a different type of space taxi known as the CST-100 Starliner. The Starliner is currently due to make its first uncrewed test flight no earlier than April, and its first crewed flight no earlier than August.

Both companies have received billions of dollars from NASA to develop spacecraft capable of transporting astronauts safely to and from the station. Getting those spacecraft flying would mark the restoration of a U.S. crew-launching capability that was lost when the space shuttle fleet was retired in 2011.

Since that time, NASA has had to buy seats on Russian Soyuz spacecraft for crew rotations, at a cost that has escalated to more than $80 million per seat. NASA and the Russians are discussing one last purchase, just to make sure U.S. astronauts have access to the station even if the start of space taxi service has to be delayed.

SpaceX’s successful launch drew notice from President Donald Trump on Saturday. “We’ve got NASA “rocking” again,” Trump tweeted. “Great activity and success. Congrats to SPACEX and all!”

“Thank you on behalf of SpaceX,” CEO Elon Musk tweeted in reply. “Also, thank you to NASA, without whom this would not be possible.”

Here are a few of the top tweets from the docking sequence:

This is an updated version of a report that was first published at 4:30 a.m. PT March 3.

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