- After spending six days in space, Crew Dragon, a commercial spaceship for people designed by SpaceX, is coming back to Earth.
- Elon Musk, the founder of SpaceX, hinted that this will be the most challenging phase of the mission, called Demo-1.
- NASA TV and SpaceX will jointly broadcast live video and commentary of the return on Friday morning, and you can watch live below.
- Undocking coverage started at 2 a.m. ET, and landing coverage began at 7:30 a.m. Crew Dragon should splash into the Atlantic Ocean at 8:45 a.m.
- No astronauts are on board – just a dummy. But NASA says the demonstration mission is “critically important” to show that the vehicle is safe to fly.
Update: Crew Dragon successfully landed at 8:45 a.m. ET on Friday. Read our full coverage here.
The most nail-biting phase of Elon Musk’s spaceflight dress rehearsal for NASA is almost here.
Early on Friday, SpaceX – the rocket company founded by Musk – will attempt to fly its new seven-seat commercial spaceship called Crew Dragon back to Earth. You can watch the effort unfold live via the YouTube video player below.
SpaceX’s 14,000-pound, cone-shaped vehicle launched from Kennedy Space Center in Florida last Saturday morning. About 27 hours later, it docked with the International Space Station, a football-field-size orbiting laboratory where three crew members live and work.
Crew Dragon took no people into orbit – just a spacesuit-clad dummy called Ripley, 400 pounds of cargo, and a plush toy Earth. Still, NASA has described the spaceship’s demonstration mission, called Demo-1, as critical, because the agency hasn’t had its own way to get astronauts to and from space for nearly eight years.
“This is a critically important event in American history,” Jim Bridenstine, NASA’s administrator, told reporters last week in Florida. “We’re on the precipice of launching American astronauts on American rockets from American soil again for the first time since the retirement of the space shuttle in 2011.”
On Thursday at 12:39 a.m. ET, the space station crew closed the hatch for Crew Dragon and said goodbye.
“This is the beginning of the end of Crew Dragon’s stay at the International Space Station,” NASA’s mission control center in Houston said during a live broadcast.
Now the ship has to return to Earth in one piece.
Watch SpaceX’s Crew Dragon landing attempt live on NASA TV
NASA TV broadcast Crew Dragon’s departure from the space station around 2 a.m. ET on Friday. The spaceship departed at 2:31 a.m., setting it up for a de-orbit and landing attempt.
NASA and SpaceX’s joint live coverage started at 7:30 a.m.
Below this feed, we’ve outlined what to expect and when from the broadcast.
When Crew Dragon undocked from the ISS, the spacecraft briefly fired its engines to push away from the space station. It then reoriented itself for coming home with three additional blasts of its thrusters.
SpaceX’s ship spent the next five or so hours orbiting Earth. The goal was to put Crew Dragon over the exact spot to splash down in the ocean about 230 miles east of Kennedy Space Center. Along the way, the ship popped off, or jettisoned, its trunk (which wasn’t needed anymore), allowing the gumdrop-shaped capsule to journey back to Earth.
NASA’s live broadcast picked up around 7:30 a.m. to show this landing phase. Around 7:53 a.m., SpaceX began a 15-minute firing of Crew Dragon’s thrusters to de-orbit, or slow down the spacecraft, causing it to drop from the sky. After this firing, the ship is expected to flip 180 degrees, with its bottom end, or back-shell, oriented first.
Crew Dragon should reach hypersonic speeds of nearly 20,000 mph – about 25 times the speed of sound – in the planet’s thin outer atmosphere, generating blisteringly hot plasma along the back-shell. A heat-shield liner should burn up, insulating and protecting Crew Dragon (and its dummy passenger) from being destroyed by the forces of atmospheric reentry.
Musk expressed some reservations about this phase during a press conference after Crew Dragon’s launch.
“I see hypersonic reentry as probably my biggest concern, just because of the asymmetric back-shell,” Musk said.
He was referring to the fact that Crew Dragon’s shape is not a smooth cone, like SpaceX’s cargo spaceship, Dragon 1. That’s because Crew Dragon, also called Dragon 2, has a rocket-powered escape system built into its hull; in case anything goes wrong during a launch, it can try to fly away.
“You’ve got the launch escape thruster pods. That could potentially cause a roll instability on reentry, but I think it’s unlikely, ” Musk said.
In other words, the force of air rushing past the asymmetric capsule might cause it to roll. That could expose unprotected parts of its hull or cause the spacecraft to spin so fast that any would-be passengers would get knocked out or injured.
“We’ve run simulations 1,000 times, but this is a possibility,” Musk added.
Once Earth’s atmosphere slows Crew Dragon to hundreds of miles per hour, the vehicle will deploy two drogue parachutes, followed by four larger parachutes, to further decelerate the capsule.
Musk hinted that that would also be a risky moment for the Demo-1 mission, since this hardware is different from what’s used in SpaceX’s cargo spaceship.
“The parachutes are new,” he said. “Will the parachutes deploy correctly? And then will the system guide Dragon 2 to the right location and splash down safely?”
If all goes well, the capsule should splash down into the ocean at 8:45 a.m. SpaceX crews waiting in boats will then try to recover the capsule as quickly as possible.
Why NASA needs Crew Dragon to be safe
SpaceX’s Crew Dragon is part of a larger NASA program called Commercial Crew.
NASA is paying SpaceX about $US2.6 billion to develop the new ship and launch six operational missions to the space station. The space agency has also awarded Boeing roughly $US4.2 billion to develop a space capsule for humans, called the CST-100 Starliner.
If SpaceX’s Demo-1 mission succeeds, it will move on to an in-flight escape test this spring. After that, NASA may clear SpaceX to launch the astronauts Bob Behnken and Doug Hurley, who would be the company’s first human passengers, on a Demo-2 mission as soon as July. Boeing is expected to fly its first astronauts as early as August.
SpaceX boat crews are expected to locate and pick up the spaceship with a special recovery vessel in an hour, though it may take a day to carry it back to port. Once Crew Dragon is back on dry land, the vehicle will be unpacked, its data downloaded, and its ship scrutinised for safe performance – especially the data gathered by sensors on Ripley, the crash-test dummy.
“We’ve done tons of water-landing testing, parachute testing – all of these individual pieces. But actually having a reentry with Ripley in the seat, in the position, is critical,” Kathryn Lueders, the manager of NASA’s Commercial Crew Program, previously told Business Insider. “We’ve instrumented the crap out of this vehicle.”
This story has been updated with new information. It was originally published on March 7, 2019.