27 epic images show how SpaceX made history by flying NASA astronauts to and from the space station

For the last nine years, NASA relied on increasingly expensive Russian Soyuz rockets to ferry its astronauts to and from the space station

NASA TV microphones picked up Behnken telling his son: "Be good for mom. Make her life easy."

The astronauts couldn't hug their families because they had just spent two weeks in quarantine to ensure they didn't accidentally carry COVID-19 to the space station.

The program is NASA's solution to the void left by the space shuttles. It funded both SpaceX and Boeing to build human-grade commercial spaceships, but SpaceX got to its crewed flight first.

In a press briefing ahead of the launch, Behnken told Business Insider that he and Hurley had gained more insight into the ways the mission could fail "than any crew has in recent history, just in terms of understanding the different scenarios that are at play."

NASA had estimated a 1-in-276 chance that the mission would be fatal. Behnken said that they were "really comfortable" with those odds.

"I've spent 18 years working toward this goal, so it's hard to believe that it's happened," Musk added. "This is hopefully the first step on a journey towards civilization on Mars, of life becoming multiplanetary, a base on the moon, and expanding beyond Earth."

Their new crewmates — NASA astronaut Chris Cassidy and Russian cosmonauts Anatoly Ivanishin and Ivan Vagner — were waiting to welcome them.

They effectively claimed victory for SpaceX in a game of capture the flag that Barack Obama started when he developed the Commercial Crew Program.

After a night's rest for the astronauts (and several hours of maneuvering the spaceship), the Endeavour capsule fired its thrusters and pushed itself into Earth's atmosphere on Sunday.

SpaceX

That's because of the capsule's asymmetric design, which is necessary for the emergency-escape system that jettisons the capsule away if a launching rocket fails in midair. 

"If you rotate too much, then you could potentially catch the plasma in the super Draco escape thruster pods," Musk told Aviation Week's Irene Klotz in May, a few days before the launch. "We've looked at this six ways to Sunday, so it's not that I think this will fail. It's just that I worry a bit that it is asymmetric on the backshell."

"Maybe next time we shouldn't announce our landing zone," the SpaceX engineer Kate Tice said during NASA's live feed of the landing.

—Ivan Vagner (@ivan_mks63) August 2, 2020

In a statement to CBS, the Coast Guard said it warned boaters multiple times ahead of the splashdown with radio alerts and physical warnings, yet lacked an order to legally enforce a hazard zone.

"Numerous boaters ignored the Coast Guard crews' requests and decided to encroach the area, putting themselves and those involved in the operation in potential danger," the statement said.

That's because the Endeavour capsule can be shrouded in poisonous fumes after it plummets through Earth's atmosphere. 

The crowd "was not what we were anticipating," NASA Administrator Jim Bridenstine said in a briefing after the splashdown. 

"That's not something that is good," he added. "We need to make sure that we're warning people not to get close to the spacecraft in the future."

The team picked up a dangerous gas around the capsule called nitrogen tetroxide. They waited for it to clear before opening the spaceship's hatch.

The men were fine but found it difficult to stand after the splashdown. That's normal for ISS astronauts, since their bodies become accustomed to floating in space and suddenly have to work much harder to move against Earth's gravity.

A helicopter took Behnken and Hurley to dry land.

"When the space shuttles retired, when Doug took his final flight to wrap that up, I think it was a sad day for us," Behnken said. "There's something special about having that capability to launch and bring your own astronauts home."

Dave Mosher contributed reporting.