Private astronauts dock and then crowd onto the space station

The largest orbiting laboratory in the sky just got a lot more crowded.

The Axiom Space mission, the first all-private astronaut expedition to the International Space Station, made its arrival Saturday morning. While the ISS was flying 250 miles smack-dab above the Atlantic Ocean, private astronauts Michael Lopez-Alegria, Larry Connor, Eytan Stibbe, and Mark Pathy successfully docked the SpaceX Crew Dragon spacecraft and opened the hatch at 10:13 a.m. ET.

Perhaps a new group photo — showing some spaceflight-lagged and cabin-fever-weary faces — says it all.

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The Axiom crew will spend 10 days aboard the space station conducting scientific experiments using the lab's unique microgravity environment and participating in other commercial activities.

The mission will earn its place in history for expanding the definition of "astronaut." For decades, that title was reserved for government space pilots and crew. More recently, uber-rich space tourists riding the likes of Blue Origin, SpaceX, and Virgin Galactic have received the distinction of breaching Earth's atmosphere.

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With this new voyage comes a third possible description: Someone privately trained and launched into space to perform commercial scientific research.

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"It's important to address the difference between space tourists and private astronauts," said Larry Connor, the mission's pilot, during a news conference a week ago. "Our feeling is with the space tourists, they'll spend 10 or 15 hours training for five to 10 minutes in space — and by the way, that's fine. In our case, depending upon our role, we've spent anywhere from 750 to over 1,000 hours training."

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With the four Axiom astronauts on board, the space station now has a party of 11. That's nearly double the capacity the space station was designed to support: a crew of six, according to NASA (though the station can temporarily support other visitors, too). Now, imagine that the space station is only about the size of a five-bedroom home.

Before the official public broadcast began, the crew had to reorient the camera to fit all its space station residents in the frame, a mission broadcast commentator said.

But it's not a record. The most people to stay on the space station at one time is a baker's dozen. The occupancy rose to 13 people three times during the Space Shuttle program: the STS-127 in July 2009, STS-128 in August 2009, and STS-131 in April 2010.

Other current occupants include three NASA astronauts, Thomas Marshburn, Raja Chari, and Kayla Barron; one European Space Agency astronaut, Matthias Maurer; and three Roscosmos cosmonauts, Oleg Artemyev, Sergey Korsokov, and Denis Matveev.

What were the newcomers' reactions to the views from their new digs?

"One by one, I could hear them say, 'expletive deleted' as soon as they looked out the window, literally every single one of them, and I just smiled a little bit," Lopez-Alegria, the Axiom mission commander, said. "And then when I got my turn to look at it, same expletive. It's just an amazing experience."

Guess you'll just have to use your imagination.