Acrobat, Astronauts Dock At Space Station

This story was updated at 10:13 a.m. EDT.

Two new crewmembers and a space tourist arrived at the International Space Station Friday.

NASA astronaut Jeffrey Williams, Russian cosmonaut Maxim Suraev, and Canadian space tourist Guy Laliberte docked at the orbital outpost at 4:35 a.m. EDT (0835 GMT).

Williams and Suraev are beginning a six-month tour of duty on the station as Expedition 21 and Expedition 22 crewmembers. Laliberte, a billionaire acrobat who founded the world-famous Cirque du Soleil circus troupe, paid about $35 million to the Russian Federal Space Agency for his 12-day space jaunt.

The trio lifted off on the Russian-built Soyuz TMA-16 spacecraft Wednesday from the Baikonur Cosmodrome in Kazakhstan.

Upon arrival at the International Space Station (ISS), crews aboard both the Soyuz and the station began working to seal the link between their vehicles, and opened the hatches at 6:57 a.m. EDT (1057 GMT). The new arrivals join current station commander Gennady Padalka, a cosmonaut, along with Belgian astronaut Frank De Winne, Canadian Space Agency astronaut Robert Thirsk, Russian cosmonaut Roman Romanenko, and NASA astronauts Nicole Stott and Michael Barratt.

"Everything was wonderful, we made it here all right," Suraev, the Soyuz commander radioed down upon entering the station. "The crew has pretty much adapted already. I can't even report any issues at all."

The three new arrivals greeted the station crew with hugs and smiles, and then got to say hello to family and officials gathered on the ground at Russia?s Mission Control Center near Moscow.

"We had a great trip up here and we're happy to be onboard in good company," Williams said.

Laliberte said he felt "pretty good" for his first time in space, and Suraev gave him a glowing review, saying, "He did great. His tolerance for weightlessness was absolutely perfect. Five on a scale from one to five."

The Soyuz-TMA-16's arrival also marks a first:

"This is the first time in history when we have three Soyuzes docked to the station at one time," Padalka said.

Mission for water

Laliberte is devoting his space journey to campaigning for water conservation issues. He founded the non-profit ONE DROP foundation to advocate for the cause, and plans a massive space performance for Oct. 9 to spread the word about the importance of global access to clean water.

"When I founded ONE DROP, it was (or rather, it still is) desperately urgent to do something to protect water," Laliberte wrote before launch on his blog at OneDrop.org. "ONE DROP is already acting in practical terms, but in the project of going into space, I saw an innovative opportunity, reflecting the image of Cirque du Soleil and my own image, too."

The performance will feature Laliberte reading a poem from space, while artists and personalities in 14 cities around the world will contribute through a simultaneous webcast. People including Al Gore, Shakira, U2 and Peter Gabriel will participate in the event, the first artistic performance from space.

In addition to activism, Laliberte plans to have some fun clowning around in space as well - he has threatened to tickle his crewmates and play practical jokes while on the space station.

"Of course, it is thanks to my own financial situation that I have been able to experience such an adventure," he wrote. "And yes, I am also making a personal dream come true through this mission."

He is the seventh paying tourist to fly to space on trips booked by the U.S. firm Space Adventures.

"I'm very excited about this journey I'm undertaking and everyone I'm meeting through it," he wrote. "This is both a personal challenge, as everything I'm experiencing here is new to me, and a grand project that will benefit my ONE DROP Foundation as well as Cirque du Soleil."

Crowded station

The new space station Expedition 21 mission is set to begin Oct. 9 during a change-of-command ceremony that will install DeWinne as the new station commander. The mission is only the second station increment with a six-person crew, doubled from the previous crew complement of three.

The more crowded station is also an increasingly-large one: The orbiting laboratory is almost completely assembled and is about twice the size it was when Williams last visited in 2006 as an Expedition 13 flight engineer. But simply building the station does not end its mission, he said.

"When we complete it, we need to utilize it," Williams said in a preflight interview. "My hope is that we get the full utilization out of this magnificent technical accomplishment."

Williams is set to serve as a flight engineer on Expedition 21. Then in December he will take over as commander of the new Expedition 22. His crewmate Suraev is a rookie spaceflyer and will take up the post of flight engineer for both Expedition 21 and Expedition 22.

The new crewmembers are in for a busy mission full of scientific research and station maintenance. During their stay they will host two visiting space shuttle missions, one more Soyuz flight, and a handful of unmanned cargo craft arrivals. Among the new supplies and equipment to be delivered on these flights is a new node module named Tranquility, which will include a panoramic window called the Cupola.

The expedition will also include a spacewalk, or extravehicular activity (EVA) in NASA parlance, in which Suraev will take part.

"I do have just one EVA during my mission," he said in a preflight interview. "On the personal side, I'm really looking forward to the EVA. And as a professional, I really want to not make mistakes during my flight."

Guy Laliberte is chronicling his Poetic Social Mission using Twitter ("ONEDROPdotorg"), Facebook and the Web site: OneDrop.org.

SPACE.com is providing full coverage of the launch of Laliberte and the Expedition 21 crew with Staff Writer Clara Moskowitz in New York. Click here for mission updates and live mission coverage.

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