The special commission will decide whether the men are ready to go into space. However, many at Star City believe this final exam is a pure formality, since the crew members have already gone through years of tough training, and failing the exam is almost impossible.

During the exam, the future cosmonauts have to demonstrate how well they understand each other, work together and deal with emergency situations. After getting their tasks, the cosmonauts will have to fulfill them. Their performance will be evaluated on a five-point marking scale.

To pass their tests the cosmonauts will use two full-scale mockups – one of a Soyuz spacecraft and another of a Russian part of the ISS.

“We can’t re-create [zero] gravity here. We can’t create [a] vacuum here either. We train how to perform in the depressurized situation,” said Sergey Krikalyov, head of the cosmonaut training center. “I think dealing with depressurized situation is as dealing with fire. We also can stimulate fire, of course, without creating it.”

Maxim Surayev (L), Guy Laliberté (C) and Jeffrey Williams (AFP Photo / Dmitry Kostyukov)

His American counterpart, Jeffrey Williams, is more experienced: he previously resided on the ISS for six months in 2006 as a member of the Expedition 13 crew.

The commander is optimistic.

“I feel great,” Maksim Surayev said. “Me and Jeff have been through a lot as a crew. Also, I've been training for a long time, and the guys up at the station are all well prepared, too.”

Spacemen are known for being superstitious but they say the omens for this trip are good.

Canadian billionaire, 50-year-old Guy Laliberté is the founder of the Cirque du Soleil entertainment company. He will spend 12 days on the ISS.

“Actually when I arrived here, I was in my worst shape ever, so I had to get back in shape. I am far away from my acrobatic time of my 20 years, when I was 20,” he said.

“The most exciting thing is I think the entire experience from the training. And I can’t wait to experience the flight. The most difficult for me was [the] rotating chair,” Guy Laliberté said.

Meanwhile, the thirteen astronauts aboard the ISS are finishing their space mission with a farewell party. The crew members are packing their bags, exchanging presents and mobile phone numbers.

They have spent 100 days in space, watched at least 1,600 sunsets and traveled 70 million kilometers.

Now all they have to do is learn how to walk again.

The shuttle is expected to return to Earth on Thursday, but there's one last job to be done before they go: tidying up. Over a ton of rubbish amassed during their stay will be transported and recycled on Earth.

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