The transfer of command to space veteran Chris Hadfield will be marked Wednesday by the simple ringing of a ceremonial bell.
He is almost three months into his five-month space visit.
Since his arrival on Dec. 21, 2012, the Canadian space veteran has been taking spectacular photos of the world beneath him and posting them on Twitter. Hadfield's colourful, detailed images have received international attention and helped him gain over 500,000 Twitter followers.
Another recent photo showed an apple with Velcro on the bottom which, Hadfield explained, allowed him to set it down between bites.
But the 53-year-old spaceman may have to cut down on the amount of time he has devoted to his nascent photography career.
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The transfer of command to Hadfield, and the start of what's officially designated "Expedition 35," will happen at 5:10 p.m. ET.
Hadfield takes over the top job in outer space from NASA astronaut Kevin Ford, the station's 34th commander.
Former Canadian astronaut Bob Thirsk is confident his old colleague will do a good job. Thirsk spent six months on the station in 2009 — a record stay for a Canadian. One of Canada's first six original astronauts, he retired in August 2012.
"Chris Hadfield is an astronaut's astronaut," Thirsk told The Canadian Press in a recent interview. "He's got all the skills, the knowledge and the personality to excel as commander."
In past interviews, Hadfield has said that it was "a tremendous honour" to be entrusted with the lives of other astronauts and the space station.
Thirsk also pointed out that Canada is the smallest partner among the five agencies involved in the space station program.
"It makes a remarkable statement about the nature of this partnership when the smallest country has the opportunity to assume one of the more critical roles," he said.
Aside from Hadfield, the only other space station commander who wasn't either American or Russian was Frank De Winne of Belgium, who was in charge while Thirsk was spacebound. De Winne is a member of the European Space Agency.
Thirsk credited De Winne with creating a harmonious atmosphere.
He said Hadfield, a native of Sarnia, Ont., has to be ready for anything.
"In the event of an emergency when the station might lose communications with mission control on the ground, it'll be Chris who must take directive action and keep the crew and the station safe," he added.
As recently as Feb. 19, there was a temporary loss of communication between the space station and the ground, which lasted for several hours.
Recalling his own experience, Thirsk had some advice for Hadfield during his stint as station commander: "Keep 'em laughing."
"Once a week, we would have these conferences with the main managers of the ground support team and we would spend half of the time just laughing," he said.
"You know things are going well when that happens."
Hadfield is on his third space mission.
His first trip was an eight-day mission in November 1995, when he visited the Russian Space Station Mir. His second was a visit to the International Space Station in April 2001, when he performed two space walks during an 11-day voyage.