Astronaut David Saint-Jacques part of backup crew in advance of his own liftoff

Canada's next man in space doesn't have his official liftoff date until the end of this year, but David Saint-Jacques says he's ready if called into action in the coming weeks.

Saint-Jacques is serving as a backup to European Space Agency astronaut Alexander Gerst, who is part of a three-person team scheduled to launch from Kazhakstan on June 6.

A backup crew being pressed into duty on short notice has never happened.

Saint-Jacques tells The Canadian Press he is relishing his future stay aboard the International Space Station after several years of training.

"For the last almost decade, I've been training in an adult version of space camp, it's been PowerPoint and simulators and trainers," he said from Kazhakstan.

"Now this is the real deal, and although I've been in the space program for a while, it's the first time I go through the real deal: all the real preparation, the real spacecraft, the real spacesuit."

The ninth Canadian to travel to space will serve as a co-pilot for the Soyuz capsule and crew medical officer on board the station. He will also be the "guinea pig" in numerous medically-related experiments sponsored by Canada during his six-month stay.

An astronaut since 2009, Saint-Jacques was named to the mission in 2016 and said it's mentally good to go through the motions before the real day.

For the next two weeks, he'll be on standby with his fellow teammates Russian Oleg Kononenko and American Anne McClain.

"If someone breaks their ankle or catches a bad disease a day or two before launch, there's a non-zero chance I might go," Saint-Jacques said. "This has never happened, not on short notice."

The engineer and doctor will be the first Canadian to visit the station since Chris Hadfield spent five months there in 2012 and 2013.

Saint-Jacques is scheduled to launch aboard a Russian Soyuz spacecraft on Dec. 20 at the Baikonur Cosmodrome in Kazakhstan and remain on the station until June 2019.