MONTREAL -- Canadian astronaut David Saint-Jacques says the biggest part of his preparation as he gets ready to leave Dec. 20 for a visit to the International Space Station is making sure his family is OK.

He held a news conference this afternoon at the Johnson Space Center in Houston to discuss his first trip into space.

Saint-Jacques was joined by U.S. astronaut Anne McClain and Russia's Oleg Kononenko, who will both be with him when they blast off from Kazakhstan aboard a Russian Soyuz space capsule.

He says he wants to make sure everything in his life is in order before he leaves to spend six months in what he calls a " very far place."

The 48-year-old astronaut is the father of three children -- boys aged seven and five and a two-year-old girl.

Saint-Jacques adds his space colleagues are also thinking of their families with just more than three months left before they leave the planet.

He also says he's now entering a different phase of his training, which involves learning about the science experiments that will be carried out aboard the space station.