A nine-year-old Chris Hadfield is glued to the television screen at his neighbour’s cottage. It’s 1969 and the first moon landing is being broadcast around the world. As he witnesses the first astronauts walk on the moon he thinks to himself, “Wow, is that possible?”

Hadfield, 57, included this treasured memory in his new children’s book The Darkest Dark because he wanted to share how he conquered his fears and turned his dream of becoming an astronaut into a reality. Hadfield told CTV’s Your Morning on Friday that he wrote the book to show kids what is possible in life.

“It’s okay to be afraid,” he said. “But what you do and what you dream of and what you turn yourself into, that’s what really matters.”

The Darkest Dark is the retired astronaut’s third book and first children’s book. It focuses on the theme of children being afraid of the dark and how to overcome those fears. Hadfield admitted with a laugh that he, too, was once afraid of the dark as a child and that he thinks it’s normal. He also stressed the importance of recognizing and acting on fears at any age.

“If you can see past the fear,” he told CTV News Channel. “If you can see how your own actions can take you through the fear to get to something that you just dream about, it’s really my own past, but hopefully it’s useful to kids all around the world.”

Hadfield described how watching the moon landing in 1969 gave him the long-term goal of becoming an astronaut before Canada even had astronauts. He said he thought about how he could change himself so that when Canada did have a space program they would pick him. Hadfield’s dreams came true when he flew his first space flight in 1995 and became the first Canadian astronaut to walk in space in 2001. He has flown to space a total of three times and was also the first Canadian commander of the International Space Station in 2013.

“That’s the whole essence of life to me,” Hadfield said. “It’s trying to expand your horizons, learn about it and then decide what to do.”

Even though he is now a retired astronaut, Hadfield hasn’t stopped expanding horizons here on earth. He just returned home from an 18-day expedition to the Arctic on Thursday where he led a team of 10 creative, young artists on a mission to showcase that part of the world.

“What I wanted to do was let people see the Arctic with no filter,” he said.

The astronaut-turned-author said his favourite moment from the journey was when his whole team walked to the edges of a glacier they were exploring.

“They stand and face different directions and just let the enormity and the age and the beauty and the life of that place soak into them and change who they are,” he said.

As for how his latest book is being received, the proud grandfather said he shared his book with his new granddaughter, Eleanor, who is still at the “little fat-fingered-turning-the-pages kind of level” so he might have to wait until she’s a little older for her review.

The Darkest Dark will be released Sept. 13 in six languages.