The most frustrating thing about being in space, according to Chris Hadfield, is sleeping.

Speaking to reporters from the International Space Station on Monday, the Canadian astronaut said he would rather make the most of his time in orbit — whether by running experiments or just looking out the window as Earth spins below him.

"The only thing that gets me mad is I have to sleep," said the 53-year-old astronaut, who earlier this month became the first Canadian to command the ISS.

"This is a tremendous opportunity … and my resolution has been to make the absolute most of it," he said while floating amid the many instruments that line the walls of the space station. "When I get back from this, I will regret every minute that I didn't spend looking at the world, or trying small experiments, or doing things that are impossible in the rest of my life."

Those experiments include research into anti-matter, crystallization and the first field-testing of the Canadian-made medical device "Microflow."

The device, a white box about the size of a loaf of bread, spun lazily in the air to Hadfield’s right as he explained its advances in blood analysis.

"When you challenge people with a new extreme, with a new frontier and a new environment, they come up with new solutions," he said.

Hadfield has been in orbit since December but has stayed close to home nonetheless — sending down tweets and photos of Earth, including snaps of Ireland taken on Sunday in honour of St. Patrick's Day. In January, he spoke via video link with students of an Ontario elementary school about his high-flying job.

Being in space gives one a new perspective on Earth and its problems, he added, describing the view from the station’s "big window."

The Earth looks both magnificent and fragile from space, said Hadfield.

"When you see the blackness and the harshness of the universe — and the one layer of onion-skin atmosphere that's around our planet — it becomes so vivid in your mind that it permanently changes your thinking," he said.