Chris Hadfield on exploring Mars and the growing conversation about UFOs

Landing a rover on Mars is "almost indescribably difficult," according to retired Canadian astronaut Chris Hadfield.

Despite that reality, scientists have landed a handful of them on the Red Planet.

China's space agency is the latest to do so, dropping the Zhurong rover on Mars earlier this month. On Saturday, it took its first drive on the planet's surface .

Hadfield, who was the first Canadian commander of the International Space Station, said conducting research on Mars is crucial to finding out whether we're alone in the universe.

"Why are we trying to land on Mars? Well, I think the fundamental question is that Mars was a lot like Earth four billion years ago when life first formed on Earth," he told Cross Country Checkup guest host Jason D'Souza on Sunday.

"So if it happened here, did it happen there? And it will be evident somewhere in the geologic record."

The rovers currently traversing Mars are conducting research and taking samples from the ground. If a rover finds one fossil, Hadfield said, "we will know we're not alone in the universe."

Hadfield joined Checkup as part of the program's regular Ask Me Anything series, and answered questions from listeners about Mars, unidentified flying objects and our responsibility as humans in space.

China's Mars probe beams 1st images from the surface of the Red Planet World 0:42 Watch video captured by Tianwen-1 lander and photos from the Zhurong rover. 0:42

With rovers — and possibly one day humans — landing on Mars, Ed Camelot in Edmonton asked "what's in it" for the Red Planet?

If there is life on Mars, whether fossilized or primitive, Hadfield said it's important to consider what it would mean for us on Earth, and what responsibilities we have.

The 1967 United Nations Outer Space Treaty offers "fundamental building blocks of the legal system" for space-faring nations, he said.

That treaty is a basic framework on international space law, according to the UN, and outlines key principles, including that space exploration should be in the interest of all countries, and that states should avoid harmful contamination of outer space and celestial bodies.

"We're very careful with everything we've sent so far to Mars to make it — to the absolute best of our ability — to make it sterile so that it won't inadvertently bring life to Mars or react if there is some sort of primitive life on Mars," Hadfield said.

"If there was intelligent life or advanced life, we would treat it even more thoughtfully and more differently."

Asked whether he would ever consider a "one-way trip" to Mars, Hadfield said he has spent his entire life taking great risks for space exploration — but astronauts don't make big journeys without proper preparation.

With that in mind, he told Checkup he would happily help with development of technology to enable Earthlings to live somewhere hostile, like Mars or the moon.

"I'm interested in it, but my question would be what ship and who with and what is the purpose?" Hadfield said.

"We're going to get there eventually, and I'd love to be part of the team that makes that happen."

A portion of a panorama made up of individual images taken by the Navigation Cameras, or Navcams, aboard NASA's Perseverance Mars rover shows the Martian landscape on Feb. 20, 2021. (NASA/JPL-Caltech/Reuters)

Calling from Kamloops, B.C., Byron McDonald asked whether Hadfield is following the growing discussion about unidentified flying objects.

Often a taboo subject, the presence of UFOs has become a hot topic not only on social media, but in mainstream media and even the corridors of power in Washington, D.C.

The news magazine 60 Minutes recently aired a report about UFO sightings in U.S. airspace. Next month, a report on what the U.S. government calls unidentified aerial phenomena, or UAPs, will be delivered to Congress by U.S. intelligence agencies.

"Obviously, I've seen countless things in the sky that I don't understand," said Hadfield, a former pilot for the Royal Canadian Air Force and U.S. navy.

"But to see something in the sky that you don't understand and then to immediately conclude that it's intelligent life from another solar system is the height of foolishness and lack of logic."

Hadfield acknowledged the existence of extraterrestrial life is worth thinking about, and that it's likely that there is life in other parts of the universe.

"But definitively up to this point, we have found no evidence of life anywhere except Earth, and we're looking," he said.

Still, Hadfield said it's not surprising that the conversation is gaining steam.

"It's intriguing and it's right on the brink between reality and science fiction and fantasy. And so it's all really fun to think about."

Written by Jason Vermes. Ask Me Anything with Chris Hadfield produced by Steve Howard.

Hear the full conversation on CBC Listen, our free audio streaming service.