For a special Space issue of Maclean’s—on digital and physical newsstands now—we spoke with nine Canadian astronauts, seven of whom have been in space. Here are excerpts from those annotated conversations about Mars One, a controversial project that promises to establish the first human settlement on Mars by 2025. Do astronauts think it can be a reality, or even the right move? You can read all of our interviews with nine Canadian astronauts, annotated with interesting bonus space facts, here.

Q: What do you think about the individuals signing up for Mars One?

Julie Payette: That project is a fraud. They’re not going to put anybody on Mars. They don’t even have a vehicle. Personally, I look at it as a marketing ploy, and a very effective one. They have no vehicle, no spaceship, no real plans to build anything and certainly no test program. It takes years to put out a new airplane. Look at the Bombardier C-series. How many years have we been testing this aircraft? And it’s not yet available. And you think that some company [that] specializes in reality TV can then build a unique spaceship to go for the first time ever, in the history of mankind, to another planet? Now, will we go explore? Absolutely. That’s what humans have been doing since we left the caves in Ethiopia. Why? Because this is part of our nature. We’re curious. We want to push the envelope. That will never stop. We will see people on Mars, hopefully in our lifetime. My hope is that the endeavour is so large, so complex, so technically challenging, so demanding and so uplifting, that it will be done with a consortium of nations. I hope the people who do set foot on Mars will do so for all mankind, and not just one nation in particular.

Jeremy Hansen: I don’t think they’re crazy to want to go. I think there are people in different phases of their lives, and I think there are people who’d be happy to go and do that. I have a wife and three children and, for me, there has to be a return. I can’t just check out of all these things that I’ve committed to here on Earth.

I think my career will end too early for me to go to Mars, though I might be involved in preparing the next generation to go. I’d love to explore Mars, but, ultimately, it’s kind of a crappy planet. The thing is, [Mars One people would] never go outside without a spacesuit ever again. You’re going to live in a tin can. Space stations are noisy; it’s like living inside a computer with the fan on all the time. You’re never going to smell grass or trees. It’s just never going to be anything like Earth. You’re never going to swim. You’re giving up so much.

Q: Would you ever take a one-way trip to Mars?

Robert Thirsk: I think the people who have volunteered for that are brave and visionary, and I want to encourage them in their training, but we don’t have the robustness and the reliability of technology, and, particularly, the life-support technology to provide for their survival. I was surprised by how much time I had to devote to repairing equipment for the space station. There were a significant number of critical space station systems that failed, that myself and my crew mates had to rally around and work with the ground to repair. A classic example was the oxygen-generation assembly. It’s kind of important. That failed. So we had to repair that. Another one was the carbon-dioxide-removal assembly. And that’s also important, because every time you breathe, you put more carbon dioxide into the room. Here on Earth, you just open up the door or turn on the air conditioner to take care of that. You can’t do that in space. That failed, and we were in a crisis. We had to quickly repair that. It’s going to sound funny to you, but the toilet failed as well. If the toilet’s not working, it’s really uncomfortable. So when people talk about a one-way trip to Mars within 10 years, I think that’s fantasy.

Roberta Bondar: As a physician and a person who has been doing so much space research, I think it’s unethical, absolutely. Some of the mouse models that have been exposed to the background radiation of space have evidence of Alzheimer’s disease. There is so much we don’t know. People are so cavalier. People say, ‘Oh yes, we can conquer space.’ People just aren’t realists.

Q: Should we be going to Mars?

Chris Hadfield: The U.S. has decided that its long-term goal for human space flight is Mars. It has water, heat, an atmosphere, 38 per cent of Earth’s gravity, deep caves, ice caps and the allure of hidden life. It’s also the prime choice in pop culture, with movies such as The Martian, as well as populist ideas like Mars One. But there is much to invent before we will ever actually go to the red planet. The myriad problems of primitive, slow rockets, interplanetary-radiation exposure, communication-lag effects, thin-atmosphere landing systems, reliable food production, and closed-loop water and waste recycling all need to be solved before we turn tail to Earth and head for Mars. Those technologies will need to be tested and proven in a place where we have the option of returning home when we inevitably make mistakes. And, after the Space Station is done, that place will be the Moon.

Q: What are you most excited to see in the coming years as space science and space technology advance?

Marc Garneau: I would love to see the world’s space programs continue toward sending humans to an asteroid or to Mars, with, of course, a full plan in place to bring them back. That excites me. And one of the things that excites me most about space is that we can go up there and put spacecraft in orbit with sensors that will help us measure the health of our planet, which is becoming particularly important. Our planet needs to be observed.

Get to know the great unknowable. Read Maclean’s special Space issue, on newsstands this week and on Next Issue, Apple Newsstand and Google Play now.

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