'If we can make a space station fly, we can save the planet': An astronaut's view on protecting the Earth

French astronaut Thomas Pesquet spent six months aboard the International Space Station last year, and his view of the Earth was as alarming as it was breathtaking.

Long periods with his feet off solid ground gave him a unique and privileged perspective on our planet. His Instagram account is bursting with beautiful images of “the blue ball we call home.” But the beauty is tainted. Pesquet says that even from space the effects of climate change are visible.

He says that since his previous visit to space, in 2016, the consequences of human activity have become even more apparent, with glaciers visibly retreating, and a rise in extreme weather events.

Environmental concern motivated him to become a UN Food and Agricultural Organization (FAO) Goodwill Ambassador. As an astronaut on board the ISS he supported the FAO’s research into agricultural innovation and methods of food production. Limited resources in space provide an opportunity to model human behavior on a planet with dwindling resources, and Pesquet wants to highlight the parallels between life on a spacecraft and life on Earth.

CNN spoke to Pesquet at the Houston Museum of Natural Science. This interview has been edited for clarity and brevity.

CNN: What does the Earth look like from “out there?”

Pesquet: When you look at the Earth from the space station, it’s absolutely magical. You’re not that far away, so you still have a relatively close-up view. But you can see the curvature and you see the atmosphere. It glows in blue. It is absolutely breathtaking the first time you see it. It’s the most beautiful scenery you could possibly imagine.

When you’re on the Earth, you feel that everything is so vast, everything is endless. You have a hard time understanding how limited we are. Then, when you take a step back and you see the Earth in its entirety, you suddenly understand that we live in an oasis in the cosmos. All around us is nothing, no life, blackness, emptiness, absolutely nothing – apart from this blue ball with everything we need to sustain human life, and life in general, which is absolutely fragile.

It makes you want to cherish the Earth and protect it, the more you see it from space.

CNN: What are the real effects of climate change that are visible from space?

Pesquet: You can see a lot of the consequences of human activities from space. Some of them are from climate change, and some of it is just plain old pollution, e.g. river pollution, air pollution.

The most visual visible effect is glaciers retreating year after year and mission after mission.

But what you can see as well is extreme weather phenomena. They’re getting stronger and stronger year after year. My first mission was 2016-2017, and my second mission was five years later in 2021. I could see a net increase in the frequency and the strength of extreme weather phenomena like hurricanes, like wildfires.

Read: Explorer’s mission to photograph a century of climate change in Patagonia

CNN: What contribution can an astronaut make?

Pesquet: There’s a ton that you can do from space to help out on the planet. First of all, as a space agency, we have satellites that can observe the Earth and measure variables such as the heights of waves, the temperature of the sea, ice on the polar caps retreating.

But we can also go a little bit deeper. We have experiments that are geared towards protecting the planet – for example, experiments on fluids. Fluids in orbit behave differently, so our research is trying to understand the motion of the magma and lava inside the planet, and the movement of waves in the ocean. This can help us predict some of the extreme weather events that affect our environment.

Crucially, we have to manage our limited resources onboard the space station. We have limited atmosphere, limited water, limited food. And so the way we deal with everything on board the space station gives us techniques that we can apply on Earth because the situation is parallel. I think the people on Earth can learn a great deal about how space technology deals with water, how we recycle water, how we recycle air oxygen.

CNN: Does it take its toll on family life when you’re away in space for several months?

Pesquet: It’s not easy for us being up there, and it’s not easy for the people we leave behind. The toughest thing is being deprived of your loved ones, and also being constantly worried that if something happens to them, you cannot help them. I think it’s the nightmare of all the astronauts, that something happens to their families on Earth while they’re away.

Read: James Cameron’s plea to protect the ocean twilight zone

I believe there’s an element of selfishness in me going to space because it’s a fantastic magical experience. But I also firmly believe that there’s a hugely positive impact on society in general because of what we do; because of the research, because of the international cooperation. So I think we have to do it even if there’s a price to pay. It’s not easy, but I think it’s a good thing to do.

CNN: As a climate advocate, do you think about the environmental cost of space travel?

Pesquet: As an astronaut, you witness the fragility of planet Earth, while simultaneously thinking, “wait a minute, what is my impact on all this? I’m going to space in a rocket, how does that impact the environment?”

Yes, space travel produces some CO2, and it is not entirely environmentally friendly. But I think you have to take into account the positives with the negatives. There are so few rocket launches that compared to aviation, cars or other industries, our impact is negligible. We need activity in space to get satellite research done. This benefits the planet a lot. So space travel is a necessary evil.

CNN: Since you have returned from the ISS, what are your hopes for the future protection of our planet?

Pesquet: If we set ourselves on the right path, there’s nothing we cannot do. We built this unbelievable facility in space for good reasons. We’re using it every day, in peaceful cooperation between countries that were not always friends. So if we can transfer that model to the way we deal with the environment on Earth, I think we’ll get there.

We’re creative enough, we have the technology and we have the will. So I’m optimistic for the future. If we can make a space station fly, then we can save the planet.

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