Tognini spent a total of 19 days in space on two space flights after joining the French space programme in the 1980s following a career within the country’s air force. The veteran astronaut served as the head of the European Space Agency’s astronaut centre from 2005 to 2011.
I’m sure you get asked this all the time, but what is it like going to space and how did it change your perspective on Earth?
The mission is a long process of training. It's a complicated experience in terms of safety. You need to be prepared for any kind of failure. When you know the system, you feel better. And because you feel better, when you are out there, you will appreciate it more--enjoy the zero G feeling, looking at the whole Earth. You see places that you would never see in life.
It's very interesting to discover the beauty and the fragility of Earth. All astronauts come back saying we must do everything to protect Earth. There’s a very strong human link.
The mission of Asteroid Day is to protect Earth from a potential collision with an asteroid. How did you get involved?
When you're in space, you look at the atmosphere, you see this thin layer. And if this atmosphere disappears for any reason, we are dead. It’s not an impossible scenario, because this scenario happened on Mars. We’ve discussed environmental problems, the rising of temperatures, which is very important. But one of the scenarios could be the impact of an asteroid.
There is no protection from asteroids.
There is no protection from asteroids. But maybe in 20 years, we might have together founded the concept of a human mission to go an asteroid. Because we do more missions, we discover the context, the formation, what’s inside an asteroid.
Asteroids aren’t hard, like rock. They can be a soft material and because of that, the scenarios we had in the past of deflection with a nuclear explosion process has to be revisited. I’m more and more convinced that humankind can do something greater to protect Earth and avoid an asteroid impact. That’s why I’m here.
Last year, we got a satirical look at this scenario in the film Don’t Look Up. What did you make of it?
Scientists are living in their own world and politicians in a different world. This movie explained the lack of communication between the two and the lack of confidence. There is no trust. The movie is extreme, obviously. But even so, we have no protection system.
The next asteroid coming to us is Apophis in 2029. That’s seven years from now. We have to be very careful. Even if it is a small risk, we have to be prepared. And the way to prepare is a mission, similar to going to Mars. If you can go to Mars, you can go to an asteroid.
There are more concrete threats, like climate change, the war in Ukraine, the pandemic. What are the challenges to get attention for an issue that seems much more abstract and distant?
An asteroid is a catastrophic scenario. We have two hits every century. In the next 50 years, we should have one not so big one. Even so, the one that fell in Siberia seven years ago--around 20 metres long--if this falls on Paris or a big city, the city is destroyed. Even if the big ones haven’t been close so far, a small one could happen very quickly.
Asteroid mining has added a new dimension to this issue…
It's really important. There are two scenarios: if you go to an asteroid to bring back rare materials, the costs are very expensive. For five grams, it’s $1bn, I think. But if you go for exploration, it's good to know that there are places where there is energy. You could land on it and use this energy to go to a different place.
As we look for resources in space--or maybe even new habitats--how difficult will it be to maintain peace in space?
If you consider something like helium-3, there are about 500bn tonnes on the moon. This corresponds to over 10,000 years of energy. There’s a lot for everything. I don’t think it’s a real problem. Obviously the big ones will be the first to go there, like China or the US, but it will be shared.
When you are in space, the only beautiful place is Earth.
This is why we do the space station. It teaches us to work together, and this template can be used to go to the moon or Mars. We can be proud that humankind can cooperate in space.
At the same time, defence is playing an increasing role in space. The US has Space Force, there’s the EU’s strategic compass for defence. Even Luxembourg has a space-defence strategy. What are your points of contact with these developments?
We are not too much linked with space defence, because it has no link with human space missions. Space defence is about satellites to observe Earth or it could be encrypted radio transmission. The new thing that we saw is the interception of satellites. Countries want to show they are capable of doing it.
What role do you think can space defence strategies play to potentially deflect an asteroid?
It’s difficult to say. It’s not a concern of the military. But it’s important to come to this meeting every year, because one day, when an asteroid is coming--like in the movie, Don’t Look Up--if you’re not prepared, you cannot build a huge organisation to intersect it. We have to prepare years and years before. We keep this low-level organisation going--going to low-Earth orbit, to the moon and one day to Mars--so if one day we go to an asteroid, it’s the same: same distance, same problems.
The goal of humankind is to protect the Earth. I don’t agree with people who say that we transport all people from Earth to Mars. Earth is beautiful. When you are in space, the only beautiful place is Earth. All the rest looks so stark, grey and unfriendly. It will be difficult to find a second Earth, so we have to be careful of our environment.