Live the ecstasy of weightlessness, with a view of the Earth and without thinking about its future: space tourism still counts for negligible quantity in terms of pollution. But in this time of climate change, questions are emerging about the carbon footprint of this activity, which could take off quickly.
On July 11, British billionaire Richard Branson successfully flew for a few minutes to the frontier of space. Tuesday, it will be the turn of Jeff Bezos, the richest man in the world, to visit the great void with his Blue Origin capsule.
These private “suborbital” flights undoubtedly constitute a turning point in the advent of space tourism: Richard Branson’s company, Virgin Galactic, has already sold 600 tickets, between 200 and 250,000 dollars, and ultimately aims to conduct 400 flights per year. .
With what impact on the planet? Difficult to assess, as this hobby for the ultra-rich remains ultra-marginal, still far from the radar of environmental defenders.
But the problem will arise if this tourism becomes massive.
“If we wanted to send 50,000 tourists a year into space tomorrow, there would be a real environmental issue,” the CEO of Cnes (the French space agency), Philippe Baptiste, said on Friday on a French radio station.
A “quiver of critical discourse, stifled so far by the enthusiasm of the beginnings, begins to rise”, notes Arnaud Saint-Martin, a French sociologist of science.
“At a time of climate change, it is clearly not the time to launch an activity that will increase certain emissions”, adds Finnish researcher Annette Toivonen, author of “Sustainable space tourism”.
The American scientist Martin Ross, who compared the technologies of the two billionaires, showed that Jeff Bezos’ vehicle uses a mixture of hydrogen and oxygen, considered less polluting.
– CO2 and soot –
Richard Branson’s spaceship, on the other hand, appears to be particularly polluting, because its solid fuel propulsion technique produces CO2 (the main cause of climate change) and spits soot while crossing the stratosphere.
“It’s as if you were burning a tire” in an area of the atmosphere where the air, less dense, is recycled less quickly, notes Christophe Bonnal, of the CNES launchers department.
Asked by AFP, Virgin Galactic assured to be “engaged in a process aimed at reducing the impact on the environment, with a view to a sustainable development” of its activity. And indicates that the carbon footprint of one of its flights “was equivalent to that of an individual trip in business class aboard a flight London-New York” by plane.
The emissions remain indeed modest “if we compare them to the 915 million tonnes of CO2 emitted in 2019 by the 4.5 billion passengers on commercial flights”, noted several French scientists, on the site The Conversation in September 2020.
But Virgin Galactic’s suborbital sprees still represent “4.5 tonnes of CO2 per passenger”, or “twice the annual individual emission allowing, according to the IPCC (UN climate expert group, Editor’s note), to respect the objective of + 2 ° C of the Paris agreement “of 2015, according to these scientists.
Moral and political considerations are added to these ecological questions, which castigate “luxury rides” for the very rich in search of sensations.
“In a context of climate emergency and pandemic – where more sober development models are discussed, in particular the green plane -, one can wonder if these trips are not a superfluous need”, argues Arnaud Saint- Martin from CNRS.
– The Moon on the horizon –
At its beginnings too, aviation was perceived as a “sport for the rich”, notes Christophe Bonnal. With the difference that the first flights of Alberto Santos-Dumont or Louis Blériot “allowed the progress leading to today’s aeronautics”.
“But what shocks me in the flights of Richard Branson is that there is no horizon behind”, argues the expert. Jeff Bezos, him, “a priori plays on a field other than mass tourism: he sees big, he aims at the Moon, and further still with humanity leaving the planet”.
In the meantime, (rich) space fans concerned about their carbon footprint will be able to test “zero-emission” balloon trips, which the French company Zephalto will notably be offering from 2024.
At an altitude of 25 km, propelled by helium – a neutral gas – passengers will dive into the darkness of space to admire the curvature of the blue planet. “We hope the show will make you think, because what the astronauts are saying is that once you see the atmosphere so fine above the Earth, you become aware of its fragility,” said the director of the start-up, Vincent Farret d’Astiès.