According to recent estimates by the European Space Agency (ESA), more than one million pieces of debris more than one centimeter long, from spent satellites or rocket bits, orbit the Earth at very high speeds. And that number is likely to increase dramatically with the advent of “mega-constellations” of satellites aimed at providing faster, ubiquitous Internet access.
Rules of good practice exist for limiting space debris. But this is not enough
“We are entering an era where many satellites will be launched one after the other. The space is going to get more crowded.”recalls Miki Ito, a director at Astroscale, a young Japanese company working on a space “sustainable”. “Simulations suggest that if we continue like this, space will become unusable.”, warns Mrs. Ito. “So we need to improve our heavenly environment before it’s too late. »
An experimental laser beam
Incidents are already escalating: In January, a Chinese satellite was grazed by fragments of an old Soviet satellite. And last year, the thermal coating of a robotic arm on the International Space Station (ISS) was punctured by debris just a few millimeters across. “Small debris is problematic because it’s not listed.”Unlike massive objects that have names and have positions and motions “Permanently identified”Japanese space agency JAXA researcher Toru Yamamoto explained.
Rules of good practice exist to limit space debris, such as, for example, diverting end-of-life satellites to a “Graveyard Orbit”. But this is not enough, especially since no legally binding international text currently exists.
There is no universal cure
According to this engineer, companies from all over the world are also lining up to conquer this nascent market, which could really take off from 2030 onwards. In late 2020, ESA signed a 100 million euro contract with ClearSpace, a Swiss start-up, to launch, in 2025, the world’s first commercial mission to clean up space debris in orbit.
American companies such as Orbit Fab and SpaceLogistics (a subsidiary of aeronautics and defense group Northrop Grumman), or Australian Newman Space design various satellite repair services to prolong their use, for example by refueling them in space. According to Jaxer Yamamoto, the space debris problem is sufficiently complex to allow a wide range of solutions to coexist. “There is no universal cure. »
“A geostationary satellite experiences about 100 ‘debris on approach’ warnings per year”, said Tadanori Fukushima, engineer at Japanese satellite operator Sky Perfect JSAT. Mr. Fukushima founded a start-up to dig up a still-experimental solution: a laser beam that would vaporize the surface of space junk, creating a pulse of energy to propel those objects into a new orbit. He hopes to launch the first experiment in space by spring 2025 in collaboration with various research institutes.
AstroScale’s idea is even more advanced: a kind of space “tow truck” works with magnets to retrieve end-of-life satellites. The company succeeded in the first test last year and plans a second one by the end of 2024 in partnership with ESA and OneWeb, the British operator of a constellation of low-orbit satellites. Japan is one of the most dynamic space nations in developing space debris solutions, Fukushima said.