Space is getting busier as national space agencies and private companies increase the tempo of launches. But today’s approach to space exploration is unsustainable, say researchers, and we need to do more to make sure the orbital economy is a circular one.
While companies like SpaceX have made progress with reusable rockets, most launch vehicles are used only once, and their remains are left to either burn up in the atmosphere or clutter low-Earth orbit. They also dump huge quantities of greenhouse gases and ozone-depleting chemicals into the upper atmosphere.
Satellites are similarly unsustainable. After completing missions, they’re often either moved to a “graveyard orbit,” or worse, they add to the growing pile of space junk making low-Earth orbit increasingly hard to navigate.
As the pace of launches grows, these approaches are no longer viable, say researchers. In a paper published in Chem Circularity, scientists argue we need to shift to a “circular space economy” designed around the principles of reducing, repairing, and recycling.
“As space activity accelerates, from mega-constellations of satellites to future lunar and Mars missions, we must make sure exploration doesn’t repeat the mistakes made on Earth,” the University of Surrey’s Jin Xuan says in a press release. “A truly sustainable space future starts with technologies, materials, and systems working together.”
Progress already made in shifting industries like electronics and automotive manufacturing to more circular practices could provide a template for the space economy, say the researchers.
To reduce waste in the industry, they say spacecraft need to be more durable to increase their lifespans. This could slash material waste from the vehicles themselves and reduce the number of launches required.
Making spacecraft more repairable could also play an important role, they note. To make this possible, space stations would need to become hubs that carry out maintenance and build spacecraft components. They could also refuel satellites already in orbit to extend their lifespans.
Recycling spacecraft is more challenging due to the enormous amount of wear and tear they undergo in the harsh conditions of space and the punishing process of re-entering the atmosphere. The researchers say companies need to further develop soft-landing systems like parachutes and airbags to ensure vehicles can be brought back safely.
The study also calls for systematic efforts to clear existing orbital debris. These would reduce the risk of collisions but could also recover valuable materials. The work would require new tools like robotic arms and nets that can safely capture spacecraft moving at thousands of miles per hour.
The biggest challenge, the researchers say, is this would represent a fundamental shift in the way the space industry operates. That means piecemeal progress on individual components or processes won’t cut it: What’s needed is a system-wide commitment to radically different ways of operating.
“We need innovation at every level, from materials that can be reused or recycled in orbit and modular spacecraft that can be upgraded instead of discarded, to data systems that track how hardware ages in space,” says Xuan. “But just as importantly, we need international collaboration and policy frameworks to encourage reuse and recovery beyond Earth.”
That may prove challenging in an arena that has been characterized by intense geopolitical competition. But we have a golden opportunity to avoid the same mistakes we have made here on Earth.
