Space is getting busier as national space agencies and personal firms increase the tempo of launches. But today’s approach to space exploration is unsustainable, say researchers, and we want to do more to ensure the orbital economy is a circular one.
While firms like SpaceX have made progress with reusable rockets, most launch vehicles are used just once, and their stays are left to either burn up within the atmosphere or clutter low-Earth orbit. In addition they 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.
Because the pace of launches grows, these approaches aren’t any longer viable, say researchers. In a paper published in Chem Circularity, scientists argue we want to shift to a “circular space economy” designed across the principles of reducing, repairing, and recycling.
“As space activity accelerates, from mega-constellations of satellites to future lunar and Mars missions, we must ensure exploration doesn’t repeat the mistakes made on Earth,” the University of Surrey’s Jin Xuan says in a press release. “A really 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 cut back waste within the industry, they are saying spacecraft have to be more durable to extend their lifespans. This might slash material waste from the vehicles themselves and reduce the variety of launches required.
Making spacecraft more repairable could also play a very important role, they note. To make this possible, space stations would wish to grow to be hubs that perform maintenance and construct spacecraft components. They may also refuel satellites already in orbit to increase their lifespans.
Recycling spacecraft is tougher resulting from the large amount of wear and tear and tear they undergo in the cruel conditions of space and the punishing means of re-entering the atmosphere. The researchers say firms have to further develop soft-landing systems like parachutes and airbags to make sure vehicles may be brought back safely.
The study also calls for systematic efforts to clear existing orbital debris. These would cut back the chance of collisions but could also get better precious materials. The work would require latest tools like robotic arms and nets that may safely capture spacecraft moving at 1000’s of miles per hour.
The largest challenge, the researchers say, is this may represent a fundamental shift in the way in which the space industry operates. Which means piecemeal progress on individual components or processes won’t cut it: What’s needed is a system-wide commitment to radically alternative ways of operating.
“We want innovation at every level, from materials that may be reused or recycled in orbit and modular spacecraft that may be upgraded as an alternative of discarded, to data systems that track how hardware ages in space,” says Xuan. “But just as importantly, we want international collaboration and policy frameworks to encourage reuse and recovery beyond Earth.”
Which will prove difficult in an arena that has been characterised by intense geopolitical competition. But we now have a golden opportunity to avoid the identical mistakes we now have made here on Earth.