There’s an international element to the debate, too, as the FCC’s rule could apply to some satellite operators beyond the US. “The FCC is trying to design this so that it’s not only applicable to US license-seekers, but anybody who wants to access the US market. They’re trying to flex their muscles in a way that creates a rule that applies to other space operators,” says Bruce McClintock, head of the Space Enterprise Initiative of the Rand Corporation, a nonprofit research organization in Santa Monica, California. And others pay attention to US guidelines: For example, the United Nations Committee on the Peaceful Use of Outer Space adopted the 25-year rule in 2010, and it became the international standard. But the lack of coordination within the US government right now on the proposed five-year rule could limit its potential effectiveness, McClintock says.

Like ubiquitous plastic waste in oceans, orbiting junk has been building up for decades, and tens of thousands of pieces of trackable debris now hurtle through low Earth orbit at an altitude of 1,200 miles or lower, along with millions of bits too small to be tracked but not too small to damage a satellite. That means massive networks like OneWeb or SpaceX’s Starlink could be victims of debris impacts, even if the companies make an effort to promptly deorbit their own satellites.

McKnight argues that satisfying the five-year rule is worthwhile, because pushing defunct satellites to an altitude below 250 miles would limit risks to the International Space Station, China’s Tiangong ​​space station, and other crucial spacecraft. And he thinks that technological advancements, like a shift from chemical to electrical propulsion, will make it possible to move a satellite even if only 1 percent of the launch payload’s mass is fuel.

Other innovations might help too, says Marlon Sorge, aerospace technical fellow at the Aerospace Corporation, a federally-funded research and development center in El Segundo, California. “Adding propulsion for small satellites is pretty difficult, but there are other options, like drag-enhancement devices. These are things that deploy a long tether or a sail that increases its area,” he says.

Importantly, the FCC’s rule also will apply to upper-stage rocket bodies. Many of the old-timers in orbit were left behind decades ago by the US, China, and Russia. But since rockets can be too big to burn up upon reentry, they need to be brought back to Earth in a controlled manner, to an unpopulated patch of ocean.

McClintock points out that the biggest problem isn’t how much time owners have to deorbit their spacecraft—it’s that there’s no enforcement mechanism ensuring that they follow through on their plans. “An argument against a five-year rule, people will say, is that it’s a bigger concern that people are not yet complying with the 25-year rule,” he says. “If we had a higher compliance with the 25-year rule, we wouldn’t need a five-year rule.”

Still, when it comes to these controversial license requirements, it’s better to be safe than sorry, McKnight argues: “The space environment is not as forgiving as in air, maritime, and land environments. You don’t have aviation accidents affecting the next flight. In space, when the accident occurs, it’s lingering for decades or centuries.”