The word sustainability has become somewhat synonymous with the environmental movement. But really, the word is about longevity. It asks us to ponder whether a particular action or system can be maintained indefinitely, or is in some way self-defeating, self-limiting, or self-sabotaging.

We know that on Earth, many of the behaviors underpinning modern society aren’t sustainable. Our insatiable hunger for growth is polluting the land, air, and seas, and jeopardizing access to those life-giving resources for future generations. But man’s destructive tendencies aren’t limited to Earth alone. As we rapidly expand our presence in space, unchecked growth threatens to make low-Earth orbit unsafe and inaccessible to the would-be explorers of tomorrow. And NASA is getting worried.

“In the last 10 years, the number of participants and new activities in space has changed,” says Charity Weeden, head of NASA’s Office of Technology, Policy, and Strategy. “It’s not just communication satellites. We have in-orbit services, transportation in space, commercial destinations for humans in the future. Couple that with the six-and-a-half decades of society using space without necessarily thinking, and there’s more uncertainty about what operators are doing in space and how we all interact with each other.”

In a move to protect space for the years to come, NASA recently released its new “Space Sustainability Strategy” and plans to hire a director of space sustainability whose job it will be to put the strategy into effect across the agency. That’s no small task: Nearly 18,000 people work within NASA, spread out across dozens of divisions and offices. The director of space sustainability will help make sure the entire agency is working to preserve space even as it becomes more crowded.

“The plan is for NASA to aggregate all our [sustainability] efforts across the agency,” Weeden explains. “We have disparate efforts across the agency and we haven’t put them all under one single understanding. That’s the intent of this strategy.”

But before that can happen, NASA has to identify the parameters. This exercise is much easier when considering sustainability on Earth. For example, we know humans need clean air to breathe and fresh water to drink, and anything that compromises these resources long term is decidedly unsustainable. But space is an unnatural environment that humans aren’t really supposed to inhabit, so the measures of sustainability are less obvious. If space is a lifeless vacuum, what is it that we want to protect and prioritize when operating there? The financial investments of space startups? The integrity of existing spacecraft? The usability of specific orbits? The lives of astronauts? The view of the night sky? All of the above? How do we measure these things, and how do they influence one another?

To help answer these questions, NASA is soliciting outside research and analysis from U.S.-based universities and nongovernmental organizations. It will provide up to $300,000 for between one and three research projects examining the social, economic, and policy elements of space sustainability.

“It’s going to be exciting to see how that blends into the implementation of the strategy, the concept of this framework really pulling together all the elements we feel space sustainability needs and how they’re interrelated,” Weeden says. “And once you understand that, it helps set the baseline for technical investments for NASA.”

One such technical investment might be tools that can help better identify and track space debris. NASA estimates that there are about 100 million pieces of space debris that are too small to be tracked. The Department of Defense’s Space Surveillance Network uses mostly radar to monitor objects in low Earth orbit that are larger than about 4 inches, but anything smaller goes under the radar. Traveling at up to 18,000 miles per hour, these specks of shrapnel can cause major damage should they collide with spacecraft. Recently China’s space agency announced its Tiangong space station lost power after being struck by space debris.

There are already about 10,000 satellites orbiting Earth right now, and this number could grow to 60,000 by 2030. As we put more hulking metal machines into the sky, we inevitably produce more space debris. Some gets left behind intentionally as dead satellites or cast-off parts of rockets. Other clouds of debris are the remnants of catastrophic collisions of the past. In 2009, the American Iridium-33 satellite collided with the Russian Kosmos2251 satellite, spewing more than 2,300 pieces of debris into orbit—and that’s just the stuff that’s big enough to be tracked. As space becomes more crowded, the chances of collisions go up. And each collision produces more debris, cranking up the risk factor even more in a vicious cycle. It is, well, unsustainable.

So when does the risk become too high? Similarly, how do space operators weigh long-term space sustainability with short-term mission interests? A satellite startup, for example, may be able to save money by launching at a particular time or into an orbit that has negative lasting consequences for the space environment. NASA hopes to “signal to the world what the agency’s priorities are in space sustainability.” Where NASA leads, it hopes others will follow. On Earth, such an opportunistic actor could be penalized by ruling authorities, but governing gets trickier once you escape the grip of gravity.

“No one owns space,” Weeden says. “You can’t have state-by-state control. So we have to work by necessity and build practices, norms of behavior, and a common understanding of where things are and feed that into our operations.”

The director of space sustainability will help promote these norms within NASA, as well as internationally and with the general public. It’s a tall order. To most people, space seems too big to become crowded, and too close to ever be out of reach. We take it for granted. “This is like global warming in the sense that we see it coming,” Darren McKnight, senior technical fellow at spacecraft and debris-tracking company LeoLabs, told National Geographic. “But no one wants to act until it’s really a problem.”

As on Earth, convincing everyone that space cannot be humanity’s dumping ground requires a clear and sustained messaging shift. Weeden says effective communication skills will be paramount for the director of space sustainability. “This person will be selected to have that broad overview, understand what the framework means—not just the technologies, not just the operations, but also the public policy and economic questions, someone who can knit this whole thing together and be a voice for NASA internally and externally on the topic.”

After NASA puts forward its sustainability plan for low-Earth orbit, it will set sights on protecting the next frontiers: the moon and, eventually, deep space. “Humanity is going back to the moon in earnest,” Weeden says. “So we need to get ahead of those questions right away, once we’re well established here.”