There’s a lot of traffic in space these days. Experts are starting to worry about a celestial traffic jam. The growth of the private space economy means many more satellites in orbit, especially low-earth orbit, or LEO. That increases collision risk. As a result, space traffic management is becoming one of the most important governance issues of the 21st century.
Fortunately, thanks to a new agreement between NASA and SpaceX, orbit just became a little safer.
The accord between the U.S. civil space agency and Elon Musk’s ambitious rockets-for-profits enterprise “enables a deeper level of coordination, cooperation, and data sharing, and defines the arrangement, responsibilities, and procedures for flight safety coordination.” One of the most important provisions addresses the possibility of conjunctions, “defined as a close approach between two objects in space, usually at very high speed.”
Whenever there’s a conjunction between two space objects, collision risk is high. Satellites in orbit move at phenomenal speeds, so collisions can be catastrophic, resulting in the destruction of both assets. But that’s only the start of the problem. The debris from collisions also poses a threat. A collision produces debris, which increases collision risk, which results in more collisions, and hence more debris. It’s a vicious circle, which could quickly render LEO unusable. This doomsday scenario is called Kessler syndrome, after the NASA scientist who first discussed it.
But LEO isn’t a junkyard quite yet. And if the NASA-SpaceX agreement is the start of greater public-private cooperation in space traffic management, we can keep orbit relatively clean. This agreement is a great first step.
SpaceNews reports, “SpaceX has agreed to maneuver any of its Starlink satellites that come close to the International Space Station or other NASA spacecraft in low Earth orbit as part of an agreement between the agency and the company.” In other words, public-sector assets have right-of-way. SpaceX’s Starlink satellites, part of an orbital system for internet access, will maneuver any time the likelihood of conjunction is sufficiently high.
One way to look at this is as a coordination problem. Both NASA and SpaceX would be better off if one party agreed to maneuver while the other party maintained its trajectory. If they both maneuver, the chance something goes wrong gets much higher. Both parties gain from a clearly understood rule about who has the burden of avoidance. In this case, the rule came through voluntary agreement. Score one for private-public partnerships.
Some basic economics can also help us understand the agreement. Orbital trajectories are common-pool resources. It’s hard to prevent companies or governments from placing assets in orbit. The lack of excludability suggests we should expect lots of space traffic. But two assets can’t occupy the same space at the same time. Orbits are rivals in use: the more used by one party, the less must be used by other parties. This implies there’s an externality problem with space assets. SpaceX doesn’t have an incentive to account for the costs it imposes on NASA by putting an additional asset into orbit and vice versa.
All externality problems are property rights problems, as Ronald Coase taught us. The question is, who has the right to use an orbital trajectory? Parties can and will bargain over use rights, provided it’s not too costly to reach an agreement. In this case, because the number of parties is small, and uncluttered orbits are in both of their interests, voluntary standards-setting works.
Space junk isn’t solely, or even mainly, a private-sector problem. Of the debris currently in orbit, most was created by governments, not businesses. It’s a relic of the 20th-century space race between the United States and the Soviet Union. While space debris might not be the business’s fault, it is their problem. If they want to make money in space, they need to deal with the situation as-is. Thankfully, SpaceX appears willing to play ball. We should hope for more public-private agreements such as this.
Alexander William Salter is an associate professor of economics in the Rawls College of Business at Texas Tech University, the comparative economics research fellow at TTU’s Free Market Institute, and a Young Voices senior contributor. Follow him on Twitter @alexwsalter.
