The First Moon Spaceport Is Coming. But First We’ll Need Moon Traffic Control

The first lunar spaceport is planned for operation within two decades, according to NASA, but ensuring safe and efficient operations will require an advanced air traffic control system for the moon. Researchers from Texas A&M University, NASA Johnson Space Center, and Purdue University have outlined how such a system might function in a study published in Acta Astronautica.

The proposed system would manage multiple spacecraft sharing the same Near Rectilinear Halo Orbit (NRHO), an elliptical route that will serve as the primary approach for docking with the Gateway spaceport. This orbit passes within 1,000 miles of the moon’s north pole and swings out to 40,000 miles from the south pole. Diane Davis, an associate professor of space engineering at Texas A&M, noted that the NRHO provides a nearly stable, highly elongated orbit around the moon with consistent communication links to Earth and requires minimal propellant to maintain.

However, navigating this orbit presents significant challenges. Spacecraft in the NRHO will experience competing gravitational forces from Earth and the moon, and the proximity of multiple missions increases the risk of collisions or unintended course deviations. Precision maneuvering is essential to avoid such hazards, particularly given the limited fuel available for corrective actions.

To address these challenges, the research team proposed a coordinated approach where spacecraft maintain a "string of pearls" formation, sharing data and continuously recalculating their positions relative to the Gateway. This method ensures safe distances between vehicles and accounts for realistic navigation errors, thruster imperfections, and other disturbances. While this approach requires slightly more fuel to maintain precise orbits, the researchers found that the increased predictability is a worthwhile trade-off.

"The future of lunar exploration depends as much on the traffic management as it does on the rocket science," Davis stated.

The Gateway spaceport, a key component of NASA’s Artemis program, is expected to take several decades to construct. The proposed lunar air traffic control system would operate alongside it, ensuring safe and orderly operations in the NRHO. Further details on operational logistics, such as in-flight services, have not yet been announced.