How Satellites Can Utilize Magnetic Fields to Prevent Collisions

Utilizing magnetic fields to maneuver satellites could significantly enhance the longevity of space exploration missions and reduce the risk of collisions between spacecraft.

Currently, most space missions and artificial satellites depend on propellant for movement in space, which limits their operational lifetimes due to fuel depletion. An innovative alternative, known as electromagnetic formation flight (EMFF), employs renewable energy sources like solar panels to power onboard electromagnetic coils. These coils generate magnetic fields that can theoretically steer spacecraft through interactions with similar fields from adjacent satellites.

However, researchers have faced challenges with EMFF due to a phenomenon called electromagnetic coupling. The magnetic field from one satellite affects not just nearby satellites but all satellites in proximity, complicating coordinated movement among multiple objects.

A research team at the University of Kentucky has proposed a promising solution through a method called alternating magnetic field forcing (AMFF).

This technique enables two satellites to communicate and control each other’s trajectories without disrupting a third satellite. This is achieved by utilizing distinct interaction frequencies, allowing two satellites to coordinate on one frequency while maintaining communication with others on different frequencies.

The AMFF concept has been successfully tested on Earth instead of in space. The three satellites were positioned on specialized linear rails employing high-pressure air to create a low-friction environment. With the integrated laser ranging module, the satellites achieved precise travel distances and effective interactions as defined by the researchers.

The project team did not respond to interview requests. However, Alvar Saenz Otero, a researcher at the University of Washington, noted that this paper represents a significant advancement in a long-standing research area. “The complexity of a formation flight system increases significantly when transitioning from two to three satellites,” he explains.

Yet, Otero expresses skepticism about the immediate application of this technology for low-Earth orbit satellites, such as massive constellations like Starlink. “Our work on EMFF has primarily focused on deep space operations,” he adds.

Earth’s atmosphere can impact the frequencies utilized for EMFF or AMFF, introducing interference that complicates satellite control, he notes.

While it is currently feasible for three units to fly together and utilize magnetic fields for navigation, scaling this approach to manage thousands of satellites poses a formidable challenge. “This is not applicable at the constellation level,” remarks Ray Sedwick from the University of Maryland.

“Employing superconducting magnetic coils significantly extends the operational range of EMFF, but numerous technical challenges remain,” Sedwick explains, indicating that large-scale magnetic motion might still be on the horizon.