A Sept. 5 article in the journal Nature described how AME assistant professor Aaron Rosengren's research might help clean up the huge amount of space junk in Earth's orbit.
Rosengren's work centers on the idea of using the gravitational pulls of the sun and the moon -- known as resonances -- to put satellites on a path to destruction. He first came across the idea when studying satellites in medium Earth orbit. These travel at altitudes anywhere between about 2,000 kilometers up, where low Earth orbit ends, and 35,000 kilometers up, where geostationary orbits begin.
Satellites in low Earth orbit can be forced to re-enter the atmosphere, thereby disposing of them. Satellites in the geostationary region, which is less heavily populated, can be moved to "graveyard" orbits, where they would never interact with other objects. However, satellite trajectories in MEO can be unstable over the long term because of gravitational resonances.