New Satellite Engine Could Use Earth's Atmosphere to Stay in Orbit Indefinitely

Scientists have developed a concept for a satellite engine that could collect atmospheric gases at altitudes of 100-450 km and use them as fuel for a plasma thruster, potentially allowing satellites to remain in orbit indefinitely without carrying conventional propellant. The technology, called atmosphere-breathing electric propulsion (ABEP), has shown promise in laboratory tests and modeling, but faces significant engineering challenges, including corrosion from atomic oxygen and the need to adapt to constantly changing atmospheric conditions. While the basic concept is straightforward, practical implementation on an actual mission remains unproven.