Air-Breathing Satellites Offer Potential Solution to Low Earth Orbit Drag
A novel approach to satellite stabilization-using atmospheric drag as a resource-is gaining traction, potentially unlocking benefits for communications and Earth observation. While seemingly counterintuitive, the concept of “air-breathing” satellites aims to overcome the limitations of current Low Earth Orbit (LEO) technology, where atmospheric drag steadily degrades orbital altitude.
LEO presents a unique challenge: despite the vacuum of space, sufficient air resistance exists at speeds exceeding 28,000 km/h (17,000 mph) to cause orbital decay.Traditionally, satellites maintain altitude by “coasting on momentum.” However, a new strategy proposes deliberately operating in very low orbits-below 300 km (186 miles) but still above the Karman line-and actively utilizing the atmosphere. This approach promises advantages like reduced latency for communications and higher resolution for Earth observation, but requires a method to counteract the increased drag.
past attempts at maintaining orbit in these extremely low altitudes have relied on conventional Xenon-fueled ion engines, as demonstrated in previous missions.However, the limited supply of Xenon results in short satellite lifespans. The air-breathing satellite concept seeks to address this by leveraging the thin atmosphere itself as reaction mass for solar-electric ion engines, requiring only minimal thrust for stabilization.
Challenges remain, including the corrosive effects of monoatomic oxygen at these altitudes. A recent video by Eager Space details these hurdles and various proposed solutions.
Developers exploring this technology may benefit from the expertise of [Jay Bowles], whose air-breathing ion thrusters have been previously highlighted by Hackaday (https://hackaday.com/2023/06/12/high-voltage-ion-engines-take-trip-on-the-high-seas/ and https://hackaday.com/2022/09/19/multi-stage-ion-thruster-holds-exciting-promise/).
