The challenge is to design a sufficiently efficient air intake system to collect as many of the scarce but highly-energetic air molecules found at the top of the atmosphere as possible, to fuel an electric thruster to compensate for the air drag that would otherwise pull a satellite down to Earth in a matter of weeks. This was the goal of an ESA project with Belgium’s Von Karman Institute and Politechnico di Milano, developing sophisticated software models to qualify an air intake-collector design as well as manufacturing a metal prototype.
The relatively simple machine — “no valves or complex parts” according to the ESA — basically sucks in the infrequent air particles and gases them up with heat and electricity. This lets the thruster shoot them out the back, providing a modest, but measurable, thrust (around 5 mph when all goes well). An Italian lab built and tested an actual prototype, running within a vacuum chamber to simulate the thin atmosphere, and saw that it really did work. New air-breathing propulsion systems may thus be the next big thing in spacecraft, opening a door into a new type of missions simply impossible with previous technology.
This ramjet technology having been proven by ESA in principle, such Very Low Earth Orbit, VLEO
The project was supported through ESA’s General Support Technology Programme, to convert promising concepts into space-ready products.
The European Space Agency (ESA) is testing an air intake collector, which is designed to harvest air particles when passing through the upper layers of the atmosphere. These particles are then used to fuel an ‘air-breathing’ electric thruster.
The aim is to help satellites to overcome atmospheric drag – that would otherwise pull a satellite down to Earth in a matter of weeks – and thus operate continuously in very low orbits (VLEO), ranging from 180 km to 250 km.
Satellites operating in very low orbit (VLEO) could have a lot of benefits, mainly for Earth observation, and also for civil and military communications. At lower altitudes, you can improve payload performance and increase image resolution, while reducing size and power requirements. In turn, these low-altitude satellites could play an important role in transmitting the Internet and other data networks.
The biggest technological challenge is to design a sufficiently powerful air intake collector, which would be able to collect as many of the scarce but highly-energetic air molecules found in the upper atmosphere as possible. They will then use to fuel an electric thruster to compensate for the air drag.
This air intake collector is designed to harvest sufficient air particles as it skims the top of the atmosphere to fuel an ‘air-breathing’ electric thruster. The aim is to help satellites to overcome atmospheric drag to operate on an ongoing basis in orbits from as low as 180 km to a maximum 250 km altitude.
The project was supported through ESA’s General Support Technology Programme, to convert promising concepts into space-ready products.
This air intake collector is designed to harvest sufficient air particles as it skims the top of the atmosphere to fuel an “air-breathing” electric thruster. The aim is to help satellites to overcome atmospheric drag to operate on an ongoing basis in orbits from as low as 180 km to a maximum 250 km altitude.
This ramjet technology having been proven by ESA in principle, such Very Low Earth Orbit, VLEO satellites could provide sharper resolution Earth-observing imagery and low-latency communication links in the future.
