NASA and Aerojet Rocketdyne have begun tests on the most powerful solar-electric engines, which are expected to revolutionize space propulsion, according to a press release from NASA. The traditional method of space propulsion relies on chemical thrusters, which consume large amounts of fuel and limit the speed and range of spacecraft. Electric propulsion, on the other hand, significantly reduces fuel consumption and enables faster and more efficient space travel.
What is solar-electric thrust?
Solar-electric thrust involves using electricity to ionize inert gases like xenon or krypton. These ions are then accelerated by magnetic or electrostatic fields, creating high speeds. Although this method lacks the fiery effects of traditional rocket engines, it is highly efficient. The electricity needed for ionizing the gases can be obtained from sunlight, which is abundant throughout the solar system. Electric engines also provide the flexibility to change spacecraft speed and trajectory during missions.
NASA has previously experimented with solar-electric propulsion during its Dawn mission. However, the agency is now preparing to demonstrate a more powerful version that will be installed on the power and thrust element (PPE) of Gateway, a space station that will orbit the moon. The Gateway station is a 60 kW-class spacecraft, with 50 kW dedicated to propulsion. Aerojet Rocketdyne has developed an electric propulsion system called Advanced Electric Propulsion System (AEPS), which has a power output of 12 kW, twice as much as the most advanced electric propulsion system currently available.
Prior to being integrated into the PPE on Gateway, the AEPS must undergo tests to ensure it meets the necessary requirements. NASA and Aerojet Rocketdyne have initiated annual tests on a sample engine, which is identical to the engines that will be used on Gateway in 2025. The engine is subjected to extreme conditions simulating the launch and flight of the Artemis mission, including blows, vibrations, and temperature variations. In 2024, another sample engine will be tested to simulate ascent to orbit and transition to lunar orbit. All tests are conducted in the vacuum chambers at NASA Glenn Research Center.
Rochit Shastri, Chief Engineer of AEPS, described the testing campaign as a crucial step before using the engines on Gateway. The successful development of the solar-electric engines will mark a significant advancement in space propulsion technology and pave the way for future space missions.