Electric propulsion systems work by accelerating particles such as ions, producing a distinctive blue glow. They’re a key part of expanded space exploration because, though they generate less thrust than the chemical rockets that generally push spacecraft into orbit, they also require much less fuel.

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For long-term space missions outside of planetary gravitation, that efficiency becomes more important than raw power. Electric propulsion has been used in a number of deep-space robotic exploration missions, including the Dawn mission that explored Ceres, a small “proto-planet” between Mars and Jupiter.

The new system, NASA said, should be 10 times more fuel efficient than a chemical rocket, and twice as powerful as existing electric systems. A potential application for the updated system could be in the Asteroid Redirect Mission (ARM), which aims to detach a chunk of a near-Earth asteroid and redirect it into orbit around the Moon for research.

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Aerojet Rocketdyne may not have the PR pizzazz of Elon Musk’s SpaceX or Jeff Bezos’ Blue Origin, but it’s a longstanding and important player in commercial space services and engineering. It built the engine for the now-retired space shuttle. Its AR1 engine is in the running, alongside an engine from Blue Origin, to replace the politically contentious Russian-built RD-180 engine in rockets that launch satellites and exploration missions.

Aerojet Rocketdyne will have 36 months to deliver their new engine. NASA said it would work in conjunction with recently improved solar generating systems.