CAPE CANAVERAL, Florida - NASA announced that the agency will invest $67 million in the development of Hall thrusters that create plasma rocket propulsion through the ionization of gas.
NASA awarded a $67 million Advanced Electric Propulsion System contract to Aerojet Rocketdyne, Inc. to design and develop an advanced electric propulsion system that could potentially increase spaceflight transportation fuel efficiency by 10 times over current chemical propulsion technology and more than double thrust capability compared to current electric propulsion systems.
NASA hopes to use the Advanced Electric Propulsion System for deep space missions, Mars missions, and to push an asteroid boulder into orbit around Earth's moon in the mid-2020's.
How Does a Hall Thruster Work?
A Hall thruster is a type of electric propulsion device that produces thrust by ionizing and accelerating a noble gas, usually xenon. While producing comparatively low thrust relative to conventional rocket engines, Hall thrusters provide significantly greater specific impulse, or fuel economy. This results in increased payload carrying capacity and a greater number of on-orbit maneuvers for a spacecraft using Hall thrusters rather than traditional rocket engines.
Hall thrusters trap electrons in a magnetic field and use them to ionize the onboard propellant. The magnetic field also generates an electric field that accelerates the charged ions creating an exhaust plume of plasma that pushes the spacecraft forward. When solar arrays are used to supplement the electrical power, a Hall thruster can be a part of an advanced Solar Electric Propulsion system that uses 10 times less propellant than equivalent chemical rockets.
NASA's first successful ion electric propulsion thruster was developed at Glenn Research Center in the 1950's. The first operational test of an electric propulsion system in space was Glenn’s Space Electric Rocket Test 1 which flew on July 20, 1964.
Recently, NASA engineers from Glenn and the Jet Propulsion Laboratory successfully tested a breakthrough, higher power Hall thruster design in a vacuum chamber on Earth to simulate the space environment. The design was then tested in outer space in 2015 aboard the USAF X-37B.
NASA has increasingly relied on solar electric propulsion for long-duration, deep-space robotic science and exploration missions to multiple destinations. The most recent use of this propulsion was during NASA’s Dawn mission which surveyed the giant asteroid Vesta and Ceres.