NASA’s new propulsion technology improves the capabilities of small spacecraft for Future planetary missions and extends the operational Life of existing satellites. By partnering with commercial entities, NASA not only advances its technology commercialization goals, but also supports the global leadership of the U.S. space industry. Credit: Northrop Grumman
NASA‘s innovative propulsion technology powers small spacecraft exploration and extends satellite life, supporting U.S. leadership in space technology.
NASA has developed advanced propulsion technology to facilitate future planetary exploration missions using small spacecraft. Not only will this technology enable new types of planetary science missions, but One of NASA’s commercial partners is already preparing to use it for another purpose: extending the life of spacecraft already in orbit. Identifying the opportunity for industry to use this new technology not only advances NASA’s goal of commercializing technology, but could potentially create a pathway for NASA to acquire this important technology from industry for use in future planetary missions.
The new technology
Planetary science missions using small spacecraft will be required to perform difficult propulsion maneuvers, such as achieving planetary escape velocities, orbit capture, etc., which require velocity-shifting capability (delta- v) well beyond typical business needs and current conditions. -art. Therefore, the #1 enabling technology for these small spacecraft missions is an Electric propulsion system capable of executing these high delta V maneuvers. The propulsion system must operate at low power (sub-kilowatt) and have high propellant flow (i.e., the ability to use a high total mass of propellant over its lifetime) to allow the impulse required to execute these maneuvers.
After many years of research and development, researchers at NASA’s Glenn Research Center (GRC) have created a small spacecraft electric propulsion system to meet these needs: the sub-one-kilowatt Hall Thruster NASA-H71M. Additionally, the successful commercialization of this new thruster will soon provide at least one of these solutions to enable the next generation of small spacecraft science missions requiring up to an incredible delta-v velocity of 8 km/s. This technical feat has been accomplished through the miniaturization of many advanced high-power solar electric propulsion technologies developed over the past decade for applications such as the power and propulsion element of Gateway, the world’s first space station. humanity around the Moon.
Left: NASA-H71M Hall Effect Thruster on Thrust Rack 8 at the Glenn Research Center Vacuum Facility. Right: Dr. Jonathan Mackey adjusting the thrust support before closing and pumping the test facility. Credit: NASA
Benefits of this technology for planetary exploration
Small spacecraft using NASA-H71M electric propulsion technology will be able to independently maneuver from low Earth orbit (LEO) to the Moon or even from geosynchronous transfer orbit (GTO) to March. This capability is particularly noteworthy as commercial launch opportunities to LEO and GTO have become commonplace, and excess launch capacity from these missions is often sold at low cost to deploy secondary spacecraft. The ability to conduct missions from these near-Earth orbits can significantly increase the throughput and reduce the cost of science missions to the Moon and Mars.
This propulsion capability will also increase the range of secondary spacecraft, which have historically been limited to science targets aligned with the primary mission’s launch trajectory. This new technology will allow secondary missions to deviate significantly from the primary mission’s trajectory, making it easier to explore a wider range of scientific targets.
Additionally, these secondary spacecraft science missions would typically only have a short period of time to collect data during a high-speed flyby of a distant body. This greater propulsion capacity will enable the deceleration and orbital insertion of planetoids for long-term scientific studies.
Additionally, small spacecraft with such propulsion capability will be better equipped to handle subsequent changes to the primary mission’s launch trajectory. Such changes often pose a major risk for science missions of small spacecraft with limited onboard propulsion capability and which depend on the initial launch trajectory to achieve their science objective.
Commercial applications
The megaconstellations of small spacecraft now forming in low Earth orbits have made low-power Hall thrusters the most common electric propulsion system in space today. These systems use propellant very efficiently, allowing for orbit insertion, deorbiting, and many years of collision avoidance and rephasing. However, the cost-conscious design of these commercial electric propulsion systems has inevitably limited their lifespan to less than a few thousand operating hours and these systems can only handle about 10% or less of the initial mass of a small spaceship in thruster.
In contrast, planetary science missions benefiting from NASA-H71M electric propulsion system technology could operate for 15,000 hours and process more than 30% of the small spacecraft’s initial mass as propellant. This revolutionary capability goes well beyond the needs of most commercial LEO missions and comes with a higher cost that makes commercialization of such applications unlikely. Therefore, NASA has sought and continues to seek partnerships with companies developing innovative concepts for commercial small spacecraft missions with unusually high propellant flow requirements.
Northrop Grumman engineering model NGHT-1X Hall thruster operating in Vacuum Facility 8 at the Glenn Research Center. The NGHT-1X design is based on the NASA-H71M Hall effect thruster. Credit: Northrop Grumman
One partner that will soon use electric propulsion technology licensed from NASA in a commercial application for small spacecraft is SpaceLogistics, a wholly owned subsidiary of Northrop Grumman. The Mission Extension Pod (MEP) satellite servicing vehicle is equipped with a pair of Northrop Grumman NGHT-1X Hall effect thrusters, the design of which is based on the NASA-H71M. The small spacecraft’s large propulsive capacity will allow it to reach geosynchronous Earth orbit (GEO) where it will be mounted on a much larger satellite. Once installed, the MEP will serve as a “propulsion jet pack” to extend the life of its host spacecraft by at least six years.
Northrop Grumman is currently conducting a Long Life Wear Test (LDWT) of the NGHT-1X at GRC Vacuum Facility 11 to demonstrate its operational capability over its entire service life. The LDWT is funded by Northrop Grumman under a fully reimbursable Space Act agreement. The first MEP spacecraft is expected to launch in 2025, where it will extend the life of three GEO communications satellites.
Collaborating with U.S. industry to find applications for small spacecraft with similar propulsive requirements to future NASA planetary science missions not only helps U.S. industry remain a global leader in commercial space systems, but creates new opportunities commercial opportunities for NASA to acquire these important technologies when planetary missions require them. .
NASA continues to refine the H71M’s electric propulsion technologies to expand the range of data and documentation available to U.S. industry with the goal of developing equally advanced and high-performance low-power electric propulsion devices.
