Pushing the limits of sub-kilowatt electric propulsion technology for space mission concepts

NASA has developed a sophisticated propulsion expertise to facilitate future planetary exploration missions utilizing small spacecraft. Not solely will this expertise allow new kinds of planetary science missions, certainly one of NASA’s business companions is already making ready to make use of it for an additional objective—to increase the lifetimes of spacecraft which are already in orbit.

Figuring out the chance for trade to make use of this new technology not solely advances NASA’s aim of expertise commercialization, it might doubtlessly create a path for NASA to amass this essential expertise from trade to be used in future planetary missions.

The brand new expertise

Planetary science missions utilizing small spacecraft can be required to carry out difficult propulsive maneuvers—resembling reaching planetary escape velocities, orbit seize, and extra—that require a velocity change (delta-v) functionality effectively in extra of typical business wants and the present state-of-the-art. Due to this fact, the #1 enabling expertise for these small spacecraft missions is an electric propulsion system that may execute these high-delta-v maneuvers.

The propulsion system should function utilizing low energy (sub-kilowatt) and have high-propellant throughput (i.e., the aptitude to make use of a excessive total mass of propellant over its lifetime) to allow the impulse required to execute these maneuvers.

After a few years of analysis and growth, researchers at NASA Glenn Analysis Middle (GRC) have created a small spacecraft electrical propulsion system to fulfill these wants—the NASA-H71M sub-kilowatt Corridor-effect thruster. As well as, the profitable commercialization of this new thruster will quickly present not less than one such resolution to allow the following era of small spacecraft science missions requiring as much as a tremendous 8 km/s of delta-v.

This technical feat was achieved by the miniaturization of many superior high-power solar electrical propulsion applied sciences developed over the past decade for purposes such because the Energy and Propulsion Factor of Gateway, humanity’s first space station across the moon.

Advantages of this expertise for planetary exploration

Small spacecraft utilizing the NASA-H71M electrical propulsion expertise will be capable to independently maneuver from low-Earth orbit (LEO) to the moon and even from a geosynchronous switch orbit (GTO) to Mars.

This functionality is particularly outstanding as a result of business launch alternatives to LEO and GTO have turn into routine, and the surplus launch capability of such missions is usually bought at low value to deploy secondary spacecraft. The flexibility to conduct missions that originate from these near-Earth orbits can significantly enhance the cadence and decrease the price of lunar and Mars science missions.

This propulsion functionality will even enhance the attain of secondary spacecraft, which have been traditionally restricted to scientific targets that align with the first mission’s launch trajectory. This new expertise will allow secondary missions to considerably deviate from the first mission’s trajectory, which is able to facilitate exploration of a wider vary of scientific targets.

As well as, these secondary spacecraft science missions would usually have solely a brief time frame to gather information throughout a high-speed flyby of a distant physique. This larger propulsive functionality will permit deceleration and orbital insertion at planetoids for long-term scientific research.

Moreover, small spacecraft outfitted with such vital propulsive functionality can be higher geared up to handle late-stage modifications to the first mission’s launch trajectory. Such modifications are continuously a prime danger for small spacecraft science missions with restricted onboard propulsive functionality that rely upon the preliminary launch trajectory to succeed in their science goal.

Business purposes

The megaconstellations of small spacecraft now forming in low-Earth orbits have made low-power Corridor-effect thrusters probably the most considerable electrical propulsion system utilized in space at the moment. These programs use propellant very effectively, which permits for orbit insertion, de-orbiting, and a few years of collision avoidance and re-phasing.

Nonetheless, the cost-conscious design of those business electrical propulsion programs has inevitably restricted their lifetime functionality to usually lower than just a few thousand hours of operation and these programs can solely course of about 10% or much less of a small spacecraft’s preliminary mass in propellant.

In contrast, planetary science missions benefiting from the NASA-H71M electrical propulsion system expertise might function for 15,000 hours and course of greater than 30% of the small spacecraft’s preliminary mass in propellant.

This game-changing functionality is effectively past the wants of most business LEO missions and comes at a value premium that makes commercialization for such purposes unlikely. Due to this fact, NASA sought and continues to hunt partnerships with corporations creating revolutionary business small spacecraft mission ideas with unusually giant propellant throughput necessities.

One accomplice that can quickly use the licensed NASA electrical propulsion expertise in a business small spacecraft software is SpaceLogistics, an entirely owned subsidiary of Northrop Grumman. The Mission Extension Pod (MEP) satellite servicing automobile is provided with a pair of Northrop Grumman NGHT-1X Corridor-effect thrusters, whose design relies on the NASA-H71M.

The small spacecraft’s giant propulsive functionality will permit it to succeed in geosynchronous Earth orbit (GEO) the place it is going to be mounted on a far bigger satellite. As soon as put in, the MEP will function a “propulsion jet pack” to increase the lifetime of its host spacecraft for not less than six years.

Northrop Grumman is presently conducting a protracted length put on take a look at (LDWT) of the NGHT-1X in GRC’s Vacuum Facility 11 to display its full lifetime operational functionality. The LDWT is funded by Northrop Grumman by way of a completely reimbursable Area Act Settlement. The primary MEP spacecraft are anticipated to launch in 2025, the place they are going to lengthen the lifetime of three GEO communication satellites.

Collaborating with U.S. trade to search out small spacecraft purposes with propulsive necessities just like future NASA planetary science missions not solely helps U.S. trade in remaining a worldwide chief in business space programs however creates new business alternatives for NASA to amass these essential applied sciences as planetary missions require them.

NASA continues to mature the H71M electrical propulsion applied sciences to increase the vary of knowledge and documentation accessible to U.S. trade for the aim of creating equally superior and extremely succesful low-power electrical propulsion gadgets.