SAN FRANCISCO – Southern California startup Viridian Space Corp. is developing an electric propulsion system for spacecraft in very low Earth orbit that scoops up air for plasma thrusters.
The technology promises to extend the life of satellites and enable them to move around in orbit, Rostislav Spektor, Viridian CEO and former manager of the Aerospace Corp. electric propulsion laboratory, told SpaceNews.
Research on air-scooping electric propulsion began in the 1960s. Until recently, the idea was often dismissed because no one had succeeded in producing engines with enough thrust to offset the atmospheric drag.
“Everyone who has tried this up to now has failed because they just weren’t able to figure out how to make the system efficient enough,” Spektor said.
Since Viridian was founded in El Segundo, California, in 2021, Spektor and co-founder Matthew Feldman, a former Aerospace Corp. research engineer, have “improved the overall efficiency of our system to the point where prototype hardware tested in a vacuum chamber is working on efficiencies required to make it feasible,” Spektor said. “I believe we’re one of the first companies to demonstrate that.”
VLEO’s Promise
Very low Earth orbit, or VLEO, is attracting attention from startups, established aerospace companies and government agencies. Applications include high-resolution Earth observation, high-bandwidth communications and, for military satellites, the ability to maneuver extensively.
With air-breathing electric propulsion, Spektor said, satellites in VLEO could operate for a decade. “This is based on the components that are going into our propulsion system,” he said, adding that the company is largely relying on commercial-off-the-shelf hardware.
Still, it’s challenging to build a spacecraft to operate for 10 years in VLEO. Metal fatigue is one problem. Another is atomic oxygen.
“There are material-interaction issues, especially with solar panels and other satellite components,” Spektor said. “This is something that we’re actively addressing right now.”
Viridian plans to demonstrate its technology on a satellite in low-Earth orbit within three years. After the initial demonstration, Viridian will incrementally improve the technology to extend the operational lifespan and enhance performance.
Longer-term, the company plans to develop propulsion systems that can ingest and store extra propellant to enable a satellite to raise its orbit for satellite-servicing missions.
The in-space servicing, assembly and manufacturing “economy is nascent now, but it’s coming,” Spektor said. The propulsion concept could lead to reusable tugs that could, for example, “grab a piece of space junk and bring it down,” he added.
FUNDING
To date, Viridian has raised about $2.5 million in pre-seed funding. In an upcoming seed round, the startup seeks to raise money to demonstrate its technology in orbit.
The U.S. Air Force and National Science Foundation have awarded Small Business Innovation Research contracts to Viridian.