Startup Orbital Arc Unveils Revolutionary Satellite Thruster

A startup named Orbital Arc has announced plans to develop a new spacecraft thruster that promises to be up to 40 percent more power-efficient than existing models, while also significantly reducing fuel costs and weight. The innovative design utilizes naphthalene, a low-cost byproduct of oil refineries, enabling the thruster to weigh an eighth of the mass of traditional options. Founder Jonathan Huffman believes that this technology could revolutionize satellite operations and interplanetary missions.

Huffman describes the new thruster as a compact device, measuring approximately an inch across, yet capable of delivering the same thrust output as larger thrusters weighing several kilograms. This miniaturization could make it feasible for even the smallest low-Earth orbit satellites to utilize the technology, allowing for significant cost savings and operational efficiencies, particularly in avoiding space debris.

Innovative Engineering Behind the Thruster

Thrusters generally operate by generating and expelling plasma, which propels a spacecraft in the opposite direction. Current systems, like the popular Hall thrusters, use a magnetic field to trap electrons, which collide with noble gases like xenon to form plasma. Huffman’s approach, however, diverges from this model.

His background as a biotech consultant and a passion for science fiction led him to explore propulsion systems while designing technology for a video game. He identified a key limitation in traditional ion thrusters: increased thrust typically requires heavier thruster components. Huffman recognized that reducing thruster mass while maintaining thrust output could lead to significant advancements in propulsion technology.

The core of Orbital Arc’s design features a chip embedded with millions of micrometer-scale tips. These tips interact with naphthalene gas, causing the molecules to polarize as they pass. As they release electrons, the ions become positively charged and are propelled outwards, generating thrust. This mechanism eliminates the need for the plasma generation that traditional thrusters rely on, leading to substantial power savings.

Recent calculations indicate that the new thruster could provide a 30 to 40 percent increase in efficiency. In tests, just six of Orbital Arc’s tips produced approximately three times more ion current than a setup of 320,000 tips from a team at MIT.

From Concept to Reality: Next Steps for Orbital Arc

Currently, the prototypes developed by Orbital Arc contain only six tips, fabricated using microelectromechanical systems (MEMS) in a cleanroom environment at Oak Ridge National Laboratory. The next phase involves creating a full-scale chip version, along with the necessary components for the thruster assembly. Huffman anticipates that this will involve straightforward integration of a valve, wiring, and structural elements.

The startup aims to conduct rigorous testing, including vibration, radiation, and thermal cycling, to qualify the thruster for flight. Huffman is optimistic about having a commercial product within the next two years. He expects that small teams, such as startups and research groups, will be early adopters of the technology, even if it has not yet been flown in space.

Despite some skepticism from experts like Jonathan MacArthur at Princeton University, who emphasizes the importance of historical data in selecting propulsion systems, there is potential for missions using CubeSat technology to embrace this innovation. Other startups have seen recent success with new electric propulsion technologies, which may encourage customers to take a chance on Orbital Arc’s thrusters.

Huffman envisions a future where the integration of this lightweight thruster allows for significant reductions in spacecraft dry mass, enhancing mission capabilities and efficiency. By utilizing naphthalene, which costs around USD 1.50 per kilogram compared to USD 3,000 for xenon, Orbital Arc claims to achieve production costs at just 1 percent of traditional Hall thrusters.

While the journey from prototype to operational thruster is complex, Huffman remains committed to pushing the boundaries of propulsion technology. He aims to ultimately develop an ultra-light spacecraft bus, paving the way for ambitious missions that could redefine space exploration, including potential two-way human-rated missions to Jupiter.