The dawn of stationary spacecraft may soon be behind us as Portal Space Systems, spearheaded by propulsion expert Jeff Thornberg, sets its sights on revolutionizing in-space transportation with its groundbreaking Supernova satellite bus. Think of it as maneuverability-as-a-service—a technological marvel poised to propel transfers from low Earth orbit to geostationary orbit in a matter of hours.
Supernova, boasting a payload-agnostic design and an impressive orbital lifespan of five years with continuous maneuverability, stands in stark contrast to legacy spacecraft, which are typically restricted to carrying only the propulsion necessary to maintain their designated orbits.
Portal has meticulously engineered an innovative solar-thermal propulsion system that unleashes a remarkable delta-V of 6 kilometers per second. This system opens up a realm of possibilities, facilitating rapid transfers to cislunar space and providing maneuverable assets for missions of national significance.
With its roots in the space industry, Portal was founded by a trio of veterans: Jeff Thornburg, Ian Vorbach, and Prashaanth Ravindran. Thornburg’s illustrious career, spanning nearly three decades, reads like a chronicle of the space industry itself, encompassing stints at major aerospace organizations like the Air Force, Aerojet, SpaceX, Stratolaunch, and Amazon’s Project Kuiper.
Reflecting on his career path, Thornburg realized that the industry’s future lay beyond affordable, rapid, and reliable launch, the domain that SpaceX had conquered. He identified two significant trends: the increasing number of spacecraft in orbit, raising the likelihood of on-orbit collisions, and the growing national security imperative for responsive space capabilities and satellites that could maneuver ‘without regret.’
Supernova emerges as a game-changer, addressing the limitations of traditional satellites that are not designed for extensive orbital maneuvering. It’s part of a new generation of spacecraft that prioritizes agility and adaptability.
Portal has invested significant effort in developing Supernova’s propulsion system in-house. The solar-thermal system draws inspiration from NASA and the Department of Defense’s legacy technologies, while incorporating innovative subsystems to optimize mission performance. One such innovation is the company’s proprietary heat exchanger, which enhances the system’s efficiency and extends its lifespan.
Thornburg attributes the surge in demand for maneuverable spacecraft to two primary factors: the proliferation of LEO constellations that require navigation and the growing strategic significance of space, particularly in light of China’s increasing presence. The confluence of these factors has created an unprecedented opportunity.
Portal has secured undisclosed venture funding and has received over $3 million in awards from the Space Force and the DOD, including a direct-to-phase II SBIR specifically aimed at developing responsive space operations. The company’s immediate goal is to conduct an in-flight demonstration in late 2025 or early 2026.
Beyond that mission, Portal has ambitious plans to expand its team from the current 25 to 200 within the next 25 years. It envisions scaling up manufacturing to support the production of multiple spacecraft annually following the successful demonstration of Supernova.
