Space is the final frontier. It represents a vast, boundless expanse that captures the human spirit’s innate desire for bold exploration but remains hard to access. In an era where outer space has become central to the vision of humanity’s future, core to providing global connectivity, and an emerging arena for geopolitics, reliable and cost-effective space transport has become the critical capability that defines success in the space economy.
Mastering space transport requires mastery of propulsion systems. As we came to this realization, it was natural to seek out the best of the best in the world of propulsion system design and engineering. This led us directly to Tom Mueller and Impulse Space, the company he founded in 2021 to meet the emerging need for high precision and responsive in-space mobility capabilities. As a founding employee of SpaceX and its longtime chief of propulsion systems, Tom led the development of the Merlin engines that have become the gold standard of modern rocket engines on the workhorse Falcon launch vehicles.
We are delighted to join Tom and the brilliant team he’s assembled as a new investor in Impulse’s $300 million Series C financing to define the role of in-space mobility in the rapidly growing space economy. As launch vehicle providers have increasingly specialized in taking payloads to orbit reliably and affordably, and as national security has expanded to include the space domain, the ability to maneuver spacecraft quickly and deliberately within and across orbits has become a pressing industry imperative. This is the domain of Impulse.
The company’s first two products, Mira and Helios, are high-performance space vehicles purpose-built for space defense and space transportation missions that require responsive in-orbit maneuverability executed with high precision. Both are leveraging innovative propulsion and engine designs. Mira is a compact interceptor that can sprint, dodge, and rendezvous within low, medium, and geostationary orbits in record time. Two successful on‑orbit missions have already proven Mira’s ability to host, rapidly transport, and inspect in-orbit spacecraft for customers. Helios is designed to carry up to five‑ton payloads from low Earth orbit (LEO) to geosynchronous orbits and beyond in a single day, orders of magnitude faster than existing orbit raising approaches. Together, these vehicles form the backbone of a responsive in‑space mobility layer that military and commercial operators have been demanding. And this is just the beginning for Impulse.
The need for high-performance in‑space maneuvering has never been more clear. The looming wave of specialized mass‑to‑orbit launch vehicles will demand agile logistics beyond the initial boost phase. Furthermore, as geopolitics moves from Earthbound battlefronts to space, adversaries are testing new tactics that require America and its allies to deploy fast propulsion for space-based surveillance and intercept capabilities. Impulse is uniquely poised to meet that need.
At DFJ Growth, we try to look around corners and catch a glimpse of the future before it becomes obvious. From our investments in industry-defining leaders like SpaceX and Anduril, we've witnessed firsthand how technology that bends the cost‑performance curve through innovative, first principles approaches to modern system design can reshape entire domains. Impulse is poised to do this for in-space mobility. We are thrilled to be saddling up for the ride as Impulse lights, and propels, the path forward.
Ad astra!
