Impulse Space builds spacecraft and propulsion systems that take over after a launch vehicle reaches orbit, moving, hosting and deploying payloads for commercial operators and government agencies. Its flight-proven Mira spacecraft handles agile maneuvers and smaller payloads, while the planned Helios kick stage is designed for larger transfers to higher-energy orbits. The company announced a $308 million Series D extension, bringing the combined round to $808 million.
The workflow starts with a customer’s payload riding a rocket into an initial orbit. Mira can then host the hardware, deploy it at another location or perform responsive maneuvers; the company lists payload capacity of up to 300 kilograms. For longer routes, Helios is designed to pair with a launch vehicle and use its own propulsion to carry payloads from low Earth orbit toward medium Earth orbit, geostationary orbit, lunar trajectories or Earth escape. Impulse markets dedicated, shared and rideshare mission configurations.
The vehicles serve complementary operating profiles. Impulse says Mira uses high-thrust chemical propulsion and has flown three missions, while Helios is intended to move larger payloads from low Earth orbit to geostationary orbit in less than a day and is scheduled for its first flight in 2027. Its newer Electra system adds efficient electric propulsion for continuing work such as stationkeeping, leaving chemical propellant available for faster orbit changes when timing matters.
The extension follows the $500 million initial Series D that Impulse announced in June. Existing investors 137 Ventures, BANNER VC, DFJ Growth, Linse Capital, Lux Capital and Valor Equity Partners participated in the additional financing. Impulse said the money will support product development and team growth; it did not disclose a valuation. The company also appointed former VIZIO finance chief Adam Townsend as its first chief financial officer.
The company is scaling around both commercial missions and government work. Impulse said it has more than doubled its headcount over the past year. It also cited Helios’s selection for the United States Space Force’s National Security Space Launch Phase 3 Lane 1 program and a separate $28 million Space Systems Command contract extension covering two additional missions that will use Mira spacecraft.
Fresh capital now has to support several commercialization steps at once: increasing Mira capacity, bringing Helios to its first flight, starting Caravan shared missions and demonstrating Electra in orbit. The operating test is whether Impulse can turn that widening product line and its government awards into a repeatable delivery cadence while introducing multiple new systems.