Longshot Space Technology is developing a reusable, ground-based accelerator designed to propel cargo at high speeds before its own propulsion system carries it toward orbit. The approach could offer an alternative to relying solely on conventional rocket boosters.
The Alameda, California-based startup uses a multi-injection gun: as a projectile moves through a barrel, precisely timed bursts of compressed gas provide additional acceleration. The company says its current 70-foot test system has reached speeds approaching Mach 4.
Longshot plans to test a larger, 140-foot version, then scale up further. One proposed design, measuring 328 feet long with a 30-inch diameter, is intended to launch 220-pound payloads at up to Mach 8. Reaching space would require a much larger system--roughly 10 kilometers long--and a payload with its own propulsion.
The company estimates that, if the concept can be scaled successfully, its reusable system could eventually bring launch costs down to about $50 per kilogram. That figure remains a long-term target, and the approach would require spacecraft designed to withstand the launch conditions.
If the engineering and infrastructure challenges can be solved, ground-based acceleration could become a new part of the toolkit for making space access more affordable.
