Longshot Space: Reinventing Space Launch with Hypersonic Ground Guns

Imagine launching a payload into space not atop a towering rocket, but through a hypersonic “space gun” that accelerates objects to orbital velocity within a ten-kilometer barrel.

EcoAero had the opportunity to speak with Mike Grace, founder and CEO of the aerospace company Longshot, about how his team is redefining launch infrastructure with a low-pressure, multi-injection gas gun that promises to undercut traditional rockets by orders of magnitude.

Mike’s inspiration dates back to a Google Talk he saw nearly a decade ago, in which Dr. John Hunter described the concept of gigantic light-gas guns capable of achieving orbital speeds. After earning his bachelor’s and master’s degrees—and witnessing firsthand the steep learning curve of startups—Grace ranked his own ten initial venture ideas by difficulty and excitement, selecting what would become Longshot as both the hardest and most exhilarating option. He convinced his wife to back him as his first investor, lived on less than $1,000 a month for a year, built a Mach 1.8 potato-gun prototype, and ultimately secured $750,000 in U.S. Air Force grants to validate his concept.

“Failure is almost guaranteed with all startups, yeah, but the things that you learn are going to be so unique and important, and they’re going to carry forward with you, and people will have huge respect for you as a failed startup founder.”

At the heart of Longshot’s approach is a multi-injection gas accelerator that replaces a single, violent explosion with many smaller injections. This gentler acceleration reduces stress on the barrel, allowing construction from lighter materials—similar to those used in natural-gas pipelines—rather than the foot-thick steel walls of conventional artillery. It also delivers a slow, controlled acceleration that better preserves delicate payloads en route to space.

Compared to rockets, whose entire mass—including fuel, engines, and structure—must be lofted against gravity, Longshot’s design keeps both infrastructure and energy firmly on the ground. Mike argues that rockets owe their existence more to military imperatives—delivering warheads—than to orbital efficiency, and that the time is ripe for a first-principles reevaluation of how we access space .

Longshot envisions a tiered progression: achieving Mach 5 as a low-cost hypersonic test platform, Mach 10–15 for defense applications, and Mach 25 for orbital insertion. While U.S. defense contracts have funded initial demonstrations, Mike stresses his intent to pivot swiftly toward purely commercial space services, even as the company leverages government dollars for development.

Looking beyond launch, Mike foresees a specialized logistics ecosystem in space. Incoming payloads—standardized in mass, shape, and ballistic coefficient—would rendezvous with orbital “tugs” that redistribute fuel and transport satellites to their final destinations. Further downstream, space-based power and communications could become purchasable services, allowing satellite designers to focus solely on mission hardware rather than onboard support systems.

Regulatory hurdles and environmental considerations present the next challenges. Launch sites must be remote enough to accommodate significant sonic booms and frequent firings, while navigating complex FAA and land-use approvals. Additionally, Longshot must manage extremely high G-forces over a short launch distance—targeting payload survivability thresholds around 500 g, as opposed to competitors facing upwards of 15,000 g.

Longshot’s breakthrough at the intersection of ballistics and space access exemplifies the disruptive spirit EcoAero celebrates. As we continue to highlight sustainable, game-changing technologies shaping the future of aviation and space, EcoAero remains committed to showcasing pioneers like Mike Grace—championing the next generation of innovators who refuse to accept the status quo.

Image courtesy of Longshot Space, used with permission.