Rockets are notoriously finicky. Old friend “physics” leaves rockets with almost no room for error, and even then, only a small fraction of their weight makes it into orbit.
In theory, there are other ways to accomplish this—such as a space elevator, a centrifuge, or a long chain extending from a satellite to retrieve cargo from Earth. (Blue Origin once spent time considering the latter, and the idea later became a plot element in a Neal Stephenson novel.)
Another idea traces back to Jules Verne: using a cannon to launch a projectile into space.
Based in Alameda, California, the startup Longshot Space Technology is doing exactly that. Co-founders and CEO Mike Grace and CTO Nato Saichek believe they can apply a proven technology to meet the urgent demand for space launches. The company has raised approximately $20 million from venture investors to advance this mission.
Grace said that in cutting-edge technology fields, “you can either create something highly innovative or tackle something extremely difficult—you can’t do both.” He cited SpaceX as an example, noting that the company “scaled up technologies that had traditionally been de-risked.” He explained that just as SpaceX built upon NASA’s rocket research, Longshot will replicate this approach with multiple-stage railguns—designs previously used during World War II and in 1960s research projects to provide additional acceleration to projectiles within gun barrels.
The Longshot concept involves compressing all the work done by a rocket's first stage into a single, reusable ground-based accelerator. Imagine it as a horizontal steel pipe laid along the ground, with high-pressure gas tanks connected at various points along its length. As the projectile is launched and travels down the barrel, these tanks release gas at precisely timed intervals to accelerate it—currently reaching up to Mach 4.
The company is currently firing a 70-foot-long, 6-inch-diameter gun at a test site near Barstow, California, and says it can accelerate projectiles to near-supersonic speeds. Soon, the company expects to activate a 140-foot-long, 30-inch-diameter gun at its Alameda test site. Following that, the company plans to build a 328-foot-long, 30-inch-diameter gun and intends to extend it to approximately 3,000 feet—making it the largest gun on Earth. The team says it will be capable of launching a 220-pound payload at Mach 8.
These cannons allow Longshot to continuously validate its technology while generating revenue by providing hypersonic testing for the U.S. military, which has already awarded the company several contracts. Grace envisions building such a cannon at U.S. military bases, such as Fort Bliss, to make it part of the infrastructure for testing next-generation U.S. interceptors. (And no, these cannons do not need to be angled upward. Longshot’s projectile is a lifting body, meaning its shape generates lift, allowing it to climb aerodynamically after exiting the barrel.)
Grace asked, "If you want to practice shooting down hypersonic missiles from China or Russia, wouldn't you prefer not to spend $30 million?" He replied, "This is a way to create a hypersonic 'flying saucer' target for $500,000 or even $250,000—throw it out and shoot it down, with extremely high speed and very low cost."
However, the ultimate goal remains placing heavy payloads into space. The team is confident that the current design can be scaled to accelerate payloads to 5 kilometers per second—over 11,000 miles per hour. If the payload itself is equipped with a propulsion system, this speed would be sufficient to reach space, effectively turning the payload into the rocket’s second stage. But achieving this would require a cannon 10 kilometers long and nearly 10 feet in diameter. As you might imagine, one of the company’s challenges is simply finding a suitable location for construction.
Saichek joked, "The challenge isn't building the thing—it's finding a place where they'll let you build it."
But if Longshot can realize its vision, the mathematical model for this approach is highly compelling: both system construction and fuel costs are low, and the system is highly reusable. Grace expects that, if everything goes well, they could reduce the cost of delivering payloads to space to an incredible $50 per kilogram (approximately $22 per pound). Given that the highly sought-after orbital data center industry needs prices to fall to around $300 per kilogram to get started, this means Longshot still has significant room to offer competitive pricing.
Some modifications would be required to launch spacecraft with this design and under these conditions, but satellite operators would be willing to try at this price point.
If you'd like to learn more about Longshot itself—while also exploring dozens of startups, listening to their pitches, and attending talks from guest speakers across four different stages—join us at Disrupt in San Francisco from Tuesday through Thursday. Learn more here.