Engineering the
Path Off-World
United Space Explorers designs and tests liquid rocket engines across three propellant families, builds the heavy-lift vehicles they power, and is constructing an orbital network built to reach the places fiber never will.
Four Disciplines.
One Flight Stack.
From the propellant in the tank to the network the spacecraft talks to once it gets there — we build the chain end to end.
Propulsion
Three propellant families — kerolox, methalox, and hydrolox — each engineered for a distinct mission profile, from booster thrust to deep-space efficiency.
View Engines 02Launch Vehicles
Horizon, our heavy-lift flagship, and Pathfinder, a fully reusable medium-lift vehicle — both built around the engines above.
View Vehicles 03Satellites
The Sentinel platform family — small, medium, and large buses — built at production speed inside our Denver satellite works.
View Satellites 04Aether Network
A laser-meshed constellation in low Earth orbit, built to bring low-latency broadband to the places terrestrial networks can't reach.
View AetherThree Propellants.
Purpose-Built.
Every mission profile has a different propellant problem. We'd rather build the right engine than force one engine to solve all of them.
Forge
Dense, storable, and built for raw first-stage thrust. Forge is the booster workhorse behind Horizon Heavy.
230,000 LBF · ISP 312S VAC
View SpecificationsEmber
Full-flow staged combustion, rated for 40 reuses, and ISRU-relevant. Ember flies both stages of Pathfinder.
215,000 LBF · ISP 358S VAC
View SpecificationsGlacier
The highest efficiency we build. A closed expander cycle that powers Horizon's upper stage to GTO and beyond.
90,000 LBF · ISP 449S VAC
View SpecificationsHorizon Heavy-Lift
A two-stage heavy-lift vehicle built around seven reusable Forge engines and a single Glacier upper stage. Horizon is sized for the missions that need both raw mass to orbit and the precision to get to GTO and cislunar space.
| Height | 71 m |
| Payload to LEO | 34,000 kg |
| Payload to GTO | 12,500 kg |
| Status | Qualification Testing |
A Mesh of Light Around the Earth
Aether is a laser-meshed low Earth orbit constellation, designed to deliver broadband to maritime, aviation, rural, and government users wherever terrestrial fiber doesn't reach. The first six satellites are already on orbit.
Latest From USX
View All NewsUSX Selected to Supply Upper-Stage Engines for National Security Launch Program
May 12, 2026
First Six Aether Network Satellites Reach Orbit
March 4, 2026
Pathfinder Completes Fourth Booster Reflight in Under 30 Days
January 22, 2026
We're Building the
Next Launch Manifest
From propulsion test stands to satellite integration floors, we're hiring engineers and technicians who'd rather build flight hardware than talk about it.