Two Vehicles.
Every Orbit That Matters.
Horizon Heavy carries the mass; Pathfinder carries the cadence. Between them, the two vehicles cover everything from rapid smallsat deployment to GTO and cislunar delivery.
Horizon Heavy
71M · Partially ReusablePathfinder
48M · Fully ReusableHorizon Heavy
A two-stage heavy-lift vehicle built around seven reusable Forge-1 engines and a single Glacier-90 upper stage. Horizon is sized for missions that need both raw mass to orbit and the precision to reach GTO and cislunar space.
| Configuration | 2-Stage, Partially Reusable |
| Height / Diameter | 71 m / 5.4 m |
| Stage 1 | 7× Forge-1 (Reusable) |
| Stage 2 | 1× Glacier-90 |
| Payload to LEO (Reusable) | 26,000 kg |
| Payload to LEO (Expendable) | 34,000 kg |
| Payload to GTO | 12,500 kg |
| Fairing | 5.2 m dia / 145 m³ |
| Status | Qualification Testing |
Pathfinder
Pathfinder is a fully reusable, fully methalox medium-lift vehicle — nine Ember-200 engines on the booster, one vacuum-optimized Ember-200V on the upper stage. It's the vehicle carrying the flight-test cadence that's putting boosters back on the pad within a day of landing.
| Configuration | 2-Stage, Fully Reusable |
| Height / Diameter | 48 m / 4 m |
| Stage 1 | 9× Ember-200 (Reusable) |
| Stage 2 | 1× Ember-200V (Reusable) |
| Payload to LEO | 13,000 kg |
| Payload to SSO | 9,200 kg |
| Booster Turnaround | 24-Hour Reflight Target |
| Status | Active Flight Test Campaign |
Mission Profiles
Where each vehicle does most of its work.
Low Earth Orbit
Both vehicles fly here — Sentinel deployment, Aether Network buildout, and rapid-cadence smallsat missions.
Sun-Synchronous
Pathfinder's primary lane for Sentinel-M Earth observation missions needing consistent lighting conditions.
Geostationary Transfer
Horizon's domain — Sentinel-L national security and GEO communications payloads.
Cislunar & Beyond
Horizon flying expendable, for government and science payloads headed past geostationary orbit.
How a Booster Comes Home
Five phases between stage separation and the next time that same booster flies.
Boostback Burn
After stage separation, the booster reignites a subset of engines to reverse its trajectory back toward the landing zone.
Re-Entry Burn
A second burn slows the booster as it re-enters the dense lower atmosphere, limiting aerodynamic heating on the structure.
Grid Fin Guidance
Deployed grid fins steer the booster toward the landing site using atmospheric control surfaces alone.
Landing Burn
A final burn on a subset of engines decelerates the booster to a near-stationary touchdown.
Touchdown & Recovery
Landing legs absorb touchdown loads; the booster is secured and transported back to the integration facility for inspection.
Ready to Manifest
a Payload?
Tell us the mass, the orbit, and the timeline. We'll tell you which vehicle gets you there.