Sidereus has developed and is currently testing EOS: a fully reusable orbital launch vehicle for small satellites and payloads. EOS is an extremely versatile SSTO: it can be launched from anywhere, anytime, with zero or minimal launch infrastructures required. It is capable to deploy small satellites to low-earth orbit and bring payloads back to Earth at the cheapest price on the market.
The EOS, named after the Greek goddess of dawn, is an entirely different vehicle from any launcher ever developed, both in terms of technologies and in the concept of operations. Given its very small size (just 3 meters tall, 1 ton fully fueled), the launcher can be operated by a small crew and is powered by storable, safe, and green fuels.
The vehicle has autonomous guidance, like a drone, thus eliminating the risk of uncertainty in air traffic. In case of unforeseen events, the vehicle carries a commercially tested guided parachute (Parafoil), which can be activated any time during the flight, ensuring a safe return to the ground at the launch site.
With launch operations arranged in a day and the lowest price for smallsats as primary payloads, EOS becomes an orbital drone that can be used to deliver CubeSats, run experiments, tests, and commercial operations in space daily, anytime, anywhere.
EOS has a payload capacity to SSO of 12 kg, up to 20 kg for low orbits, with a time to orbit ranging from days to hours. EOS can be reused at least ten times with zero or minimal refurbishment needed.
EOS vehicle allows Sidereus to offer their clients:
- Fully customizable missions: clients’ CubeSats are positioned with extreme precision without using a space tug;
- Launch anytime you want: only one week from notification to launch date;
- Payload re-entry: clients can recover their payload safely, after a period ranging from 12 hours to 1 month into orbit;
- Constellation positioning and replenishment: accurate constellation positioning and fast replenishment in case of satellite failure;
- EOS vehicle as a platform: onboard payload integration to eliminate satellite bus costs;
- Iterative R&D: companies can test any component directly in space conditions on board EOS, with quick and customized launch campaigns;
- Drive-it-yourself: EOS vehicles can potentially be operated autonomously by the client.
EOS key technologies have already been demonstrated, from tanks to the engine and are currently undergoing their optimization and integration process. A first test flight to 500 m is expected by Q1 2025 to demonstrate flight control and safety. Between Q4 2025 and Q1 2026 a suborbital validation is currently planned, to later pave the way to the orbital flight expected by Q2 2026.
