Celeste: Countdown to Launch 1
The European Space Agency is preparing to launch the first two satellites of its Celeste low Earth orbit positioning, navigation and timing demonstration mission from Rocket Lab’s Launch Complex 1 on the Māhia Peninsula in New Zealand, with liftoff scheduled on 25 March 2026 aboard a Rocket Lab Electron rocket. The mission will deploy a pair of demonstrator spacecraft into roughly 510 km altitude orbit to begin in‑orbit testing of navigation signal technologies designed to complement and enhance existing medium Earth orbit systems such as Galileo and EGNOS. ESA officials have produced a “Countdown to Launch 1” video outlining launch preparations, spacecraft integration and mission objectives in advance of the flight.
The two Celeste demonstrator satellites consist of a 12‑unit and a 16‑unit CubeSat built by European industrial teams led by GMV in Spain and Thales Alenia Space in France, respectively, and they carry navigation payloads that will transmit representative signals in L‑ and S‑frequency bands following deployment. These first spacecraft are part of the mission’s in‑orbit demonstration phase, intended to validate low Earth orbit signal strength, autonomous orbit determination and multi‑band timing performance in compliance with International Telecommunication Union frequency filings. A broader deployment of additional satellites currently under development is planned through 2027 to expand the constellation and test further capabilities.
Celeste represents Europe’s first effort to demonstrate a navigation layer operating closer to Earth than traditional GNSS constellations, aiming to improve resilience and service availability in urban, high‑latitude and indoor environments by complementing Galileo’s medium orbit coverage. The mission supports ESA’s FutureNAV programme and contributes to a future operational satellite navigation architecture that could integrate low Earth orbit layers with existing space‑based systems, advancing technical maturity and regulatory compliance ahead of industrialisation phases beyond the demonstrator campaign.
