ESA’s Celeste broadcasts first navigation signal

On April, 8 ESA and industrial teams gathered at ESA’s Navigation Lab at ESTEC received the very first navigation signal from the Celeste mission.

This is a historic first in the world of European PNT. Sent from Celeste IOD-1, the signal is the first dual-frequency navigation message in the L- and S-band, the first sent from a European satellite in low-Earth orbit. A transmission from the Celeste IOD-2 satellite will follow in the coming days.

Navigation signals sent from low Earth orbit benefit from more strength, new dynamics and additional ranging geometry. This makes them valuable to complement existing medium Earth orbit systems and improve overall resilience, robustness, availability, and timeliness, especially in demanding environments like deep urban areas.

This first achievement comes as part of the satellites’ commissioning and in-orbit testing phase. Early April, days after their launch on March 28, the satellites completed their launch and early operations phase and were formally declared fit for life in orbit. The satellites are now ongoing checks to verify all vital subsystems, from propulsion to attitude and orbit control, are ready.

These signal transmissions are also contributing to bringing into use the required frequency filings in L- and S-bands for future operational European LEO-PNT missions, together with meeting other regulatory and compatibility commitments in accordance with International Telecommunication Union regulations.

www.esa.int