Sentinel-1D: The Radar That Never Sleeps
The launch of ESA’s Sentinel‑1D satellite marks the completion of the first generation of the Sentinel‑1 constellation. Built by Airbus, this satellite carries a Synthetic Aperture Radar (SAR) designed to ensure uninterrupted global radar coverage for over seven years in orbit.
Sentinel‑1A, launched in 2014, is nearing the end of its operational life, while Sentinel‑1C successfully lifted off in December 2024. Together, they form a powerful radar network supporting observation of Earth’s land, seas, ice, and oceans as part of the European Copernicus programme.
Mission and Capabilities
Sentinel‑1D will continue the mission of its predecessors by conducting key monitoring activities and providing vital data for emergency response. The satellite’s radar instruments are central to observing environmental changes, detecting Earth’s dynamic processes, and supporting global climate studies.
“SAR instruments are an indispensable technology for Earth observation.”
Advantages of Synthetic Aperture Radar
Unlike optical satellites, which rely on reflected sunlight, radar satellites actively transmit and receive radio waves. This allows Sentinel‑1D to capture data regardless of weather or daylight conditions. Radar imaging penetrates clouds, fog, and rain, providing dependable observation around the clock.
SAR data reveals more than simple imagery—it detects changes in surface texture, such as the difference between rough seas and forest canopies, and can even penetrate vegetation layers, offering insights into otherwise hidden environmental features.
Summary
The Sentinel‑1D satellite extends ESA’s radar observation capability, delivering uninterrupted, all-weather monitoring that strengthens environmental and emergency operations across the globe.
Author’s summary: Sentinel‑1D completes ESA’s radar family, ensuring seven years of continuous all-weather Earth monitoring that enhances climate science and emergency response.