German radar satellite TerraSAR-X makes 100,000th orbit

Marking a major milestone that highlights almost two decades of continuous Earth observation, the German radar satellite TerraSAR-X completed its 100,000th orbit around Earth on 26 June this year. Since its launch in 2007, TerraSAR-X has delivered valuable insights into global environmental changes and supported a wide range of scientific and commercial applications.

Operating at an altitude of 514km, TerraSAR-X circles the globe in just under 95 minutes. In the past 18 years, the satellite has covered a total distance equivalent to a journey from Earth to Neptune and captured more than 350,000 high-resolution images using Synthetic Aperture Radar (SAR) technology, which allows for detailed imaging regardless of weather or daylight conditions.

Together with its twin satellite TanDEM-X, launched in 2010, TerraSAR-X also enables precise 3D mapping of Earth’s surface. Operated by the German Aerospace Center (DLR), the mission underscores Germany's leadership in space-based radar technology and its vital role in monitoring global change.

Backup units

Despite having surpassed its original six-year mission duration by nearly threefold, TerraSAR-X continues to deliver data with remarkable precision. This longevity is owed to several key factors: its critical components have proven to be exceptionally stable and accurate over time; essential systems are duplicated, allowing backup units to take over seamlessly in case of failure; and the onboard computer software can be updated directly from the ground.

With enough fuel reserves to remain operational for several more years, TerraSAR-X is expected to continue its vital work – barring major incidents such as severe solar storms or unexpected collisions with space debris. The satellite’s detailed images support a wide range of applications for the public sector, scientific research and commercial users worldwide. From informing political decisions to aiding disaster response, TerraSAR-X data plays a crucial role in shaping both immediate and long-term strategies for monitoring Earth’s dynamic changes.