What is Earth Observation?

Earth Observation (EO) refers to the use of remote sensing technologies to monitor land, marine (seas, rivers, lakes) and atmosphere. Satellite-based EO relies on the use of satellite-mounted payloads to gather imaging data about the Earth’s characteristics. The images are then processed and analysed in order to extract different types of information that can serve a very wide range of applications and industries.

EO technologies utilize different types of sensors on their payloads:

  • Optical or thermal sensors are payloads monitoring the energy received from the Earth due to the reflection and re-emission of the Sun’s energy by the Earth’s surface or atmosphere. They operate between the visible and infrared wavelengths of the electromagnetic spectrum.
  • Radar sensors are payloads operating in the lower part of the spectrum (longer wavelengths). Most of these sensors send energy to Earth and monitor the energy received back from the Earth’s surface or atmosphere, enabling day and night monitoring during all weather conditions. 

The European Union's Earth observation programme is Copernicus. It consists of a complex set of systems that collect data from multiple sources: Earth observation satellites and in-situ sensors such as ground stations, and airborne and sea-borne sensors. This data is processed to provide users with a set of services based on reliable and up-to-date information. Examples include monitoring the state and evolution of our environment, on land, at sea and in the air, and the ability to rapidly assess situations during crises such as extreme weather events or during conflict situations.

Updated: May 17, 2021