• The CALIPSO mission that analysed climate, weather, and air quality ended on August 1, National Aeronautics and Space Administration (NASA) announced recently.
• The CALIPSO (Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation) mission recorded more than 10 billion LIDAR measurements and helped create thousands of scientific reports over its 17 years of operation.
• It was launched jointly by NASA and France’s CNES (Centre National d’Etudes Spatiales), along with the cloud-profiling radar system on the CloudSat satellite.
• Working
  • The Lidar and radar instruments on the satellite direct beams of energy at Earth and measure how they reflect off the clouds and the aerosols in the atmosphere.
  • Other orbiting science experiments typically use passive sensors that measure the sunlight or other radiation reflected by the Earth or clouds.
• The two satellites were launched on April 28, 2006, and they circled the planet in a Sun-synchronous orbit from the North to the South poles.
  • This meant that they crossed the equator in the early afternoon every day.
  • They measured the altitude of clouds and layers of airborne particles like dust, sea salt, ash and soot while probing the “vertical structure” of the atmosphere.
• The observations from the two satellites allowed scientists to build more sophisticated models to understand complex atmospheric processes like cloud formation, atmospheric convection, precipitation and particle transport.

This was especially useful in situations like during the massive wildfires in Australia in 2020.