SAGE3onISS

The Stratospheric Aerosol and Gas Experiment (SAGE) is a series of instruments designed by NASA to observe stratospheric ozone, aerosols, and water vapor from space. SAGE III is the newest and most advanced addition to the SAGE family.

NASA scientists sent the third generation of the instrument into space on February 19, 2017. Instead of flying on an un-manned satellite, SAGE III is mounted to the International Space Station (ISS) where it operates alongside experiments from all over the world in the space-based laboratory. It was robotically installed on the outside of the ISS and is now taking important measurements of gases and aerosols over 70% of the planet.

SAGE III takes measurements across the globe using a technique called occultation. Every time the sun, or moon, rises and sets, SAGE uses the light that passes through the atmosphere to measure gases and particles in that region of the atmosphere. From the ISS this happens over 30 times per day.