Solar radiation enters the Earth's atmosphere with a portion being scattered by clouds and aerosols.

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at the NASA Langley Research Center

SAGE III-ISS Occultation Event

SAGE III-ISS Occultation Event

SAGE III-ISS Occultation Event
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This moonset image is illustrating an occultation event from the SAGE III instrument, which is used to measure Ozone, NO2 and NO3 concentrations in the upper atmosphere. Nitrogen Trioxide (NO3) virtually disappears from the atmosphere when the sun rises, but SAGE III/ISS utilizes lunar occultation to measure its concentration.

Tool to predict future occultation events -


The SAGE III-ISS mission is a joint research experiment between NASA, the European Space Agency (ESA), Thales Alenia Space-Italia (TAS-I), Ball Aerospace & Technologies Corp. (BATC), and Hampton University. Launched Feb. 19, 2017, the Stratospheric Aerosol and Gas Experiment III on the International Space Station (SAGE III/ISS) is used to study profiles of aerosols and gases. Occultation is a technique which involves looking at the light from the sun or moon as it passes through Earth’s atmosphere at the edge, or limb, of the planet.


Explore SAGE III-ISS Data and Information
Read the latest SAGE III-ISS Version 5.1 Data Release Announcement
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