The Aeronomy of Ice in the Mesosphere (AIM) mission is the first satellite dedicated to the study of noctilucent clouds. Forming at altitudes above 50 miles, noctilucent clouds are so faint that they can only be seen from the ground in the reflected light of the Sun after it has set below the horizon. Since their discovery, their cause has been a subject of study as a possible indicator of climate change.
The Solar Occultation For Ice Experiment (SOFIE) instrument uses solar occultation to measure cloud particles, temperature and atmospheric gases involved in forming the noctilucent clouds studied by the Aeronomy of Ice in the Mesosphere (AIM) spacecraft. The instrument will reveal the recipe of chemicals that prompt formation of polar mesospheric clouds.
Because of their high altitude near the edge of space, noctilucent clouds shine at night when the Sun's rays hit them from below, while the lower atmosphere is bathed in darkness. These clouds typically form in the cold, summer polar mesosphere and are made of water ice crystals.
