Observations of noctilucent clouds from a stratospheric balloon

The experimental campaign Stratospheric Observations of Noctilucent Clouds (SONC) was conducted on the night of 5-6 July 2018 with the aim of photographing noctilucent clouds (NLC) and studying their large-scale spatial dynamics at scales of 100-1600 kilometres. Noctilucent clouds form as ice particles in the summer mesosphere at heights of 80-85 kilometres, and exhibit large wave structures. Atmospheric scientists at the Swedish Institute of Space Physics (IRF) study these waves and the formation processes of the clouds.

An automated high-resolution camera (equipped with a wide-angle lens) was lifted by a sounding balloon to 21 km altitude above the Moscow region in Russia, taking several hundreds of NLC images during the flight.

By using images from a balloon-borne camera, we hope to better understand large-scale wave processes at the summer mesopause such as gravity waves, planetary waves and solar tides," says Peter Dalin, scientist at IRF in Kiruna.

The NLC camera was stabilized using a 3-axis motorized gimbal stabilized platform designed and built by the Moscow Aerospace Laboratory (nearspace.ru). This is the first time such a balloon-borne observation of NLC from the stratosphere has been conducted, making it possible to register and image NLC at large distances. The flight data are at present being analysed.