This image of electric blue noctilucent clouds was taken by astronaut Don Pettit while he was aboard the ISS.
Courtesy of Don Pettit and NASA TV
History of Observation of Noctilucent Clouds
Observations of noctilucent or "night-shining" clouds
were first reported in the summer of 1885. The reports were from northern Europe and Russia. In the late 1880’s, it was proposed that the clouds had a connection with the volcanic dust thrown into the Earth’s atmosphere by the powerful eruption of Krakatoa in Indonesia in 1883. This theory was later disproven. The first photos of these eerie clouds were taken in the late 1880’s.
In the early 1900’s, many scientists were trying to figure out what made up these clouds. Some proposed theories included that they were made of cosmic dust, water ice, or ice-covered cosmic dust. Knowledge about these clouds improved over the century and scientist Malzev proved that noctilucent clouds were not reliant on volcanic dust being present in the Earth's atmosphere. Systematic observations in Europe began around 1957 and the first rocket was launched into a noctilucent cloud in 1962. Also in 1962, systematic North American observations of noctilucent clouds began. Around the same time the first noctilucent clouds were observed from the Southern Hemisphere.
In the more recent past, further ground-based observations and space satellites such as the Orbiting Geophysical Observatory (OGO-6) satellite, the Solar Mesospheric Explorer (SME) satellite, and the HALOE (Halogen Occultation Experiment) confirmed that noctilucent clouds are primarily made of water ice. Their exact process of formation and any ties to global climate change will be investigated by the AIM satellite mission to be launched in 2006.
Crews aboard the International Space Station still routinely witness noctilucent clouds when flying over Australia and the tip of South America. Presently, you can participate as an observer of noctilucent clouds too and share that information with others on the Internet.
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