View Full Version : Noctilucent clouds and Krakatoa

26th Aug 2008, 04:49
Space station astronauts recently took pictures of these blue wispy clouds at the edge of earth's atmosphere. The fascinating bit to me was that they were never observed before Krakatoa erupted and sightings are now on the rise.

NASA - Strange Clouds at the Edge of Space (http://science.nasa.gov/headlines/y2008/25aug_nlc.htm?list99228)

People first noticed NLCs at the end of the 19th century after the 1883 eruption of Krakatoa. The Indonesian supervolcano hurled plumes of ash more than 50 km high in Earth's atmosphere. This produced spectacular sunsets and, for a while, turned twilight sky watching into a worldwide pastime. One evening in July 1885, Robert Leslie of Southampton, England, saw wispy blue filaments in the darkening sky. He published his observations in the journal Nature and is now credited with the discovery of noctilucent clouds.