Audio slideshow: Noctilucent clouds
Each summer, high in the night skies of the far northern and southern hemispheres a unique phenonmenon occurs - noctilucent clouds. Little is known about them, but now an amateur astronomer from north Wales is trying to predict when they are likely to appear.
Here, John Rowlands, one of four finalists in the BBC's search for the Amateur Scientist of the Year So You Want To Be A Scientist? - and his mentor, Professor Nick Mitchell from the University of Bath - take a closer look at these mysterious silver and blue waves at the edge of space.
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John Rowlands and Nick Mitchell were speaking to BBC Radio 4's Material World.
All images courtesy John Rowlands and Nick Mitchell. Music from Joni Mitchell and KPM Music.
Slideshow production by Paul Kerley. Publication date 19 July 2010.
Related links
Radio 4's So You Want To Be A Scientist
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