Mysterious Glowing Cloud.

NASA will launch a new mission dubbed Aeronomy of Ice in the Mesosphere (AIM) to study a mysterious glowing cloud that has been spreading around the world:

The Aeronomy of Ice in the Mesosphere (AIM) mission will be the first satellite dedicated to studying this enigmatic phenomenon. Due to launch in late 2006, it should reveal whether the clouds are caused by global warming, as many scientists believe.

"Noctilucent" clouds, which glow at night, form in the upper atmosphere, at an altitude of about 80 kilometres, and their glow can be seen just after sunset or just before sunrise.

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