Noctilucent Clouds Display 2/7/13


Tremendous display of noctilucent clouds became visible last night and at about 1:00am were at their best.  Image taken with Canon 40D at 8 second exposure and ISO 160.



Noctilucent clouds are the highest clouds in Earth’s atmosphere, located in the mesosphere at altitudes of around 47 to 53 miles and are composed of tiny crystals of water ice up to 100 nm in diameter. They are normally too faint to be seen, and are visible only when illuminated by sunlight from below the horizon while the lower layers of the atmosphere are in the Earth’s shadow.

More details on noctilucent clouds can be found here