Challenger Deep Submersible is shown for the first time at the Virgin Group Media Announcement by the President & CEO of Virgin Airlines Sir Richard Branson at the Newport Harbor Yacht Club on April 5, 2011 in Balboa, California. (Photo by John M. Heller/Getty Images)

Actors Justin Timberlake (L) and Mila Kunis present an award onstage during the 2011 MTV Movie Awards at Universal Studios' Gibson Amphitheatre on June 5, 2011 in Universal City, California. (Photo by Kevin Winter/Getty Images)

A novice Bhutanese monk sleeps after hours of prayer waiting for class to be over at the Dechen Phodrang monastery October 18, 2011 in Thimphu, Bhutan. The monks average about 10 hours of study a day waking up at 5:00am. (Photo by Paula Bronstein/Getty Images)

Festive characters perform during Harrods 26th Annual Christmas Parade on November 5, in London, England. (Photo by Steve Finn/Harrods via Getty Images)

The Bratz Rock Angels are displayed at the Dream Toys 2005 Pre-Christmas Expo on October 5, 2005 in London. (Photo by Daniel Berehulak/Getty Images)

In this composite image (top) flooding is seen in the Toowoomba central business district on January 10, 2011 and (bottom) the same location as seen on January 5, 2012 in Toowoomba, Australia. January 10 marks the one year anniversary of the inland tsunami that devestated southern Queensland's Lockyer valley killing 23 people. (Photos by Dan Proud (top) and Lisa Maree Williams (bottom) /Getty Images)

“A dirty thunderstorm (also, Volcanic lightning) is a weather phenomenon that occurs when lightning is produced in a volcanic plume. Dirty thunderstorms have been reported in Chile above the Chaiten Volcano, above Alaska's Mount Augustine volcano, and Iceland's Eyjafjallajökull volcano”.

Photo: A cloud of ash pours from Puyehue volcano in southern Chile, at sunset on June 5, 2011. (Claudio Santana/AFP)