The Chernobyl disaster was a catastrophic nuclear accident that occurred on 26 April 1986 at the Chernobyl Nuclear Power Plant in Ukraine, which was under the direct jurisdiction of the central authorities of the Soviet Union. The Chernobyl disaster is the worst nuclear power plant accident in history in terms of cost and resulting deaths, and is one of only two classified as a level 7 event (the maximum classification) on the International Nuclear Event Scale (the other being the Fukushima Daiichi nuclear disaster in 2011). Photo: Graffiti of a crying baby on a wall, Chernobyl Power Plant, Chernobyl, Ukraine. (Photo by Hans Neleman/Getty Images)

In this handout GOES satellite image provided by the National Oceanic and Atmospheric Administration (NOAA), Irene reaches hurricane strength as it moves across Puerto Rico towards Hispaniola August 22, 2011 in the Caribbean Sea. Irene, the first hurricane of the Atlantic storm season, brought torrential rains and winds to Puerto Rico, downing trees and powerlines and flooding streets. The expected path will bring Irene through the Bahamas and is likely to hit Florida and up the east coast of the U.S. (Photo by NOAA via Getty Images)

A screen shows the new Automated Target Recognition software as a TSA employee, who couldn't provide her name, waits to walk into the advanced imaging technology unit to demostrate the new software that has been installed at Miami International Airport on August 23, 2011 in Miami, Florida. The new software is designed to enhance passenger privacy by eliminating passenger-specific images and instead auto-detecting potential threat items and indicating their location on a screen which shows a generic outline of a person. (Photo by Joe Raedle/Getty Images)

Patrick Boyle, The Earl of Glasgow and his son David, Viscount Kelburn pose at their home Kelburn Castle on August 30, 2011 in Largs, Scotland. The Earl of Glasgow has asked Historic Scotland if the graffiti can remain as a permanent feature of the Castle. The local council allowed the mural to be painted on the wall by Brazilian artists in 2007, with a three year limit put on the graffiti pending the start of rendering work at the castle.(Photo by Jeff J Mitchell/Getty Images)

Gengis “Lil Ceng” Ademoski (L) and Khaled “KC” Chaabi (R) of the four time world champion Berlin dance troupe “Flying Steps” strike a freeze on a piano played by muscian Jia Lim (C) of Singapore at the 17th century waterfront area of Nyhavn in build up to the Red Bull Flying Bach European Tour, a show that features the cultural clash of break dancing with the classical music of Johann Sebastian Bach, on August 30, 2011 in Copenhagen, Denmark. (Photo by Dean Treml/Red Bull via Getty Images)

A visitor tries out the new glass Skywalk at the top of the refurbished Blackpool Tower on September 1, 2011 in Blackpool, England. After a GBP Ј20 million refurbishment, the iconic seaside Blackpool Tower opened today to the general public. The observation deck at the top of the tower becomes the Blackpool Tower Eye and features a skywalk made of glass overlooking the sea and the promenade. The opening is part of Blackpool's GBP Ј250 million GBP regeneration project. (Photo by Christopher Furlong/Getty Images)

J. Schwartz (C) and Marianne Wittelsberger (2nd R) of Consumer Watchdog dress as members of the “Google Track Team” in a hallway of the Dirksen Senate Office Building prior to a hearing on Google September 21, 2011 on Capitol Hill in Washington, DC. Members of Consumer Watchdog attended the antitrust hearing dressed as the “Google Track Team” in white tracksuits emblazoned with Google's motto, “Don't be evil”, wearing “Wi-Spy” glasses and pretending to track unsuspecting people during the event. (Photo by Alex Wong/Getty Images)

The new Amazon tablet called the Kindle Fire is displayed on September 28, 2011 in New York City. The Fire, which will be priced at $199, is an expanded version of the company's Kindle e-reader that has 8GB of storage and WiFi. The Fire gives users access to streaming video, as well as e-books, apps and music, and has a Web browser. In addition to the Fire, Bezos introduced four new Kindles including a Kindle touch model. (Photo by Spencer Platt/Getty Images)