A Mai-Mai rebel soldier shows off his guns at a checkpoint near the Mugunga refugee camp in Zaire; 1996. (Photo by Carol Guzy/The Washington Post)

In this photograph taken on July 10, 2012, a Pakistani worker pulls on a wire he will connect to a thick chain that will in turn be used to peel away a slab of the outer structure of a beached vessel in one of the 127 ship-breaking plots in Geddani, some 40Kms west of Karachi. (Photo by Roberto Schmidt/AFP Photo)

“The scientists behind NASA's $2.5 billion Curiosity rover mission on Mars on Tuesday explained the nature of a tiny, gleaming "flower" embedded in Red Planet rock, and revealed where they'll be using the SUV-sized robot's drill for the first time”. – Alan Boyle via NBCNews.com

Photo: Scientists say that a “Martian flower”, seen here in an image from the Curiosity rover's Mars Hand Lens Imager, is a 2-millimeter-wide grain or pebble that's embedded in the surrounding rock. Another, darker-colored mineral grain can be seen above and to the left. (Photo by NASA)

Neil Tuckett and Jamie Davidson, begin their attempt to drive a 1911 Model T Ford to the top of Ben Nevis on May 16,2011 in Fort William, Scotland. The challenge has been organised in memory of a pioneering Edinburgh car dealer Henry Alexander, who drove to the top of Ben Nevis to prove the ruggedness of the Model T. The original accent took five days with the route leading over boulders and through snow drifts. (Photo by Jeff J Mitchell/Getty Images)

New York Police Department tactical police officers stand guard near the New York Stock Exchange on September 9, 2011 in New York City. Officials are stepping up security in New York and Washington D.C. a day after U.S. officials received a credible but unconfirmed terror threat to utilize car bombs on bridges or tunnels in New York or Washington. (Photo by Justin Sullivan/Getty Images)

A gallery assistant holds a print of an Andy Warhol artwork estimated to fetch 1,500 GBP in Bonhams auction house on November 25, 2011 in London, England. The auction of prints of works ranging from old masters to contemporary artists takes place in London on November 29, 2011. (Photo by Oli Scarff/Getty Images)

(L-R) Mollie King and Frankie Sandford of The Saturdays performs for a dress rehearsal before the first night of their “All Fired Up!” tour at The Bournemouth International Centre on December 1, 2011 in Bournemouth, United Kingdom. (Photo by Dave J. Hogan/Getty Images)