A Sudanese man walks to a United Nations displacement camp after crossing into Tunisia from Libya on March 06, 2011 in Ras Jdir, Tunisia. As fighting continues in and around the Libyan capital of Tripoli, tens of thousands of guest workers from Egypt, Tunisia, Bangladesh and other countries are fleeing to the border of Tunisia to escape the violence. The situation has turned into a humanitarian emergency as fledgling Tunisia is overwhelmed with the workers. Libyan leader Muammar Gaddafi has vowed to fight to the end. (Photo by Spencer Platt/Getty Images). RAS JDIR, TUNISIA – MARCH 06 2011

A Geminid meteor streaks diagonally across the sky against a field of star trails behind one of the peaks of the Seven Sisters rock formation in this long exposure early December 14, 2007 in the Valley of Fire State Park in Nevada. The meteor display, known as the Geminid meteor shower because it appears to radiate from near the star Castor in the constellation Gemini, is thought to be the result of debris cast off from an asteroid-like object called 3200 Phaethon. The shower is visible every December. (Photo by Ethan Miller/Getty Images)

Sudanese refugees living in Tel Aviv dance as they celebrate independence from the Republic of Sudan on July 10, 2011 in Tel Aviv, Israel. Israel's Prime Minister Benjamin Netanyahu announced that Israel recognizes the Republic of South Sudan as independent state. South Sudan became a state on July 9 after it separated from the north, with its capital in Juba, following a vote for independence. The country was recognized on July 8 by the government of Sudan. (Photo by Uriel Sinai/Getty Images)

The first load of passengers queuing for the Bennie Railplane in Glasgow; the inventor George Bennie is third in the queue. The streamlined cars are self propelled, driven by air screws in front and behind, and hang from a steel girder. (Photo by J. A. Hampton/Topical Press Agency/Getty Images). 4th July 1930

An Iranian soldier guards two German tourists near the Iranian-Turkish border during World War II. Since the British occupation of Iran, all Axis nationals are being expelled from the country. (Photo by Three Lions/Getty Images). Circa 1941

Members of Germany's elite police unit, the Spezialeinsatzkommando, or SEK, demonstrate an abseil deployment from a helicopter during a media event on March 20, 2012 in Minden, Germany. The SEK is the special response team of Germany's state police force and typically deploys in high-risk situations, such as bank robberies, hostage takings and the arrest of armed and dangerous fugitives. (Photo by Thomas Starke/Getty Images)

Armed Karo herdsman just back from protecting their cattle herds come down to the river to wash decorative clay markings off their bodies at the end of the day in the Omo Valley, South West Ethiopia. Dus, Omo Valley, Ethiopia, January 2008. (Photo by Brent Stirton/Discovery Communications)