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

Doctor Boaz Zissu of the Bar Ilan University shows the inscription on a 2,000-year-old ossuary at the Rockefeller Museum on June 30, 2011 in Jerusalem, Israel. The Israel Antiquities Authority have confirmed the credibility of the ancient ossuary, otherwise known as a stone chest in which to store bones, as bearing the name of a relative of the high priest Caiaphas from the New Testament. Laboratory tests have come back saying that the inscription with the name of “Miriam daughter of Yeshua son of Caiaphas, priest of Maaziah from Beth Imri” is both “genuine and ancient”. (Photo by Uriel Sinai/Getty Images)

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)

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)

Space shuttle Discovery sits atop NASA's 747 Shuttle Carrier Aircraft (SCA) ready to transport it from Kennedy Space Center to the Washington D.C., on April 17, 2012 in Cape Canaveral, Florida. Following the retirement of the shuttle fleet, Discovery will fly to Washington for display at the Smithsonian's National Air and Space Museum. (Photo by Lofty Ambitions)

A tattoo of Captain America drawn by artist Sean Karon on the leg of client Ron Raucci at the Hampton Roads Tattoo Festival in Virginia, on March 2, 2012. The tattoo was completed from start to finish in one five-and-a-half hour session and won the prestigious “tattoo of the day” contest. (Photo by Jason Reed/Reuters)