Two ancient bronze coins, which according to Israel Antiquities Authority archaeologists were struck by the Roman procurator of Judea, Valerius Gratus, in the year 17/18 CE and recently were revealed in excavations beneath the Western Wall in Jerusalem's Old City are exposed to the media' on November 23, 2011 in Israel. (Photo by Lior Mizrahi/Getty Images)

An iCub robot built by the Italian Institute of Technology tracks a ball in the Robotville exhibition at the Science Museum on November 29, 2011 in London, England. The Science Museum's Robotville exhibition showcases 20 unique and cutting-edge robots from European research laboratories, it is free to enter and runs from December 1–4, 2011. (Photo by Oli Scarff/Getty Images)

Police officers carry an opposition activist, who was detained while taking part in an unauthorized rally, at the Triumfalnaya Square in central Moscow, late on December 6, 2011.

Photo by: Sergey Muhamedov; Source: LiveJournal

A Shi'ite worshiper bleeds after cutting his scalp in a ritual display of mourning during an Ashura commemoration ceremony outside Kadhimiya shrine on December 6, 2011 in Baghdad, Iraq. Ashura marks the death of Prophet Muhammad's grandson the revered Imam Hussein in Karbala, Iraq in 680 AD. Shi'ite festivals were prohibited during the time of Sunni dictator Saddam Hussein's rule. (Photo by Mario Tama/Getty Images)

NASA space shuttle Atlantis is prepared on the Vehicle Assembly Building floor at the Kennedy Space Center May 18, 2011 in Cape Canaveral, Florida. The space shuttle program ends with Atlantis mission STS-135 scheduled for early July. Space shuttle Atlantis will carry the Raffaello multipurpose logistics module to deliver supplies, logistics and spare parts to the International Space Station. Atlantis also will fly a system to investigate the potential for robotically refueling existing spacecraft and return a failed ammonia pump module. (Photo by Roberto Gonzalez/Getty Images)

Ucil, a trained monkey, takes part in a street performance on June 1, 2011 in Jakarta, Indonesia. The street performances usually involve the monkeys wearing masks, such as dolls' heads or attire to mimic humans, with the monkeys trained to act out human activities such as shopping, riding bicycles or other simulations of human behaviour. Poverty drives the handlers to exploit the monkeys in the hope of earning small change, but the effect and cruelty to the monkeys is a cause that charities such as the Jakarta Animal Aid Network are increasingly taking up. (Photo by Ulet Ifansasti/Getty Images)

Music fans arrive in the mud and the rain at the Glastonbury Festival site at Worthy Farm, Pilton on June 22, 2011 in Glastonbury, England. Heavy rain and mud greeted music fans as the gates to the five-day festival opened to the public this morning. This year the festival will feature headline acts U2, Coldplay and Beyonce. The festival, which started in 1970 when several hundred hippies paid 1 GBP to watch Marc Bolan, has grown into Europe's largest music festival attracting more than 175,000 people over five days. (Photo by Matt Cardy/Getty Images)

Vladislav Doronin and Naomi Campbell attend the religious ceremony of the Royal Wedding of Prince Albert II of Monaco to Princess Charlene of Monaco in the main courtyard at the Prince's Palace on July 2, 2011 in Monaco. The Roman-Catholic ceremony follows the civil wedding which was held in the Throne Room of the Prince's Palace of Monaco on July 1. With her marriage to the head of state of the Principality of Monaco, Charlene Wittstock has become Princess consort of Monaco and gains the title, Princess Charlene of Monaco. Celebrations including concerts and firework displays are being held across several days, attended by a guest list of global celebrities and heads of state. (Photo by Sean Gallup/Getty Images)