The Prague astronomical clock, or Prague orloj, is a medieval astronomical clock located in Prague, the capital of the Czech Republic. The clock was first installed in 1410, making it the third-oldest astronomical clock in the world and the oldest one still working.

The Boeing 747-8 Intercontinental airliner, the company's newest and largest passenger plane, takes off for its first test flight at Paine Field Airport March 20, 2011 in Everett, Washington. The new plane features quieter, more fuel efficient engines, more seating and a redesigned interior.

Revelers dressed as Santa Claus drink outside at a bar during the annual SantaCon event December 10, 2011 in New York City. SantaCon is a mass gathering of revelers dressed as Santa Claus who take to the streets in cities across the country before Christmas. (Photo by Allison Joyce/Getty Images)

Israelis of Ethiopian origin take part in a rally against racism on January 10, 2012, in the southern Israeli town of Kiryat Malachi, Israel. Hundreds of demonstrators hit the streets of Kiryat Malachi, protesting what they call the discrimination of Ethiopian immigrants. According to Ethiopian residents of Kiryat Malachi, housing committees in the city have been refusing to sell them apartments. (Photo by Uriel Sinai/Getty Images)

Relatives of an earthquake victim are led away from ruins by a Policeman, on October 25, 2011 in Van, Turkey. Media are reporting more than 400 people have been killed in the 7.2 earthquake that struck in Eastern Turkey on October 23. The earthquake has left up to 40,000 people homeless in almost freezing conditions. (Photo by Ahmad Halabisaz/Getty Images)

Madison Sager (L), Jocelyn Sager and Susan Ihry (C) make their way through the West Acres Mall JCPenney store after 3 a.m. on November 25, 2011 in Fargo, North Dakota. The trio began shopping at 10 p.m. the night before at Walmart. (Photo by Chris Franz/Getty Images)