Students pose for a pictures taken by their friends during spring break on the beach in the resort city of Cancun, Mexico, February 27, 2009. (Photo by Israel Leal/AP Photo)

Google's vice president Alan Eustace looks out of his spacesuit into the stratosphere prior to a record-breaking skydive over New Mexico, in this still image taken from video October 24, 2014, a handout courtesy of the Paragon Space Development Corporation. Eustace was lifted up 135,890 ft (41,420 metres) by an enormous balloon while wearing a specially designed pressurized space suit, the Paragon Space Development Corporation said. Eustace remained in a free fall for approximately 4.5 minutes before landing safely nearly 70 miles (43.4 kms) from his launch point, setting a world record for the highest skydive and breaking the sound barrier in the process. Eustace landed safely on the ground just 15 minutes after he was lifted into the air. (Photo by Reuters/Paragon Space Development Corporation)

China’s new tallest building has received unexpected publicity thanks to Russian free climbers Vadim Makhorov and Vitaly Raskalov. The pair took two hours to climb 650 metres up the unfinished Shanghai Tower. They did not use safety equipment on their ascent to the top of a crane attached to the tower, from where they took these extraordinary pictures of Shanghai. Photo: Vitaly Raskalov's feet dangle from the top of the Shanghai Tower, high above the Shanghai World Financial Centre. (Photo by Vitaly Raskalov/Caters News Agency)

Four-man bicycle is powered by five chains and has brakes on both its wheels, 1948. The bike was built by Art Rothschild (top position) who broke three ribs while learning how to ride it. (Photo by Wallace Kirkland/Time & Life Pictures)

Injured horses huddle together in Oklahoma City on Monday. (Photo by Chris Landsberger/The Oklahoman)

A tourist poses for a picture with the Sphinx at the Pyramids of Giza in Cairo, Egypt, on October 19, 2011. (Reuters/Jamal Saidi)

China has sent its first woman into space on a mission to dock with an orbiting station, the latest step in an ambitious programme to go to the moon and on to Mars.

Photo: China's first female astronaut Liu Yang, waves during a sending off ceremony before she departs for the Shenzhou 9 spacecraft rocket launch pad at the Jiuquan Satellite Launch Center in Jiuquan, China, Saturday, June 16, 2012. China will send its first woman and two other astronauts into space Saturday to work on a temporary space station for about a week, in a key step toward becoming only the third nation to set up a permanent base in orbit. (Photo by Ng Han Guan/AP Photo)

Two traditional folk dancers performing in Teheran, Iran. (Photo by Keystone Features/Getty Images). 25th January 1961