In this handout image provided by NASA, the space shuttle Endeavour is seen on launch pad 39a as a storm passes by prior to the rollback of the Rotating Service Structure (RSS) April 28, 2011, at Kennedy Space Center in Cape Canaveral, Florida. During the 14-day mission, Endeavour and the STS-134 crew will deliver the Alpha Magnetic Spectrometer (AMS) and spare parts, including two S-band communications antennas, a high-pressure gas tank and additional spare parts for Dextre. Launch is targeted for April 29 at 3:47 p.m. EDT.

People take photographs of waves crashing against the harbour wall on January 3, 2012 in Porthcawl, Wales. (Photo by Matt Cardy/Getty Images)

Soldiers pose for a photo during the flower exhibition marking the 105th birth anniversary of the country's founding father, Kim Il Sung in Pyongyang, North Korea April 16, 2017. (Photo by Damir Sagolj/Reuters)

An anti-government protester wearing a Guy Fawkes mask stands with a shield near flames from molotov cocktails thrown at a water cannon by anti-government protesters during riots in Caracas in this April 20, 2014 file photo. (Photo by Jorge Silva/Reuters)

A fireball erupts from a 16-inch gun on the battleship USS Wisconsin during a live fire exercise in the Persian Gulf, October 13, 1990. The ship is in the Gulf as part of Operation Desert Shield. (Photo by John Gaps III/AP Photo)

A blurred panaroma of Roemerberg historic center is reflected in a soap bubble in Frankfurt am Main, Germany, 09 July 2015. (Photo by Frank Rumpenhorst/EPA)

Lightning strikes near Jacobsdorf at the Oder-Spree district in eastern Germany, September 1, 2015. (Photo by Patrick Pleul/AFP Photo)

A humanoid robot named “Robi” sits during a promotional event for the launch of a weekly Robi Magazine in Tokyo, Japan, 20 January 2015. Created by roboticist Tomotaka Takahashi, the 34-centimeter tall humanoid robot can recognize and respond to more than 200 words and phrases, walk and dance. Parts of the robot will be put on sale in a weekly magazine to be fully assembled with 70 issues. (Photo by Franck Robichon/EPA)