A bear that wandered into a University of Colorado Boulder dorm complex falls from a tree after being tranquilized by Colorado wildlife officials on April 26, 2012. Colorado wildlife official Jennifer Churchill said that the 200-pound male bear was tagged and relocated to a remote Rocky Mountain area. The bear was hit by two cars on May 3 and died. (Photo by Andy Duann)

WOOTTON, UNITED KINGDOM - APRIL 07: Hot air balloons prepare to depart from Lydden Hill race circuit near Canterbury to take part in mass crossing of the Channel on April 7, 2011 in Wootton, England. 51 balloonists of various nationalities from across Europe took off from Kent making for Calais, France at about 7am. It is the first time a Guinness World Record bid has been made for "the largest group of hot air balloons to make the Channel crossing". (Photo by Oli Scarff/Getty Images)

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 walk under Australia's iconic landmark Harbour Bridge in Sydney on April 3, 2019, as heavy fog blankets the city. Low visibility due to heavy fog affected traffic in the city and caused flight delays at the Sydney airport. (Photo by Saeed Khan/AFP Photo)

Baylor head coach Kim Mulkey yells at her team during the second half of a women's Final Four NCAA college basketball semifinal tournament game against Oregon, Friday, April 5, 2019, in Tampa, Fla. (Photo by John Raoux/AP Photo)

Katie Boulter celebrates winning her match against Kazakhstan for Great Britain who went on to win the Federation Cup Tennis World Group II play-off at Copper Box Arena in London, England on April 21, 2019. (Photo by Shaun Brooks/Action Plus via Getty Images)

Beltane Fire Society performers celebrate the coming of summer by participating in the Beltane Fire Festival on Calton Hill April 30, 2019 in Edinburgh, Scotland. The event celebrates the ending of winter and is a revival of the ancient Celtic and Pagan festival of Beltane, the Gaelic name for the month of May. This years festival was highlighting climate change, with the central character The May Queen being seen to express her rage at the damage done to Earth. (Photo by Jeff J. Mitchell/Getty Images)

A family take a souvenir picture next to giant male panda Xiao Liwu, who was born at the San Diego Zoo and will be repatriated to China with his mother Bai Yun, bringing an end to a 23-year-long panda research program in San Diego, California, U.S., April 18, 2019. (Photo by Mike Blake/Reuters)