A sign advising to pray for rain hangs above an exhibit area at the 47th Annual World Ag Expo in Tulare, February 12, 2014. About a hundred years ago, when urban water systems were being developed throughout the state, the city of Sacramento wrote protections from metering into its charter, vowing that residents would always have the right to use as much water as they needed. But on Tuesday, the state's top water regulators released a framework for enforcing California's first statewide mandatory restrictions on urban water use – cuts of 25 percent for non-agricultural users ordered last week by Democratic Governor Jerry Brown as a devastating drought enters its fourth year. (Photo by David McNew/Reuters)

Paint splattered police officers look on during clashes outside Top Shop on Oxford Street, during marches in protest at government cuts on March 26, 2011 in London, England. Thousands are taking part in the Trades Union Congress (TUC) organised march to Hyde Park where a rally will take place. Police say they are deploying 4500 officers. (Photo by Dan Kitwood/Getty Images)

Hikaru Cho believes that we should challenge our imaginations to create new work using traditional tools, not fancy computers and software. (Photo by Jim Marks/PA Wire)

Vietnamese female traffic police officers march during a rehearsal for a military parade as part of the 40th anniversary of the fall of Saigon in southern Ho Chi Minh City (formerly Saigon City), Vietnam, on April 26, 2015. Vietnam marks the 40th anniversary of the fall of Saigon on April 30, the event that ended a war that lasted over 30 years, killing up to four million Vietnamese, the Vietnamese government said, and more than 58,000 U.S troops, the U.S. Department of Defense has said. (Photo by Reuters/Kham)

A protester clashes with a police officer in Athens' central Syntagma (Constitution) Square in this June 15, 2011 file photo. Greece triggered the regional financial crisis in 2009 when a far higher budget deficit than previously calculated emerged. The collapse of talks with creditors in Paris last November set off a month-long sequence of events leading to elections this week and proving Greece is still the region's weak link. The vote is expected to be won by Syriza, a far-left party opposed to the bailout, worrying investors and creditors alike. (Photo by Yannis Behrakis/Reuters)

A newly-hatched baby sea turtle makes its way into the Mediterranean Sea for the first time, as part of the Israeli Sea Turtle Rescue Center's conservation program, at a beach near Mikhmoret north of Tel Aviv, Israel September 9, 2019. Green turtles are endangered worldwide, the World Wildlife Fund says. Among other hazards, they are threatened by hunting, human encroachment on the beaches where they nest, and pollution of their feeding grounds offshore. According to the Israeli rescue center, only about 20 female green turtles nest along the Israeli Mediterranean coast during a breeding season that usually lasts from May until August. (Photo by Amir Cohen/Reuters)

Wanwisa, a Lao Yi Lai Heng Chinese opera performer waits backstage at the Plub Plachai temple on January 25, 2012 in Bangkok, Thailand. The traditional Chinese art form involving music, singing, martial arts and acting has a history of more than 500 years. There are about 30 members working with the group doing specials shows all week to celebrate the Chinese New year. The Chinese opera is popular in many parts of China, Malaysia, Singapore, Thailand and Macau. (Photo by Paula Bronstein/Getty Images)

ESA astronaut Tim Peake posted this stunning image on his social media channels, commenting: “Station passed through magnificent aurora Australis last night”. Tim is set to return to Earth on 18 June 2016, bringing his six-month Principia mission to the ISS to an end. During his stay he performed more than 30 scientific experiments for ESA and taking part in numerous others from ESA's international partners. ESA and the UK Space Agency have partnered to develop many exciting educational activities around the Principia mission, aimed at sparking the interest of young children in science and space. (Photo by Tim Peake/ESA/NASA)