Iranians flash the victory sign from their car while celebrating on a street in northern Tehran, Iran, Thursday, April 2, 2015, after Iran's nuclear agreement with world powers in Lausanne, Switzerland. The United States, Iran and five other world powers on Thursday announced an understanding outlining limits on Iran's nuclear program so it cannot lead to atomic weapons, directing negotiators toward achieving a comprehensive agreement within three months. (Photo by Ebrahim Noroozi/AP Photo)

Dhofar Region, Oman. Much of Oman is desert, but the Arabian Sea coast in the Dhofar region represents a startling difference in climate. This coastal region catches the monsoon rains, or khareef, during the summer months. Drenching rains fall primarily on the mountainous ridge that separates the lush, fertile areas along the coast from the arid interior, recharging streams, waterfalls and springs that provide plentiful water supplies in the fertile lowlands for the remainder of the year. Image taken by Landsat 5 on April 2, 2005. (Photo by USGS/NASA)

A general view shows sculptures made of waste material titled “Trash People” by German Artist HA Schult (unseen), on April 2, 2014 in Ariel Sharon Park, in the suburbs of Tel Aviv. Hundreds of human-size figures constructed from 20 tons of recycled material, including iron, glass, computer parts, cans and more, will dominate the sky line of Tel-Aviv city and be placed in the park. (Photo by Jack Guez/AFP Photo)

Engineer Mikhail Venin works on an antenna for the Express AM8 new generation geostationary telecommunications heavy satellite at the large-sized transformed mechanical systems centre of the Reshetnev Information Satellite Systems company in the Siberian town of Zheleznogorsk April 2, 2014. The Express AM6 is a new generation satellite providing services including Russian governmental and presidential mobile communication, digital television and broadcasting, according to the Reshetnev company representatives. (Photo by Ilya Naymushin/Reuters)

A 2-year-old Florida panther is released into the wild by the Florida Fish and Wildlife Conservation Commission (FWC) on April 3, 2013 in West Palm Beach, Florida. The panther and its sister had been raised at the White Oak Conservation Center since they were 5 months old. The FWC rescued the two panthers as kittens in September 2011 in northern Collier County after their mother was found dead. The panther is healthy and has grown to a size that should prepare him for life in the wild. (Photo by Joe Raedle)

Venezuelan Hildemaro Ortiz relaxes inside of an abandoned bus in the border city of Pacaraima, Brazil on April 13, 2019. Ten destitute Venezuelan migrants who fled their country's crisis did not get far when they crossed into Brazil: they have been living for three months on an abandoned bus just across the border. (Photo by Pilar Olivares/Reuters)

Anti-frost candles burn in apricot plantations to protect flowering buds and blossoms from frost in the midst of the Swiss Alps, in Saxon, Canton of Valais, Switzerland, 05 April 2019. With an unusually low temperature forecast for the season, fruit growers try to protect their buds from frost damage with two different means, icy water or large candles. (Photo by Valentin Flauraud/EPA/EFE)

An Indian paramilitary soldier stands guard at a polling station during the second phase of India's general elections, in Srinagar, Indian controlled Kashmir, Thursday, April 18, 2019. Kashmiri separatist leaders who challenge India's sovereignty over the disputed region have called for a boycott of the vote. Most polling stations in Srinagar and Budgam areas of Kashmir looked deserted in the morning with more armed police, paramilitary soldiers and election staff present than voters. (Photo by Dar Yasin/AP Photo)