Goats climb on students during a yoga class with eight students and five goats at Jenness Farm in Nottingham, New Hampshire, U.S. on May 18, 2017. Tucked away in a wooded corner of southern New Hampshire, Jenness Farm is the latest small U.S. agricultural operation to cash in on the social media-driven trend, in which yoga enthusiasts practice moves like the cat pose and bridge pose while goats climb around and sometimes on them. (Photo by Brian Snyder/Reuters)

A Chinese rescuer evacuates a young boy from flooded areas caused by heavy rains in Changsha city, central China's Hunan provincehangsha, capital of Hunan on July 3, 2017. (Photo by Imaginechina/Rex Features/Shutterstock)

A man dressed as a devil performs during a Krampus show in the southern Bohemian town of Kaplice, December 12, 2015. Each year people in traditional costumes and masks parade through the streets to perform an old ritual to disperse the ghosts of winter. (Photo by David W. Cerny/Reuters)

Girls practice sit-ups during gymnastics lessons at the Shanghai Yangpu Youth Amateur Athletic School in Shanghai, China, on May 4, 2016. China's sports system has been enormously successful since the country returned to the Olympic fold in 1980, culminating with the host nation topping the medals' table at the 2008 Beijing Olympics. And yet, with the Rio de Janeiro Games less than three months away, the system is beginning to break down due to the shifting demographics of a more prosperous nation. (Photo by Aly Song/Reuters)

Venezuela's food shortages, inflation and crumbling medical sector have become such a source of anguish that a growing number of young women are reluctantly opting for sterilizations rather than face the hardship of pregnancy and child-rearing. Traditional contraceptives like condoms or birth control pills have virtually vanished from store shelves, pushing women towards the hard-to-reverse surgery. While no recent national statistics on sterilizations are available, doctors and health workers say demand for the procedure is growing. (Photo by Carlos Garcia Rawlins/Reuters)

Yu Jietao, 26-year-old wood carver, sits in his homemade wooden car along a street in Guangfeng county of Shangrao, Jiangxi province, China February 9, 2015. The car can travel as fast as 30 km (18.6 miles) per hour, local media reported. (Photo by Reuters/Stringer)

Migrants scramble aboard a train at the station in Beli Manastir, Croatia September 18, 2015. Migrant numbers in Europe will build up in coming days and their flows may fragment further into new routes, the U.N. refugee agency said on Friday, urging the European Union to grasp a last chance to resolve the refugee crisis next week. (Photo by Laszlo Balogh/Reuters)

The competition is run by Royal Observatory Greenwich sponsored by Insight Investment and in association with BBC Sky at Night Magazine. This year astrophotographers from 91 countries sent in more than 4,200 spectacular entries. Here: The Milky Way rises above an isolated lighthouse in Tasmania. Shot by James Stone of Australia. (Photo by James Stone/Astronomy Photographer of the Year 2018)