Convicted murderer Hector Alvarado Mazariegos, right, drops to the ground as he is hit by bullets of a Guatemala firing squad in the public cemetery at Mazatenango, June 28, 1975. His companion, Rocael Ortiz, met the same fate a few seconds later. Both were convicted of murder. (Photo by AP Photo/Anzueto)

The 33rd All Women Lifeguard Tournament held at Sandy Hook Gateway National Recreation Area in Sandy Hook New Jersey. Wednesday, July 26th, 2017 (Photo by Anthony Causi)

A bonnet macaque sits on consecrated idols of snakes as it drinks milk offered by a devotee during the Hindu festival of Nag Panchami, which is celebrated by worshipping snakes to honour the serpent god, inside a temple on the outskirts of Bengaluru, India, July 27, 2017. (Photo by Abhishek N. Chinnappa/Reuters)

A general view of atmosphere at the annual VOLT Festival in Sopron, 208 kms west of Budapest, Hungary on August 16, 2016. (Photo by Rockstar Photographers)

Jo-Anne McArthur’s book of photographs puts the spotlight on ethics of zoos around the world. Accompanied by essays by Born Free Foundation’s Virginia McKenna and philosopher Lori Gruen, the images and stories are also shared online through “A Year of Captivity”. Here: Asian Elephant, Denmark, 2016. (Photo by Jo-Anne McArthur/Born Free Foundation/The Guardian)

People walk on the street in Samara, Russia on July 18, 2017. (Photo by David Mdzinarishvili/Reuters)

A model presents a creation by Colombian brand Elena Plus Clothing at Colombiamoda during Medellin's fashion week in Itagui municipality near Medellin, Antioquia department, Colombia, on July 24, 2017. Colombiamoda will take place between the 24th and 27th of July. (Photo by Joaquin Sarmiento/AFP Photo)

“Mr Big Dipper”, Nicholas Roemmelt (Denmark). A stargazer observes the constellation of the Big Dipper perfectly aligned with the window of the entrance to a large glacier cave in Engadin, Switzerland. This is a panorama of two pictures, and each is a stack of another two pictures: one for the stars and another one for the foreground, but with no composing or time blending. (Photo by Nicholas Roemmelt/National Maritime Museum/The Guardian)