The second and final qualification motor (QM-2) test for the Space Launch System's booster, June 28, 2016, at Orbital ATK Propulsion Systems test facilities in Promontory, Utah. During the Space Launch System flight the boosters will provide more than 75 percent of the thrust needed to escape the gravitational pull of the Earth, the first step on NASA's Journey to Mars. (Photo by Bill Ingalls/NASA)

A machine works on a Rio 2016 Olympic medal at the Casa da Moeda do Brasil (Brazilian Mint) in Rio de Janeiro, Brazil, June 28, 2016. The Casa da Moeda do Brasil is the Brazilian mint, owned by the Brazilian government and administratively subordinated to the Ministry of Finances. It was established in 1694. (Photo by Sergio Moraes/Reuters)

Photochromes are vibrant and nuanced prints hand-coloured from black-and-white negatives. Created using a process pioneered in the 1880s, these images offer a fascinating insight into the world when colour photography was still in its infancy. A Tour of the World in Photochromes is at the Swiss Camera Museum, Vevey, until 21 August. Here: Street food in the Strada del Porto in Naples, Italy, 1899. (Photo by Swiss Camera Museum/The Guardian)

Sonam Kapoor, Jourdan Dunn and Lil' Kim attend the Ralph & Russo Haute Couture Fall/Winter 2016-2017 show as part of Paris Fashion Week on July 4, 2016 in Paris, France. (Photo by Samir Hussein/WireImage)

A string is used to ensure that the skirts of female members of the honour guard are in the same height from the ground as they prepare for a welcoming ceremony for Congo Republic President Denis Sassou Nguesso outside the Great Hall of the People in Beijing, China, July 5, 2016. (Photo by Jason Lee/Reuters)

A truck driver, butcher and firefighter are some of the subjects in the latest project by the photographer Chris Crisman. This series portrays women at work and focuses on occupations traditionally seen as male dominated. Here: Firefighter Mindy Gabriel, from Upper Arlington, Ohio. (Photo by Chris Crisman/The Guardian)

A storm trooper feeds a walker in the grass, taken in Glasgow, Scotland, December 2016. Tiny Storm Troopers and a mini Darth Vader are captured doing everyday activities – from taking a bath, to wrapping presents. Scottish Artist and Photographer, David Giliver created these scenes over a period of two years using toys and miniature props. (Photo by David Gilliver/Barcroft Images)

Santa Claus rides in his sleigh as he prepares for Christmas in the Arctic Circle near Rovaniemi, Finland December 15, 2016. At Santa Claus' Lapland home in Finland, his helpers sort out piles of letters from around the world, each detailing children's requests for this Christmas. (Photo by Pawel Kopczynski/Reuters)