Gas-masked men of the British Machine Gun Corps with a Vickers machine gun during the first battle of the Somme, 1916. (Photo by General Photographic Agency/Getty Images)

A participants mends his vintage car during the annual London to Brighton veteran car run in London, Britain November 6, 2016. Around 600 classic cars took part in the annual 60 mile journey to the south coast resort. (Photo by Neil Hall/Reuters)

Couple getting intimate on couch. (Photo by Vincent Besnault/Getty Images)

The Pink Floyd inflatable pig floats next to Broadcasting House to promote their new exhibition at the V&A museum, in London, Britain May 10, 2017. (Photo by Neil Hall/Reuters)

Astronaut Donald R. Pettit would often rig an array of as many as six cameras in the cupola windows and set them all to fire continuously for events such as sunsets, which only last around seven seconds on the ISS. (Photo by Donald R. Pettit)

An Afghan girl makes a pile of unbaked bricks near the road passing through the Shamali Plains, about 10 kilometers (6 miles), west of Bagram, Afghanistan, Wednesay April 9, 2003. Children assist parents in their job to supplement family income. (Photo by Gurinder Osan/AP Photo)

In this photo taken on Friday, July 14, 2017, a student at a paramilitary camp for children calls the rank to attention outside Kiev, Ukraine. As the deadly conflict in eastern Ukraine entered its third year, some parents in Ukraine are anxious to make sure their children are ready to fight it, instead of swimming and playing volleyball. (Photo by Efrem Lukatsky/AP Photo)

Eleonora Brunacci and Mariano Di Vaio walk the red carpet ahead of the “Racer And The Jailbird (Le Fidele)” screening during the 74th Venice Film Festival at Sala Grande on September 8, 2017 in Venice, Italy. (Photo by Pascal Le Segretain/Getty Images)