Two men standing on a high catwalk, surveying the construction of the Brooklyn Bridge, with Manhattan in the background, New York City, 1877. (Photo by Museum of the City of New York/Archive Photos/Getty Images)

Dotty, a short-haired pointer belonging to Simon Kirby MP, devours a Parliament shaped cake watched by a jack russell Maximus (L) owned by Matthew Offord MP during the Westminster Dog of The Year competition in Victoria Tower Gardens on October 13, 2011 in London, England. The annual competition was won by Conservative MP for Tiiverton and Honiton Neil Parish with his Labrador Wilberforce, who was among the 15 Conservative MPs to enter versus only two Labour MP entrants. (Photo by Peter Macdiarmid/Getty Images)

The moon rises behind Reunion Tower in downtown Dallas, Sunday evening, November 13, 2016. On Monday the supermoon will be the closest full moon to earth since 1948, and it won't be as close again until 2034. (Photo by Tom Fox/The Dallas Morning News via AP Photo)

A small section of the expanding remains of the Veil Nebula, a massive star that exploded about 8,000 years ago. The entire nebula is 110 light-years across, covering six full moons on the sky as seen from Earth, and resides about 2,100 light-years away in the constellation Cygnus, the Swan. Image taken by NASA's Hubble Space Telescope. Released September 24, 2015. (Photo by Reuters/NASA/ESA/Hubble Heritage Team)

A participant runs towards the waters of the North Sea during the annual New Year's plunge event in Ostend, Belgium, January 2, 2016. (Photo by Francois Lenoir/Reuters)

Rwandan refugees cross the Rusumo border to Tanzania from Rwanda carrying their belongings, goats, mattresses and cows, May 30, 1994. The bloodshed that claimed 800,000 Tutsi and moderate Hutu lives began 25 years ago on April 7, 1994, when a plane carrying Rwandan President Juvenal Habyarimana, Burundi President Cyprien Ntaryamira and a French air crew was shot down. (Photo by Jeremiah Kamau/Reuters)

Aurora Australis from Beerbarrel Beach, by James Stone. Runner Up: Aurorae. (Photo by James Stone/Astronomy Photographer of the Year)