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)

These are the dunes of the Namib Desert, taken by Korea's Kompstat-2 satellite. The blue and white area is the dried riverbed of the Tsauchab river. (Photo by The European Space Agency)

Students pose for a pictures taken by their friends during spring break on the beach in the resort city of Cancun, Mexico, February 27, 2009. (Photo by Israel Leal/AP Photo)

“Eye of the Tower” by Mehmet Yasa; Verona, Italy. “The staircase and the bell looks like an eye. Architecture can fascinate us in many ways”. (Photo by Mehmet Yasa/Art of Building Photography Awards 2017)

A girl gets a helping hand across the road in Swansea, Wales, England on December 31, 2017. (Photo by Athena Picture Agency)

Moonlight illuminates sandstone buttes in the Valley of the Gods in the proposed Bear Ears National Monument near Mexican Hat, Utah, USA, 12 November 2016. In October 2015, a coalition of five Indian nations, including the Hopi, Ute, and Navajo, formally proposed the monument, attempting to preserve the parcel's 100,000 archeological sites from ongoing looting and grave robbing. Less than two months before handing over the White House to President Elect Trump, President Obama must decide if it's worth the political capital to designate Bear Ears a national monument. (Photo by Jim Lo Scalzo/EPA)

A couple covered with the US and the pride flags pay their tribute for the victims of a 12 June mass shooting in Orlando, Florida, USA, as they look at the Eiffel tower, illuminated in rainbow colours, in Paris, France, 13 June 2016. A total of 50 people including the suspect were killed and 53 were injured in a shooting attack at an LGBT club in Orlando, Florida, in the early hours of 12 June. The shooter was killed in an exchange of fire with the police after taking hostages at the club. (Photo by Yoan Valat/EPA)

A Boeing F/A-18 takes off to perform during the Farnborough International Airshow in Farnborough, Britain, 12 July 2016. The Farnborough International Air Show runs from 11-17 July. (Photo by Hannah Mckay/EPA)