Mr. Grindell Matthews with his latest invention, the new photographic gun which is the latest development in sky signs. 1933. It can throw a beam of light 15 miles into the sky. (Photo by Fox Photos)

The phenomenon of the Hill of Crosses in northern Lithuania began when people started leaving crosses there hundreds of years ago – and continues to this day. These photos of a hill covered in crosses show the amazing sight it has become. Photo: In 1831 an unsuccessful uprising against the Russian czar left many rebels dead. Relatives of the dead rebels, with no bodies to bury, instead left crosses, according to the Daily Mail. (Photo by Richard Gardner/Rex USA)

Contestant Emilce Lezcano, center, prepares for the evening gown portion of the “Miss Gordita” beauty contest in Asuncion, Paraguay, Saturday, April 25, 2015. In their elegant evening gowns and elaborate hair styles, the contestants defy the conventional idea that only skinny women can be beautiful. (Photo by Jorge Saenz/AP Photo)

A tale of two foxes. Surprising behaviour, witnessed in Wapusk national park, on Hudson Bay, Canada, in early winter. Red foxes don’t actively hunt Arctic foxes, but where the ranges of two predators overlap, there can be conflict. Though the light was poor, the snow-covered tundra provided the backdrop for the moment that the red fox paused with the smaller fox in its mouth in a grim pose. (Photo by Don Gutoski/2015 Wildlife Photographer of the Year)

Baka pygmies in their forest home preparing food in, Sangha Forest, Central African Republic, February 2016. Here, in their forest home, traditional life continues in the face of multiplying challenges ranging from poachers, to ill health. Deep in the rainforests of central Africa lives one of the world’s most mysterious tribes. (Photo by Susan Schulman/Barcroft Images)

Sustainable development goal target 12.5 is to reduce waste. But with a planet increasingly dependent on technology, is that even possible? As of today, over 30m tonnes of electronic waste has been thrown out so far this year, according to the World Counts. Most e-waste is sent to landfills in Asia and Africa where it is recycled by hand, exposing the people who do it to environmental hazards. Kai Loeffelbein’s photographs of e-waste recycling in Guiyu, southern China show what happens to discarded computers. (Photo by Kai Loeffelbein/laif Agentur)

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)

HRP-4C, a five-foot humanoid robot developed at Japan's National Institute of Advanced Industrial Science and Technology, sings and dances with performers at the Digital Contents Expo in Tokyo on October 17, 2010. The robot runs entertainment software called Choreonoid, a name formed from the words “choreograph” and “humanoid”. (Yoshikazu Tsuno/AFP)