Ada Wood, 10, perches on one of Castlerigg’s 38 stones during the summer solstice at Castlerigg stone circle in Cumbria, Britain, on June 21, 2016. (Photo by Christopher Thomond/The Guardian)

A person poses on the track during a fashion competition at the Durban July horse racing event in Durban, South Africa, July 2, 2016. (Photo by Rogan Ward/Reuters)

In this Wednesday, July 13, 2016, handout image provided by Solar Impulse, the Solar Impulse 2 flying over the pyramids, Egypt Cairo. The experimental solar-powered airplane has arrived in Egypt as part of its global voyage. (Photo by Jean Revillard, Rezo via the AP Photo)

Nepalese Hindu women pray to worship Lord Shiva during the first day of the Sarwan Brata festival, the month of fasting, at the premises of Pashupati Temple in Kathmandu, Nepal, 18 July 2016. Thousands of married and single Nepalese Hindu women will gather in temples for each Monday of the Sawan month (spanning from 16 July to 16 August) to pray for a long and prosperous life of their husbands or for a chance to find a good one. (Photo by Narendra Shrestha/EPA)

“An egg case or egg capsule, colloquially known as a mermaid's purse or devil's purse, is a casing that surrounds the fertilized eggs of some sharks, skates, and chimaeras”. – Wikipedia. Photo: OBX Skate (Raja eglanteria) Egg Case – Mermaid's Purse. (Photo by altereye1)

A model of a ghost made from translucent fibreglass is lit from inside at Gem's (Wax Models) Ltd, in the Portobello Road area of west London. The ghost is due to go to the Capistrano Mission Museum in California, where tourists are told the legend of how he frightened a young Indian girl novice to death. 1st May 1965. (Photo by Chris Ware/Keystone Features)

A man sleeps on a wheelbarrow outside a closed shop at a market during the first day of a ceasefire in Yemen's capital Sanaa April 11, 2016. (Photo by Khaled Abdullah/Reuters)

Internally displaced Syrian children play inside a refugee camp in the Hama countryside, Syria January 1, 2016. (Photo by Ammar Abdullah/Reuters)