ESA astronaut Samantha Cristoforetti on the International Space Station 3 February 2015 during her Futura mission. Samantha is living and working on the Station as part of the Expedition 42 crew. Picture released on February 10, 2015. (Photo by ESA/NASA)

A mahout splashes water on his elephant in the river Sabarmati on a hot summer day in Ahmedabad, India, May 20, 2015. (Photo by Amit Dave/Reuters)

People watch as an acrobat rides his motorcycle around a circular track at an entertainment park set up outside a shrine in Rawalpindi, Pakistan, on June 19, 2013. (Photo by Muhammed Muheisen/Associated Press)

A Ka'apor Indian warrior (L) chases a logger who tried to escape after they captured him during a jungle expedition to search for and expel loggers from the Alto Turiacu Indian territory, near the Centro do Guilherme municipality in the northeast of Maranhao state in the Amazon basin, August 7, 2014. Tired of what they say is a lack of sufficient government assistance in keeping loggers off their land, the Ka'apor Indians, who along with four other tribes are the legal inhabitants and caretakers of the territory, have sent their warriors out to expel all loggers they find and set up monitoring camps in the areas that are being illegally exploited. (Photo by Lunae Parracho/Reuters)

Mahouts return home with their elephants carrying grass to feed them on the eve of the rhino census in Kaziranga National Park in Assam state, India, 24 March 2015. Kaziranga will be closed to visitors for the next two days for a census of the rhinos commencing 25 March, in a previous census in 2013 in the park the population of the Indian rhinos was 2329. (Photo by EPA/Stringer)

Two robotic legged squad support system (LS3) machines by the Defense Advanced Research Project Agency follow a technician during a demonstration at Joint Base Myer-Henderson Hall, Virginia, on September 10, 2012. (U.S. Marine Corps photo by Sgt. Mallory S. VanderSchans via The Atlantic)

UK Big Brother star Chloe Khan washes her Land Rover wearing a bikini and hot pants in Borehamwood, England on September 22, 2016. (Photo by Palace Lee)

People dressed as zombies participate in a parade for World Zombie Day 2016 in London's West End, Britain on October 9, 2016. (Photo by Splash News and Pictures)