A military band prepares to play the national anthems before Cuban President Raul Castro welcomes U.S. President Barack Obama at the Palacio de la Revolucion in Havana March 21, 2016. Barack Obama on Sunday became the first US president in 88 years to visit Cuba, touching down in Havana for a landmark trip aimed at ending decades of Cold War animosity. (Photo by Jonathan Ernst/Reuters)

In this image distributed on Tuesday, September 29, 2015, 11-year old dance star Taylor Hatala and friends are seen filming their new Monster High Boo York, Boo York music video #CityGhouls in Los Angeles. (Photo by Casey Rodgers/Invision for Mattel/AP Images)

A boy and a woman run across a railway track as a train approaches in Chengdu, Sichuan province, China, October 8, 2015. Many residents disregard sign prohibiting this kind of illegal crossing and choose to do so to save time, local media reported. (Photo by Hao Fei/Reuters/Western China Metropolis Daily)

A Kenyan soldier takes cover as shots are fired in front of Garissa University in Garissa town, located near the border with Somalia, some 370km northeast of the capital Nairobi, Kenya, 02 April 2015. At least 15 people have been killed and some 60 were injured in an attack carried out by Somalia's Islamist militant group al-Shabab, according to local media reports. (Photo by Dai Kurokawa/EPA)

A penguin swims in its enclosure during a photocall to promote London Zoo's annual stock take of animals on January 4, 2012 in London, England. The zoo's stocktake takes place annually, and gives keepers a chance to check on the numbers of every one of the animals from stick insects and frogs to tigers and camels. (Photo by Dan Kitwood/Getty Images)

A polar bear whose bottom half is caked in oily black gunk. A whale wrapped in striped fabric: a pseudo straightjacket. These are the messes climate change leaves behind, the things we know are happening but often don’t have the opportunity to see with our own eyes. Swiss street art duo Christian Rebecchi and Pablo Togni, otherwise known as NeverCrew, met in art school when they were 15 and started making work together soon after. As a team, the artists adorn the world with eye-popping and gut-wrenching images depicting the consequences of humanity’s actions on earth. (Photo by NeverCrew/The Huffington Post)

Samba dancers perform during the annual Asakusa Samba Carnival in Tokyo, Japan August 27, 2016. Asakusa is a district in Taitō, Tokyo. The neighborhood is famous for its annual Brazilian style carnival. There is a significant Brazilian presence in the local community and the Association of Samba Schools of Asakusa is based there. (Photo by Kim Kyung-Hoon/Reuters)

Virgin Galactic's new spaceship N202VG (bottom L) is seen behind the WhiteKnightTwo carrier aircraft mothership (front), which landed safely after splitting from SpaceShipTwo, in a hangar at Mojave Air and Space Port in Mojave, California, November 4, 2014. (Photo by Lucy Nicholson/Reuters)