In a July 14, 1967 file photo, left, National Guardsmen make their way along Market Street in Newark, N.J, after an evening of deadly rioting and looting in what came to be known as the Newark riots. In a June 16, 2017 photo, right, an ambulance drives on the same block 50 years later. (Photo by AP Photo/File, left; Julio Cortez, right)

A tattoo is displayed on the arm of a girl during Bandung Body Art Festival at in Bandung, West Java, on December 7, 2014. Upon its establishment in 2010, founders of the Bandung Body Art Festival sought to celebrate an art form that was once taboo and associated with criminals. Tattoos are now an increasingly acceptable part of Indonesia’s urban landscape, and the annual event this year continued its campaign with 45 tattoo artists offering their services for free at the Ganesha Cultural Center. (Photo by Rezza Estily/JG Photo)

In this photo taken on July 19, 2014, a man looks at an excavation as an A.R.M.H., Association for the Recovery of Historical Memory, volunteer digs on the search for the body of Perfecto de Dios, in a hidden grave in Chaherrero, Spain. Across Spain, volunteer teams of archeologists, anthropologists and forensic scientists head out every year on expeditions to dig for suspected mass graves – a legacy of Spain's fascist past during the time of General Francisco Franco. (Photo by Daniel Ochoa de Olza/AP Photo)

Image of the Clouds taken in August 2014 by astronauts on board the International Space Station (ISS). A year from space photographs of hurricanes, typhoons and meteorite craters show an astronauts-eye view of our planet from hundreds of miles above the earth. The illuminating images were taken by astronauts onboard the International Space Station (ISS) over the course of 2014. (Photo by NASA/SPL/Barcroft Media)

Revelers dance during the “Ceu na Terra”, or Heaven on earth, carnival parade in Rio de Janeiro, Brazil, Saturday, February 7, 2015. Rio's over-the-top Carnival is the highlight of the year for many local residents. Hundreds of thousands of merrymakers are beginning to take to the streets in open-air “blocos” parties. (Photo by Felipe Dana/AP Photo)

Boys play basketball in the facilities of Belarus' Republican Clinic of Speleotherapy within a salt mine, as part of their treatment, near the town of Soligorsk, south of Minsk, February 19, 2015. According to the state clinic, more than 7,000 children and adults seek medical treatment for respiratory illness each year in the subsurface chambers of its facilities, located 420 metres underground between layers of potassium and stone salts in an operational salt mine. (Photo by Vasily Fedosenko/Reuters)

A handout image released by the Taronga Zoo shows Veiled Chameleon hatchlings at Taronga Zoo in Sydney, Australia, 11 March 2015. Taronga has welcomed more than 20 baby chameleons, with the last of three clutches of eggs hatching this week. Veiled Chameleons, or Chamaeleo calyptratus, are native to Saudi Arabia and Yemen and can live up to five years. (Photo by EPA/Taronga Zoo)

In this February 2, 2015 photo, tourists jump as they pose for a picture, after disembarking from the Ocean Nova cruise ship, on King George Island, Antarctica. This tourist season, which runs November through March, more than 37,000 visitors are expected to walk on the coldest continent on Earth, about 10 percent more than the year before. (Photo by Natacha Pisarenko/AP Photo)