An overcrowded dinghy with migrants from different African countries is followed by members of the German NGO Jugend Rettet as they approach the Iuventa vessel during a rescue operation, off the Libyan coast in the Mediterranean Sea September 21, 2016. (Photo by Zohra Bensemra/Reuters)

A group of people are seen on a Victoria line train in London, England during the first night of the Night Tube service on August 19 2016. The Central line and Victoria line are the first to operate a Night service with further lines expected to be running by the end of the year. (Photo by SWNS.com)

A graffiti, portraying a woman, is seen in Medellin, Colombia on November 19, 2017. Mural graffitis from different artists, street art can be seen in almost every city on Earth, but street arts raw power and potential for change was felt by me most intensively in Medellins Comuna 13, previously one of Colombias most dangerous neighbourhoods, in fact Communa 13 was constant battleground between gangs, narcos, paramilitaries and the government, but today you would hardly recognise it. (Photo by Juancho Torres/Anadolu Agency/Getty Images)

A tattoo of a weapon covers the arm of a female inmate waiting to compete in the annual beauty contest at Talavera Bruce penitentiary in Rio de Janeiro, Brazil, early Thursday, November 23, 2017. Jail authorities say they organize the annual contest to encourage self-esteem, fight idleness and promote integration among women prisoners. (Photo by Silvia Izquierdo/AP Photo)

Revelers celebrate during fireworks marking the start of the New Year on Copacabana beach on January 1, 2017 in Rio de Janeiro, Brazil. (Photo by Mario Tama/Getty Images)

A man takes a photograph of his friend as thick smoke rises from a fire, which broke out at oil wells set ablaze by Islamic State militants before they fled the oil-producing region of Qayyara, Iraq, January 28, 2017. (Photo by Muhammad Hamed/Reuters)

Firefighters carry a woman on a stretcher after a car drove into the crowded seaside boardwalk along Copacabana beach in Rio de Janeiro, Brazil, Thursday, January 18, 2018. Military police said on Twitter that at least 11 people were injured and that the driver has been taken into custody. (Photo by Silvia Izquierdo/AP Photo)

A SpaceX Falcon Heavy rocket lifts off from historic launch pad 39-A at the Kennedy Space Center in Cape Canaveral, Florida, February 6, 2018. The world' s most powerful rocket, SpaceX' s Falcon Heavy, blasted off Tuesday on its highly anticipated maiden test flight, carrying CEO Elon Musk' s cherry red Tesla roadster to an orbit near Mars. Screams and cheers erupted at Cape Canaveral, Florida as the massive rocket fired its 27 engines and rumbled into the blue sky over the same NASA launchpad that served as a base for the US missions to Moon four decades ago. (Photo by Thom Baur/Reuters)