A Ballet dancer prepares backstage during the final dress rehearsal for the famous Nutcracker ballet by Pyotr Tchaikovsky at the Joburg Ballet, Johannesburg, South Africa, 04 October 2018. The premiere of Nutcracker is scheduled for 05 October and the show will run for two weeks. (Photo by Kim Ludbrook/EPA/EFE)

Aerial view over mud and waste from the disaster caused by dam spill in Brumadinho, Minas Gerais, Brazil, 26 January 2019. At least nine people have died and 300 are missing after a tailings dam burst at the Feijao mine in southeastern Brazil owned by Vale, the world's largest iron-ore producer, the Minas Gerais state government said. The dam in Brumadinho near Belo Horizonte broke on 25 January at around mid-day, unleashing a river of sludge that destroyed some nearby houses. (Photo by Antonio Lacerda/EPA/EFE)

Policemen detain topless activists of women's rights group Femen, who stage a performance during a protest against Ukrainian President Petro Poroshenko and the government while marking the Day of Dignity and Freedom near the presidential administration headquarters in Kiev, Ukraine November 21, 2017. (Photo by Valentyn Ogirenko/Reuters)

In this January 11, 2018 photo, a skater jumps a ramp during the inauguration of a new recreational space for skateboarders, created in an abandoned gym at the Educational complex Ciudad Libertad, a former military barracks that the late Fidel Castro turned into a school complex after the revolution in Havana, Cuba. Foreign skateboard enthusiasts supply their Cuban counterparts with boards and other equipment. (Photo by Ramon Espinosa/AP Photo)

A Hong Kong Correctional Services Dog Unit (CSDU) officer demonstrates training at the CSDU training facility in Stanley, Hong Kong, China, 27 February 2018. The Hong Kong CSDU consists of 29 staff members divided across six dog teams. According to the department's latest figure from 2017, the average daily penal population of Hong Kong was 8,529. (Photo by Jérôme Favre/EPA/EFE)

A Colombia fan clearly regrets invading the pitch as she is chased by a large security guard during the International Friendly match between Australia and Colombia at Craven Cottage on March 27, 2018 in London, England. (Photo by Charlotte Wilson/Offside/Getty Images)

This image made available by the Johns Hopkins University Applied Physics Laboratory on Wednesday, May 31, 2017 depicts NASA's Solar Probe Plus spacecraft approaching the sun. On Wednesday, NASA announced it will launch the probe in summer 2018 to explore the solar atmosphere. It will be subjected to brutal heat and radiation like no other man-made structure before. (Photo by Johns Hopkins University Applied Physics Laboratory via AP Photo)

Debutantes Amira Rayner, 19 (L) and Eliza Lewis, 17 (R) prepare at Boughton Monchelsea Place ahead of the Queen Charlotte's Ball on September 9, 2017 in Maidstone, England. (Photo by Jack Taylor/Getty Images)