Alexis kneels with his baby at a protest in solidarity with the Black Lives Matter movement in Dakar, Senegal on June 9, 2020. (Photo by John Wessels/AFP Photo)

A counter-protester gestures during a Black Lives Matter protest following the death of George Floyd in Minneapolis police custody, in London, Britain, June 13, 2020. (Photo by Simon Dawson/Reuters)

Amundsen-Scott South Pole Station experiences months of darkness. The sun dips below the horizon on March 21, after which follows several weeks of twilight before complete darkness results. Photo taken on June 25, 2009. (National Science Foundation/Jeremy Johnson)

A demonstrator holds up her fist, in front of police officers during a protest, organised by Black Lives Matter Belgium, against racial inequality in the aftermath of the death in Minneapolis police custody of George Floyd, in central Brussels, Belgium on June 7, 2020. (Photo by Yves Herman/Reuters)

A woman stands in front of police officers during a Black Lives Matter protest in London, following the death of George Floyd who died in police custody in Minneapolis, London, Britain, June 7, 2020. (Photo by Dylan Martinez/Reuters)

Police spraying protesters with pepper spray inside Central Station after a Black Lives Matter rally in Sydney, Australia, 06 June 2020, a protest against the deaths of Aboriginal people in custody and solidarity with the US protests for George Floyd. (Photo by James Gourley/EPA/EFE)

A thrill-seeking storm chaser captured the precise moment these giant lightning bolts lit up dark skies in a series of incredible storms. (Photo by Craig Eccles/Solent News & Photo Agency)

Light sculptures glow in the dark at the zoo in Cologne, Germany, 04 December 2019. The artworks are on display at the zoo as part of the China Light Festival that runs until 09 January 2020 and features more than 70 light installations on the zoo grounds. (Photo by Sascha Steinbach/EPA/EFE)