The Aurora Borealis (Northern Lights) is seen over the sky near Inari in Lapland, Finland on February 14, 2019. (Photo by Alexander Kuznetsov/Reuters)

A man walks by as tourists take selfies on the French Riviera city of Nice on June 24, 2019, as temperatures soar to 33 degrees Celsius. Forecasters say Europeans will feel sizzling heat this week with temperatures soaring as high as 40 degrees Celsius (104 degrees Fahrenheit) in an “unprecedented” June heatwave hitting much of Western Europe. (Photo by Valery Hache/AFP Photo)

A moto-taxi driver takes two passengers past a burning barricade set up by people protesting fuel shortages in Port-au-Prince, Haiti, Monday, September 16, 2019. Haiti was at a standstill Monday with no public transportation available and closed banks, government offices, and schools amid street protests due to a fuel crisis. (Photo by Dieu Nalio Chery/AP Photo)

A mahout sits between elephants which are participating in festivities marking the annual harvest festival of Onam at a temple on the outskirts of Kochi, India, September 11, 2019. (Photo by Sivaram V/Reuters)

Protesters shield themselves as police beat them with sticks during a violent demonstration near the India Gate against a gang rape and brutal beating of a 23-year-old student on a bus last week, in New Delhi, India, December 23, 2012. The attack last Sunday has sparked days of protests across the country. (Photo by Kevin Frayer/Associated Press)

A man prays to mourn victims of the March 11, 2011, earthquake and tsunami in front of a ship brought ashore by the disaster in Kesennuma, Miyagi Prefecture, Japan. (Photo by Kyodo via Reuters)

Harris & Ewing Inc. photographed people, events, and architecture, particularly in Washington, D.C., during the period 1905-1945. Photo: Tests of Curtiss Palne for Army, Single Control. Created by Harris & Ewing. Published in 1912.

A demonstrator wears a message on a t-shirt in Tahrir Square on May 27, 2011 in Cairo, Egypt. The ruling Supreme Council of the Armed Forces said that there would be no use of violence against protests dubbed “the Second Revolution of Anger” taking place in Cairo and other cities in Egypt. (Photo by Peter Macdiarmid/Getty Images)