A member of a comparsa, a Uruguayan carnival group, dances during the Llamadas parade in Montevideo February 5, 2015. Thousands of people crowd the capital's Barrio Sur as costumed drummers and dancers kick off the street fiesta known as Llamadas which has traditional Afro-Uruguayan roots. The fiesta, also known in Spanish as “The Calls”, started during the colonial period as a slave parade on the city streets. (Photo by Andres Stapff/Reuters)

Macro or Micro? Scientists’ pictures baffle our sense of scale. It began when Stephen Young, a geography professor at Salem State University in Massachusetts, tricked his biologist colleague Paul Kelly into thinking a satellite image was one of his electron microscope scans. Can you guess whether they are close-up or very far away? (Photo by Paul Kelly)

British theoretical physicist Stephen Hawking, Cambridge University Professor and Fellow, circa 1985. Stephen Hawking, the brightest star in the firmament of science, whose insights shaped modern cosmology and inspired global audiences in the millions, has died aged 76. (Photo by Gemma Levine/Getty Images)

Two young women pose for a portrait, dressed in robes after collecting their Bachelor degrees in Conakry on October 12, 2020. Presidential elections are to be held on October 18, with incumbent President bidding for a third term in office, defying critics who say he forced through a new constitution this year enabling him to sidestep two-term presidential limits. (Photo by John Wessels/AFP Photo)

A waitress of The Palais de Tokyo restaurant wears a protective face mask as a precaution against the coronavirus in Paris, Saturday, September 5, 2020. New French cases of COVID-19 jumped in 24 hours to nearly 9,000, health officials said Friday. The 8,975 new cases were the highest number of infections since France successfully grappled with the spread of the coronavirus during a strict two-month lockdown. There were some 1,800 cases less a day earlier and more than for European neighbors. (Photo by Francois Mori/AP Photo)

Edibles are displayed at Shango Cannabis shop on first day of legal recreational marijuana sales beginning at midnight in Portland, Oregon October 1, 2015. The sale of marijuana for recreational use began in Oregon on October 1, 2015 as it joined Washington state and Colorado in allowing the sale of a drug that remains illegal under U.S. federal law. (Photo by Steve Dipaola/Reuters)

A girl wearing a mask takes part in a procession celebrating the religious holiday of Mawlid al-Nabi, the birthday of Prophet Mohammad, in Benghazi, Libya December 10, 2016. (Photo by Esam Omran Al-Fetori/Reuters)

Performer from the Mangueira samba school parades during carnival celebrations at the Sambadrome in Rio de Janeiro, Brazil, Tuesday, February 9, 2016. (Photo by Silvia Izquierdo/AP Photo)