Members of the SubCielo company perform during the fifth annual Puerto Rico Circo Fest in San Juan, Puerto Rico, Saturday, March 10, 2018. The festival is held simultaneously in several spots on the streets of the Old San Juan city on March 10–11. (Photo by Ricardo Arduengo/AFP Photo)

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)

South Vietnamese forces escort suspected Viet Cong officer Nguyen Van Lem (also known as Bay Lop) on a Saigon street February 1, 1968, early in the Tet Offensive. Moments later, Lem was executed by Gen. Nguyen Ngoc Loan, chief of the national police. (Photo by Eddie Adams/AP Photo)

Ariana Lamcellari, 4, holds a sign at a protest against violence, following the charge of a British police officer in the London kidnapping and murder of Sarah Everard, in Dublin, Ireland on March 16, 2021. (Photo by Clodagh Kilcoyne/Reuters)

A prong extending from a remote-controlled robot prototype approaches the mouth of a volunteer to extract a throat swab sample, as part of a self-funded project to assist physicians in running tests on suspected COVID-19 coronavirus patients in a bid to limit human exposure to disease-carriers, at a private hospital in Egypt's Nile delta city of Tanta, on March 20, 2021. (Photo by Khaled Desouki/AFP Photo)

An Iranian girls a bag of goldfish ahead of Nowruz, the Iranian New Year, in Tehran, Iran on March 17, 2021. (Photo by Majid Asgaripour/WANA (West Asia News Agency) via Reuters)

A local resident performs traditional horse racing during a celebration marking the 70th anniversary of the founding of Yushu Tibetan Autonomous Prefecture, in northwest China's Qinghai Province, August 4, 2021. (Photo by Xinhua News Agency/Rex Features/Shutterstock)

A Shi'ite Muslim woman bleeds after she was cut on the forehead with a razor during a religious procession to mark Ashura in Nabatieh, southern Lebanon on August 19, 2021. (Photo by Aziz Taher/Reuters)