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)

An Indian girl student covers her face as a precaution against the coronavirus outbreak, in Mumbai, India, 12 March 2020. According to media reports, more than 70 people in India have tested positive for COVID-19. The World Health Organisation declared the novel coronavirus or COVID-19 as global pandemic. (Photo by Divyakant Solanki/EPA/EFE/Rex Features/Shutterstock)

Thai Buddhist monks wear face shields to protect themselves from new coronavirus as they walk to collect alms from devotees in Bangkok, Thailand, Tuesday, March 31, 2020. (Photo by Sakchai Lalit/AP Photo)

Artists wear colourful “deconfinement hats” made of paper mache and inspired by Song dynasty headwear, for social distancing, at 59 Rivoli gallery in Paris as it prepares a general reopening later in the week, following the outbreak of the coronavirus disease (COVID-19) in France, June 3, 2020. (Photo by Benoit Tessier/Reuters)

A Sudanese woman repairs damages to her house, after torrential rain lead to landslides and flash floods, in the town of Umm Dawan Ban, southeast of the capital Khartoum on August 2, 2020. (Photo by Ashraf Shazly/AFP Photo)

Yuri Gagarin does not always show up in full-scale astronautics. In this picture he smiles during his summer vacation in Sochi, Russia in 1961 with sunglasses and sunhat in the camera. (Photo by Imago/Eastnews)

Teens got their glad rags on as they hit the town in Newcastle city centre, United Kingdom on August 16, 2018, as they celebrate their exam results. (Photo by North News and Pictures/NNP)