Wu Lingling, a nurse from Central Hospital of Shanghai Fengxian District says goodbye to her husband Zhao Kun before leaving for Wuhan at Shanghai South Railway Station in east China's Shanghai, January 27, 2020. A team comprised of 50 medical workers from 40 hospitals in Shanghai left for Wuhan City on Monday to aid the novel coronavirus control efforts there. (Photo by Ding Ting/Xinhua News AgencyAlamy Live News)

An unidentified man brandishes a gun during a protest against a new citizenship law outside the Jamia Millia Islamia University in New Delhi, India, January 30, 2020. The gunman went live on Facebook to warn he was taking his “final journey” before firing at the protest. (Photo by Danish Siddiqui/Reuters)

Tourists sit around a bonfire on the Makgadikgadi salt pan in Botswana. (Photo by Yang Mengxi/Xinhua News Agency/Barcroft Media)

The comet Neowise, or C/2020 F3, is seen in the evening sky above the artwork titled: “Seven Magic Mountains” by artist Ugo Rondinone, Thursday, July 16, 2020, near Jean, Nev., south of Las Vegas. (Photo by John Locher/AP Photo)

Jolon Clinton, 15, (L), and her sister, Halcy, 17, take photos of a fissure near their home on the outskirts of Pahoa during ongoing eruptions of the Kilauea Volcano in Hawaii, U.S., May 14, 2018. (Photo by Terray Sylvester/Reuters)

A woman with high heels walks on a sidewalk which is renovated on August 10, 2017 in downtown Moscow, as the city continues with preparations for next year's FIFA World Cup. (Photo by Mladen Antonov/AFP Photo)

A hummingbird is photographed during the National Orchid Exhibition at the Jose Celestino Mutis Botanical Garden in Bogota, Colombia Septermber 20, 2018. Picture taken September 20, 2018. (Photo by Luisa Gonzalez/Reuters)

A swarm of starlings flies over the Altare della Patria monument (Unknown soldier) in the city centre of Rome during sunset, on November 27, 2018. (Photo by Vincenzo Pinto/AFP Photo)