Volunteers wearing face masks, gloves and protective gear to protect against coronavirus, gather to clean an area of an outdoor book market set up at Red Square with GUM, State Department store, left, St. Basil's Cathedral, center, Spasskaya Tower, second with, and the Kremlin Wall, right, in Moscow, Russia, Saturday, June 6, 2020. Muscovites clad in face masks and gloves ventured into Red Square for an outdoor book market, a small sign of the Russian capital's gradual efforts to open up amid coronavirus concerns. (Photo by Alexander Zemlianichenko/AP Photo)

Pigeons cool down at a public fountain on a hot summer day at University Plaza in downtown Bucharest, Romania, 10 June 2020. Temperatures in Bucharest reached 30 degrees Celsius. (Photo by Robert Ghement/EPA/EFE)

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)

A model presents a creation from Dior's Cruise 2021 collection during a live-streamed runway show without an audience due to the coronavirus disease (COVID-19) outbreak, at the Piazza del Duomo, in Lecce, Italy on July 22, 2020. Christian Dior hosted a live but audience-free fashion show in the Italian city of Lecce, in a dazzling celebration of local crafts and traditions that included a dance spectacle in the middle of the baroque main square. (Photo by Alessandro Garofalo/Reuters)

An Indian worker crosses a street holding a shovel during monsoon rains in Prayagraj, in the northern Indian state of Uttar Pradesh, Wednesday, July 29, 2020. (Photo by Rajesh Kumar Singh/AP Photo)

A man and a woman take a selfie on Russian Navy Day in St Petersburg, Russia on July 26, 2020. (Photo by Roman Pimenov/TASS)

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 USGS geologist making observations of the fissure 8 lava channel at sunset is pictured in this July 3, 2018 fisheye lens handout photograph near the Kilauea volcano eruption in Hawaii, U.S. (Photo by USGS/Handout via Reuters)