Vehicles pass through the heavy fog and air pollution that cover Skopje valley in the early morning, in Skopje, The Former Yugoslav Republic of Macedonia, 14 December 2017. According to media reports, Skopje is considered one of the most polluted cities in the world. (Photo by Georgi Licovski/EPA/EFE)

People in funny costumes race down the slope in bathtubs during the 7th Bathtub race at Stoos, Switzerland, on January 19, 2019. (Photo by Urs Flueeler/EPA/EFE/Rex Features/Shutterstock)

A hummingbird feeds on the nectar from a Mimosa tree in Saugus, Massachusetts on July 30, 2020. (Photo by Joseph Prezioso/ZUMA Wire/Rex Features/Shutterstock)

Girls wearing protective face masks wait to pray inside temple premises on the occasion of the annual harvest festival of Onam on the outskirts of Kochi, India, August 31, 2020. (Photo by Sivaram V/Reuters)

The International Space Station (ISS) moving in front of the sun in November 2020 by astrophotographer Andrew McCarthy. These incredible photos capture the clearest images ever taken of the International Space Station (ISS) moving in front of both the moon and the sun. The photos, taken within days of one another, were captured in the space of less than a second, as the space station could be clearly seen zooming across against the bright backdrops of both moon and sun. Photographer Andrew McCarthy, from California, USA, said the photo of the ISS in front of the sun, in broad daylight, was “one of my trickiest shots ever”. (Photo by Andrew McCarthy/South West News Service)

A Student of Yuba Pratibha School, wearing a face shield and masks at school during a coronavirus pandemic in Kathmandu, Nepal, 26 November 2020. The head Teacher of Yuba Pratibha School, Yanga Raj Dahal, started to conduct classes for students, who can’t afford and attend online classes, with strict sanitary regime, providing also free face masks and shields for students. However majority of schools have been conducting online classes in Nepal from 19 March 2020 as part of precautionary measures against the spread of the coronavirus Covid-19. (Photo by Narendra Shrestha/EPA/EFE)

A girl carries sorghum stalks during the sorghum harvest season in Amran province, Yemen, October 24, 2020. (Photo by Xinhua News Agency/Rex Features/Shutterstock)

U.S. President Donald Trump holds news conference on the coronavirus outbreak at the White House in Washington, U.S., February 26, 2020. (Photo by Carlos Barria/Reuters)