A girl uses her mobile phone during the evening at the National Park in Khartoum, Sudan, April 24, 2015. (Photo by Mohamed Nureldin Abdallah/Reuters)

Early morning storms over the Masai Mara National Reserve, Kenya on August 26, 2016. (Photo by Action Press/Rex Features/Shutterstock)

A disinfection worker wearing protective gear sprays disinfectant to a medical worker after they perform swab tests for the coronavirus disease (COVID-19) during mass test at Islamic boarding school of Sunan Pandanaran on July 29, 2020 in Yogyakarta, Indonesia. Indonesia is struggling to contain hundreds of new daily cases of coronavirus amid easing of rules to allow economic activity to resume, has reported more than 100,000 coronavirus cases and with at least more 4,900 recorded fatalities. (Photo by Ulet Ifansasti/Getty Images)

A woman takes a selfie in front of a sculpture of a rooster that local media say bears resemblance to U.S. President-elect Donald Trump, outside a shopping mall in Taiyuan, Shanxi province, China December 30, 2016. (Photo by Jon Woo/Reuters)

A man flies a kite on the Bund while buildings of Pudong's Lujiazui financial district stand across the Huangpu River as the sun rises in Shanghai, China, on Friday, October 2, 2015. (Photo by Qilai Shen/Bloomberg)

Fashion from the Phuong My bridal collection is modeled, Thursday April 11, 2019 in New York. (Photo by Bebeto Matthews/AP Photo)

Passengers prepare to take part in the No Pants Subway Ride in Prague, Czech Republic, Sunday, January 8, 2017. The No Pants Subway Ride began in 2002 in New York as a stunt and has taken place in cities around the world since then. (Photo by Petr David Josek/AP Photo)

“Himalayan Dog”. This dog just appeared out of nowhere and followed us for an entire week during our trekking trip in the Himalayan outback. He always used to sleep in front of our tent and guarded us in the nights. When I decided to get up at 4 a.m. to climb the next 5000 m peak for sunrise he accompanied me as well. On the top he was sitting for the entire 30 minutes on this place looking straight into the countryside. Photo location: Ladakh, India. (Photo and caption by Sebastian Wahlhuetter/National Geographic Photo Contest)