“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)

A picture taken on March 16, 2017 shows women dressed up as mermaids posing by a pool at a mermaid training school in Moscow. Russian women who have dreamt of becoming a mermaid since their youngest years, start turning their fantasies into reality with a new type of fitness – mermaid swimming. (Photo by Natalia Kolesnikova/AFP Photo)

A group of fashionable nonagenarians pose for a photo in Pengzhou, Sichuan, China on October 12, 2016. (Photo by Rex Features/Shutterstock)

Artist German Vinogradov acts in the performance of the burning of installation, devoted to Maslenitsa, or Pancake Week, a pagan holiday marking the end of winter, in the village of Nikola-Lenivets, Kaluga region, Russia, February 17, 2018. (Photo by Maxim Shemetov/Reuters)

Visitors take photos of the fluorescent sea in the waters of Paishi Village, Dalian City, Liaoning Province, China, May 24, 2020, from the night of May 24 to the early morning of May 25, 2020. The fluorescent sea in dalian is caused by noctilucent algae in the sea water. (Photo by Costfoto/Barcroft Media via Getty Images)

A vendor pushes an improvised cart with a woman and merchandise along a rarely used rail track in Bangkok, Thailand, Thursday, June 25, 2020. Daily life in the capital slowly returns to normal as the Thai government eases many restrictions imposed weeks ago to combat the spread of COVID-19. Though emergency regulations require the use of face masks in public, some residents have become apathetic as Thailand has record zero local transmission for over three weeks. (Photo by Gemunu Amarasinghe/AP Photo)

Astronauts Nie Haisheng (C), Liu Boming (R) and Tang Hongbo are out of the return capsule of the Shenzhou-12 spaceship at the Dongfeng landing site in north China's Inner Mongolia Autonomous Region on September 17, 2021. Three Chinese astronauts, the first sent to orbit for space station construction, have completed their three-month mission and returned to Earth safely on Friday. Photo by Lian Zhen/Xinhua News Agency)

A woman shouts slogans as she marches to Congress to commemorate International Women's Day in Buenos Aires, Argentina, Monday, March 9, 2020. (Photo by Natacha Pisarenko/AP Photo)