An abandoned protection masks in the deserted building near bypass channel for cooling at the Chernobyl nuclear power plant in the Exclusion Zone, Ukraine, April 5, 20177. The Chernobyl nuclear accident occurred on 26 April 1986 in the No.4 light water graphite moderated reactor at the Chernobyl Nuclear Power Plant near Pripyat. An estimated 47,000 people of the city of Pripyat were evacuated after the explosion in 1986. (Photo by Vitaliy Holovin/Corbis via Getty images)

In this May 8, 2015 photo, sisters Zoraida Infante, left, and Graciela Trujillo pray on Fishermen's Beach before therapeutic swimming in the Pacific Ocean in Lima, Peru. Under overcast skies, the bathers practice thalassotherapy, which derives from the Greek “thalasso”, for “sea”, and draws on the ocean's healing properties. (Photo by Rodrigo Abd/AP Photo)

Subway passengers walk past bronze sculptures representing the Soviet people at the Ploshchad Revolyutsii metro station in Moscow, on November 14, 2012. The station was opened in 1938. (Photo by Kirill Kudryavtsev/AFP Photo)

The Haʻikū Stairs, also known as the Stairway to Heaven or Haʻikū Ladder, is a steep hiking trail on the island of Oʻahu. The trail began as a wooden ladder spiked to the cliff on the south side of the Haʻikū Valley. It was installed in 1942 to enable antenna cables to be strung from one side of the cliffs above Haʻikū Valley to the other. A building to provide a continuous communication link between Wahiawā and Haʻikū Valley Naval Radio Station was constructed at the peak of Puʻukeahiakahoe, elevation about 2,800 feet (850 m). The antennae transmitted very low frequency radio signals from a 200,000-watt Alexanderson alternator in the center of Haʻikū valley. The signals could reach US Navy submarines as far away as Tokyo Bay while the submarines were submerged.

A woman walks with her daughter through an empty street on April 27, 2020 in Malaga, Spain. Since April 27 children under 12 are allowed to come and go from their homes more freely. Spain has had more than 209,000 confirmed cases of COVID-19 and over 23,000 reported deaths, although the rate has declined after weeks of lockdown measures. (Photo by Daniel Perez Garcia-Santos/Getty Images)

People in quarantine exercise in front of their homes amid Covid-19 full lockdown of the city in Shanghai, China, 27 April 2022. According to the Shanghai Health Commission on 27 April, there were 48 new Covid-19 deaths, 1,606 locally transmitted cases, and 11,956 local asymptomatic infections, in Shanghai city. Despite the death toll rising in Shanghai, the number of daily infections has gradually declined. (Photo by Alex Plavevski/EPA/EFE)

A Nepalese army solder stand next to a horse during the “Ghodejatra” Horse Race festival, which is organised by the Nepal Army, in Kathmandu, Nepal, April 7, 2016. Ghode Jatra, the horse racing festival of Nepal, celebrated on the New Moon day of mid March or early April is among the important celebrations of the Kathmandu Valley. Grand horse parade including various acrobatic style of shows are performed by Nepal military at Tundikhel-a fenced parade ground located in the heart of Kathmandu city. (Photo by Navesh Chitrakar/Reuters)

This aerial photograph taken on April 22, 2024 shows a flooded island after heavy rains in Qingyuan, in southern China's Guangdong province. More than 100,000 people have been evacuated due to heavy rain and fatal floods in southern China, with the government issuing its highest-level rainstorm warning for the affected area on April 23. (Photo by AFP Photo/China Stringer Network)