Walkers cross the river Waalbrug during the first day of the 98th annual four-days walking event, the “Vierdaagse” in Nijmegen, Netherlands, July 15, 2014. The “Nijmeegse Vierdaagse” is an annual public four-day field march which is held since 1909 in the third week of July. (Photo by Erik van 't Wout/EPA)

An Indian girl smiles under a water splash at a water park as the temperatures reached 38 degree Celsius in Calcutta, eastern India, 12 June 2016. The summer or pre-monsoon season lasts from March to July in eastern India with the highest day temperatures ranging from 38 to 45 degrees Celsius. (Photo by Piyal Adhikary/EPA)

Japan's Kana Muramoto and Chris Reed compete in the figure skating team event ice dance short dance during the Pyeongchang 2018 Winter Olympic Games at the Gangneung Ice Arena in Gangneung on February 11, 2018. (Photo by John Sibley/Reuters)

Netherland's Kitty van Male is hit in the face by Argentina's Agustina Habif during the women's quarterfinal field hockey game, August 15, 2016. (Photo by Carl de Souza/AFP Photo)

In this March 12, 2015 photo, a man tours a graffiti exhibition at the Museum of Modern Art, in Bogota, Colombia. The city-run museum recently held an exhibition highlighting the work of Bogota street artists who go by aliases such as Joems and the MonsTruacioN collective. (Photo by Fernando Vergara/AP Photo)

Villagers use a makeshift bamboo bridge to move across flooded areas of Morigaon district in the northeastern Indian state of Assam August 20, 2014. The latest heavy rains have caused landslides and floods in many parts of India and Nepal, where at least 90 people have been killed since Thursday. (Photo by Reuters/Stringer)

This February 7, 2018, photo shows João Lousada, a flight controller for the International Space Station, wearing an experimental space suit during a simulation of a future Mars mission in the Dhofar desert of southern Oman. The desolate desert in southern Oman resembles Mars so much that more than 200 scientists from 25 nations organized by the Austrian Space Forum are using it for the next four weeks to field-test technology for a manned mission to Mars. (Photo by Sam McNeil/AP Photo)

A prong extending from a remote-controlled robot prototype approaches the mouth of a volunteer to extract a throat swab sample, as part of a self-funded project to assist physicians in running tests on suspected COVID-19 coronavirus patients in a bid to limit human exposure to disease-carriers, at a private hospital in Egypt's Nile delta city of Tanta, on March 20, 2021. (Photo by Khaled Desouki/AFP Photo)