Members of the U.S. Army's Golden Knights parachute team perform during the Bethpage Air Show as part of a Memorial Day event at Jones Beach on Long Island, New York, U.S., May 25, 2019. (Photo by Johnny Milano/Reuters)

Sharafkhaneh port and lake Urmia. Masoud Ghadiri (Iran). The summer Milky Way is very prominent in this photo. On the galaxy zone, Saturn is located besides the Lagoon nebula. On the right of the horizon, you can see the extreme light pollution of Urmia, which is caused by ever-increasing city development. (Photo by Masoud Ghadiri/National Maritime Museum)

Rice seedling festival is a traditional folk festival in longji, guangxi, China on June 9, 2019, during grain in ear season. (Photo by Costfoto/Barcroft Media)

Prime Minister Theresa May meets Russian President Vladimir Putin during the G20 summit in Osaka, Japan on June 28, 2019. (Photo by Stefan Rousseau/PA Images via Getty Images)

Children jump into the water despite strong waves after a strong downpour at Manila's bay, Philippines, Wednesday, July 17, 2019. Schools in metropolitan Manila have been suspended as Tropical Storm Danas, locally named Falcon, continue to enhance the southwest monsoon as it maintains its strength bringing heavy rains over parts of Luzon and Visayas according to the Philippine Atmospheric Geophysical and Astronomical Services Administration. (Photo by Aaron Favila/AP Photo)

This family of warthogs regularly visited our campsite in the Ethiopian highlands so I set up a remote camera with a wide-angle lens to photograph them as they rummaged around for food. They just had a mud bath. (Photo by Will Burrard-Lucas/Caters News Agency)

Iranian bodybuilder Sharareh Nobahari, 30, assists her fitness trainees at a gym in Tehran, Iran on September 20, 2019. (Photo by Nazanin Tabatabaee/Reuters)

Sugar gliders, Candy and Popcorn, enjoy their favourite food, Nectar, at Wild Life Sydney Zoo on February 14, 2017 in Sydney, Australia. The treat made up of honey, high protein baby cereal and egg yolks is the human equivalent to chocolate to the Sugar Gliders. St. Valentine's Day or the Feast of Saint Valentine began as a celebration of the early Christian Saint Valentinus. From the 18th Century onwards it has steadily transformed into a celebration of romantic love and sentiment in many countries around the world. (Photo by James D. Morgan/Getty Images)