Air Force One casts its shadow over homes as it comes in to land in Allentown, Pennsylania with U.S. President George W. Bush aboard in this October 1, 2004 file photo. (Photo by Jason Reed/Reuters)

Elephants are paraded in front of the Grand Palace to pay respects to the late Thai King Bhumibol Adulyadej in Bangkok on October 8, 2016. Thailand' s King Bhumibol Adulyadej died at the age of 88 on October 13 after years of ill health, ending a seven- decade reign and leaving the politically divided nation without its key pillar of unity. (Photo by Lillian Suwanrumpha/AFP Photo)

Passengers check their mobile devices as a bin is full of garbage during a protest by the cleaning staff at Barcelona's airport, Spain, December 1, 2016. (Photo by Albert Gea/Reuters)

An artistic light installation illuminates the canal near the Brussels district of Molenbeek during the Bright Brussels Festival in Brussels, Belgium February 4, 2017. (Photo by Francois Lenoir/Reuters)

Bicycles of various bike-sharing services are seen at an urban village in smog during a polluted day in Shanghai, 2017. Rapid expansion of shared bicycle companies across China has led to massive piles of abandoned bikes as supply outstrips demand. (Photo by Aly Song/Reuters)

An ice hockey-themed crew in the 2018 Zaplyv festival of handmade inflatables in 300 Years of St Petersburg Park in St Petersburg, Russia on August 5, 2018. (Photo by Peter Kovalev/TASS)

A visitor passes behind the sculpture “Puma-Dentist” made with plastic, wax and original heads of a puma and a hind by Austrian artist Deborah Sengl during an exhibition at the art gallery Deschler in Berlin April 15, 2008. (Photo by Fabrizio Bensch/Reuters)