Passengers wait at the departure hall of the Beijing Railway Station in central Beijing, China January 27, 2017 as China gears up for Lunar New Year, when hundreds of millions of people head home. (Photo by Damir Sagolj/Reuters)

George Harrison of the Beatles sits cross-legged with his musical mentor, Ravi Shankar of India, a sitar virtuoso, in Los Angeles, August 3, 1967, as Harrison explains to newsmen that Shankar is teaching him to play the sitar, a 25-stringed guitar-like instrument. Harrison said “Indian music makes God come through in a spiritual way”. (Photo by AP Photo)

A hint of Spring Fever is evidenced by this passerby tipping his hat to a store fixture mannequin on a State St. sidewalk in downtown Chicago on March 23, 1978. The mannequin was awaiting pickup to be transported. (Photo by AP Photo)

German troops in Stalingrad, USSR. September 10, 1942. (Photo by TASS)

An air raid drill at Seattle College caught students William Bates, left, and Edna Mae Farrell, right, while they were eating their lunch in the school café, but they simply took shelter under the table and continued eating in Seattle, Washington, March 17, 1942. Air raid wardens said 350 students left their classrooms and assembled in shelters within one minute in first at the college. (Photo by AP Photo)

Cambridge policemen, known as “Bulldogs”, lined up for the University Bulldogs Chase, dressed in morning coats and top hats, 7th March 1936. (Photo by H. Allen/Topical Press Agency/Getty Images)

A Muslim pilgrim makes his way to Hera cave, where Muslims believe Prophet Mohammad received the first words of the Koran through Gabriel, at the top of Mount Al-Noor during the annual haj pilgrimage in the holy city of Mecca, September 21, 2015. (Photo by Ahmad Masood/Reuters)

An aerial view of the holy Muslim Shiite shrine of Imam Moussa al-Kazim as pilgrims gather to commemorate his death, in the Shiite district of Kazimiyah, Baghdad, Iraq, Wednesday, May 13, 2015. The anniversary of 8th century Shiite Imam Moussa al- Kazim drew tens of thousands of Shiites from all walks to converge on his golden-domed shrine in northern Baghdad. The pilgrims typically march to the shrine while hundreds of tents are erected to offer them free food, drinks and services. (Photo by Hadi Mizban/AP Photo)