A Chesterfield Borough Police telephone operator tests a gasmask with built in earpiece and microphone. The telephone service is considered one of the most important links in the coordination of ARP operations and must remain operational during air raids, 12th April 1939. (Photo by Fox Photos/Hulton Archive/Getty Images)

People watch a total solar eclipse from the Bay Bridge in Palu, Central Sulawesi, Indonesia March 9, 2016 in this photo taken by Antara Foto. The rare astronomical event is being witnessed Wednesday along a narrow path that stretches across 12 provinces encompassing three times zones and about 40 million people. (Photo by Mohamad Hamzah/Reuters/Antara Foto)

In this April 13, 2015 file photo, a Thai woman splashes water on people from the back of a truck during the Songkran water festival to celebrate Thai New Year in Bangkok, Thailand.Thailand's military government is putting a dampener on the annual nationwide water fight. Despite Thailand's worst drought in 20 years, the junta says it has no intention of limiting the virtually around-the-clock water throwing that defines the three-day Songkran festival. Instead, it has decided to impose morality measures. (Photo by Sakchai Lalit/AP Photo)

An attendee takes a selfie at KCON USA, billed as the world's largest Korean culture convention and music festival, in Los Angeles, California on August 11, 2018. K-pop acts sing or rap in Korean, often with snippets of English. On the Web, where K-pop fandom thrives, many music videos include subtitles. (Photo by Mike Blake/Reuters)

An Indian Sikh devotee spits fire as he performs during religious procession ahead of the birth anniversary of the first Sikh Guru or master, Sri Guru Nanak Dev Ji, the founder of Sikhism, in Jammu, the winter capital of Kashmir, India, 21 November 2018. The birth anniversary of Guru Nanak Dev Ji will be observed on 23 November 2018. (Photo by Jaipal Singh/EPA/EFE)

A woman reacts after identifying a relative among the bodies of tsunami victims in Carita, Indonesia, Sunday, December 23, 2018. The tsunami occurred after the eruption of a volcano around Indonesia's Sunda Strait during a busy holiday weekend, sending water crashing ashore and sweeping away hotels, hundreds of houses and people attending a beach concert. (Photo by Fauzy Chaniago/AP Photo)

A street artist makes soap bubbles in front of the Alte Nikolaikirche church at the Roemerberg square in Frankfurt am Main, western Germany, on August 12, 2018. (Photo by Frank Rumpenhorst/DPA/AFP Photo)

A Vietnamese cosplayer poses as police officer character from the game during the League of Legends (LOL) Mid-Season Invitational 2019 play-in group stage, in GG Stadium, Ho Chi Minh, Vietnam May 5, 2019. (Photo by Reuters/Kham)