Editing Halley's Comet (section)

===1910===
{{multiple image
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|image1=Halley's comet 1910 (cropped).jpg
|caption1=Halley's Comet in April 1910, photographed from [[Arequipa]], Peru
|image2=Halley's Comet - May 29 1910.jpg
|caption2=A photograph of Halley's Comet taken at [[Yerkes Observatory]] on 29 May 1910
|alt2=Black-and-white picture of the comet, its nucleus brilliant white, and its tail very prominent, moving up and to the right
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The 1910 approach, which came into naked-eye view around 10 April<ref name="greatcomets"/> and came to perihelion on 20 April,<ref name="greatcomets"/> was notable for several reasons: it was the first approach of which photographs exist, and the first for which [[spectroscopic]] data were obtained.<ref name="post"/> Furthermore, the comet made a relatively close approach of 0.15 au,<ref name="greatcomets"/> making it a spectacular sight. Indeed, on 19 May, Earth actually passed through the tail of the comet.<ref name="Ridpath"/><ref name="pfizer"/> One of the substances discovered in the tail by spectroscopic analysis was the toxic gas [[cyanogen]],<ref name="NYTimes_19100208"/> which led press to misquote the astronomer [[Camille Flammarion]] by stating he claimed that, when Earth passed through the tail, the gas "would impregnate the atmosphere and possibly snuff out all life on the planet".{{sfnm|Goodrich|2023|1p=83|Goodrich|2023|2p=238}}<ref name="smith"/> Despite reassurances from scientists that the gas would not inflict harm on Earth,<ref name="smith"/> the damage had already been done with members of the public [[panic buying]] gas masks and [[Quackery|quack]] "anti-comet pills".{{sfn|Goodrich|2023|p=188}}

The comet added to the unrest in China on the eve of the [[Xinhai Revolution]] that would end the [[Qing dynasty|last dynasty]] in 1911.<ref name="TingChen2022"/> As James Hutson, a missionary in [[Sichuan]] Province at the time, recorded:

<blockquote>"The people believe that it indicates calamity such as war, fire, pestilence, and a change of dynasty. In some places on certain days the doors were unopened for half a day, no water was carried and many did not even drink water as it was rumoured that pestilential vapour was being poured down upon the earth from the comet."<ref name="Hutson1921"/></blockquote>

The 1910 visitation coincided with a visit from [[Hedley Churchward]], the first known English Muslim to make the Haj pilgrimage to [[Mecca]].<ref name="Rosenthal1931"/>

The comet was used in an advertising campaign of [[Le Bon Marché]], a well-known department store in Paris.<ref name="Bibliothèque_numérique"/>

The comet was also fertile ground for [[hoaxes]]. One that reached major newspapers claimed that the Sacred Followers, a supposed [[Oklahoma]] religious group, attempted to sacrifice a virgin to ward off the impending disaster, but were stopped by the police.<ref name="Johnson1997b"/>

American satirist and writer [[Mark Twain]] was born on 30 November 1835, exactly two weeks after the comet's [[Perihelion and aphelion|perihelion]]. In his autobiography, published in 1909, he said,

<blockquote>I came in with Halley's comet in 1835. It is coming again next year, and I expect to go out with it. It will be the greatest disappointment of my life if I don't go out with Halley's comet. The Almighty has said, no doubt: "Now here are these two unaccountable freaks; they came in together, they must go out together."<ref name="Paine1912"/><ref name="Metcalf2009"/></blockquote>

Twain died on 21 April 1910, the day following the comet's subsequent perihelion.<ref name="Cleere1985"/><ref name="Chautauquan1910"/> The 1985 fantasy film ''[[The Adventures of Mark Twain (1985 film)|The Adventures of Mark Twain]]'' was inspired by the quotation.<ref name="TwainMovie"/>

Halley's 1910 apparition is distinct from the [[Great January Comet of 1910|Great Daylight Comet of 1910]], which surpassed Halley in brilliance and was visible in broad daylight for a short period, approximately four months before Halley made its appearance.<ref name="Comet1910"/><ref name="Bortle1998"/>