When it is almost upon Earth, people experience exhilaration, which is at first assumed to be relief that the comet has no harmful effects; but this is followed by pain and delirium; it is as though the ancient prophecies, once dismissed by astronomers, have been confirmed.

This effect on people's behavior is discovered to be caused by the loss of nitrogen from the atmosphere, leaving pure oxygen, which finally bursts into flame when the comet nucleus hits.

"The Conversation of Eiros and Charmion" was first published in the December 1839 issue of Burton's Gentleman's Magazine and was included that same month in the collection Tales of the Grotesque and Arabesque.

[2] Poe, writing this story in 1839, was capitalizing on the excitement in the 1830s caused by William Miller's predictions of the end of the world.

Olson and Ford also suggest possible sources of Poe's knowledge of both comets: Elijah Hinsdale Burritt's The Geography of the Heavens and John Herschel's 1835 A Treatise on Astronomy.