> According to a 1716 paper mentioned in the book, Hollow Earth: The Long and Curious History of Imagining Strange Lands, Halley devised the Hollow Earth theory as a way to explain strange disturbances in the magnetic field that were connected to the aurora borealis — Earth’s natural light show. Halley was right about the magnetic field, but not so much about Hollow Earth..
> Years later, War of 1812 veteran and explorer, John Cleves Symmes, seized on the Hollow Earth theory.. to justify American expansionism.. into Antarctica. Similar to Halley, Symmes believed that the Earth was made of a hollow shell 800 miles thick, but he added his own twist: there were openings to Earth’s hollow core at both the North and South Pole. These he called “Symmes holes.” There, he believed that light — and human explorers — could descend underneath the surface into the hollow core.
There was also a German sci-fi novel "Two Planets" by Kurd Lasswitz (1897), which influenced a young Werner von Braun who would later contribute to German rocketry and American space program, and write his own sci-fi novel about Mars exploration, https://news.ycombinator.com/item?id=39571588
> According to a 1716 paper mentioned in the book, Hollow Earth: The Long and Curious History of Imagining Strange Lands, Halley devised the Hollow Earth theory as a way to explain strange disturbances in the magnetic field that were connected to the aurora borealis — Earth’s natural light show. Halley was right about the magnetic field, but not so much about Hollow Earth..
> Years later, War of 1812 veteran and explorer, John Cleves Symmes, seized on the Hollow Earth theory.. to justify American expansionism.. into Antarctica. Similar to Halley, Symmes believed that the Earth was made of a hollow shell 800 miles thick, but he added his own twist: there were openings to Earth’s hollow core at both the North and South Pole. These he called “Symmes holes.” There, he believed that light — and human explorers — could descend underneath the surface into the hollow core.
There was also a German sci-fi novel "Two Planets" by Kurd Lasswitz (1897), which influenced a young Werner von Braun who would later contribute to German rocketry and American space program, and write his own sci-fi novel about Mars exploration, https://news.ycombinator.com/item?id=39571588