Case file · High strangeness
Halley's hollow Earth
In 1692 the astronomer Edmond Halley told the Royal Society that the Earth might be a shell about 800 km thick around two inner shells and a core, each with its own magnetic poles, perhaps lit and inhabited.
1692 CE · 51.51, -0.10 · status: explained
The account
Halley proposed the idea to explain shifting compass readings, and he suggested that escaping glowing gas caused the aurora. It was a serious hypothesis by the standards of the time and inspired later hollow-earth enthusiasts.
The sceptical view
Measurements of the Earth's density, from Hutton's Schiehallion work around 1774, and later seismology show a dense solid and liquid interior.
Connections in the atlas
- Kircher's 'Mundus Subterraneus'
- 'The Smoky God': Olaf Jansen's inner world
- Symmes's hollow-earth circular