Terrella (nonfiction)

Kristian Birkeland's magnetized terrella. In this experiment, he noted two spirals which he considered may be similar to that of spiral nebulae.

William Gilbert's terrella.

A terrella (Latin for "little earth") is a small magnetised model ball representing the Earth, that is thought to have been invented by the English physician William Gilbert while investigating magnetism, and further developed 300 years later by the Norwegian scientist and explorer Kristian Birkeland, while investigating the aurora.

Terrellas had been used until the late 20th century to attempt to simulate the Earth's magnetosphere, but have now been replaced by computer simulations.

In the News

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  August 8, 1575: Physician, physicist, and crime-fighter William Gilbert uses his experimental Terrella to stop alleged math criminal Anarchimedes from sabotaging the construction of Tycho Brahe's Uraniborg observatory.

Fiction cross-reference

• Crimes against mathematical constants
• Gnomon algorithm
• Gnomon Chronicles
• Mathematician
• Mathematics

Nonfiction cross-reference

• Kristian Birkeland (nonfiction)
• William Gilbert (nonfiction)
• Mathematician (nonfiction)
• Mathematics (nonfiction)

External links:

• Terrella @ Wikipedia