which scientist was arrested for arguing that the sun—not the earth—was the center of the solar system?

The scientist you are looking for is Galileo Galilei.
Quick Scoop
- Galileo Galilei supported and defended the heliocentric model, which says the Sun is at the center of the solar system and the Earth moves around it.
- In 1633, the Roman Inquisition tried him for heresy because of his promotion of this idea, and he was found “vehemently suspect of heresy.”
- He was forced to recant his views and spent the rest of his life under house arrest, which is the “arrest” people usually refer to in this context.
Why not Copernicus?
- Nicolaus Copernicus first presented the heliocentric model in full in 1543, but he was not arrested or executed for it.
- Opposition to heliocentrism became much sharper later, and Galileo’s outspoken defense and style of argument brought him into direct conflict with Church authorities.
TL;DR: The scientist associated with being arrested for arguing that the Sun, not the Earth, is at the center of the solar system is Galileo Galilei , not Copernicus.
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