---
node: galileo_galilei
type: person
slug: galileo_galilei
title: "Galileo Galilei"
lead: "Galileo Galilei was an Italian astronomer, physicist, and mathematician, a central figure of the Scientific Revolution."
published: 2026-07-11
updated: 2026-07-11
image_file: galileo_galilei.jpg
image_source: "https://commons.wikimedia.org/wiki/File:Justus_Sustermans_-_Portrait_of_Galileo_Galilei,_1636.jpg"
image_author: "Justus Sustermans"
image_license: "Public domain"
---

## Who they were

Galileo Galilei was an Italian astronomer, physicist, and mathematician, a central figure of the Scientific Revolution.

## What they did

He improved the telescope and observed the moons of Jupiter, the phases of Venus, and lunar craters, supporting Copernican heliocentrism; his advocacy led the Roman Inquisition to try him in 1633, forcing him to recant and spend his last years under house arrest. He also advanced the study of motion.

## Legacy

Often called the father of modern observational astronomy and of modern physics, he became a symbol of the conflict between science and dogma, and the Church acknowledged errors in his condemnation only centuries later.