astronomy: Galileo's Telescope

Galileo Galilei (1564–1642) made fundamental discoveries in both astronomy and physics; he is perhaps best described as the founder of modern science. Galileo was the first to make astronomical use of the telescope. His discoveries of the four largest moons of Jupiter and the phases of Venus were persuasive evidence for the Copernican cosmology. His discoveries of craters on the moon and blemishes on the sun (sunspots) discredited the ancient belief in the perfection of the heavens. These findings were announced in The Sidereal Messenger, a small book published in 1610. Galileo's Dialogue on the Two Chief Systems of the World (1632) was an eloquent argument for the Copernican system over the Ptolemaic. However, Galileo was called before the Inquisition and forced to renounce publicly all doctrines considered contrary to Scripture.

Sections in this article:

• Introduction
• Modern Techniques, Discoveries, and Theories
• Astrophysical Discoveries
• Galileo's Telescope
• Brahe and Kepler
• The Copernican Revolution
• The Alexandrian School and the Ptolemaic System
• Greek Innovations
• Ancient Astronomy
• Bibliography

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