Question

Galileo's observations of the phases of Venus proved

a. that Venus orbited the Sun.
b. that Earth orbited the Sun.
c. that all of the planets orbited Earth.
d. that the Moon orbited Earth.
e. that Venus had an atmosphere.
f. nothing.

Answer 1

Galileo's observation of the phases of Venus provided evidence that Venus orbited the Sun, which was a crucial support for the Copernican heliocentric model and a challenge to the geocentric Ptolemaic model.

Step-by-step explanation:

Galileo's observations of the phases of Venus were evidence supporting the Copernican theory that Venus orbited the Sun. Through his use of the telescope, Galileo found that Venus exhibited a full range of phases, similar to those of the Moon. This observation was inconsistent with the Ptolemaic model, which suggested Venus circled Earth, and could not account for the phases in the order observed by Galileo. Instead, these phases indicated that Venus must revolve around the Sun, allowing us to see different parts of its daylight side at different times. Thus, Galileo's observations were instrumental in challenging the long-held geocentric view that placed Earth at the center of the universe.