Ancient authorities like Aristotle and the
Roman astronomer Ptolemy had championed this viewpoint,
and the notion also coincided with the Catholic
Church’s view of the universe, which placed mankind,
God’s principal creation, at the center of the cosmos.
Buttressed by common sense, the ancient philosophers,
and the church, the geocentric model of the universe
seemed secure in its authority. The Ptolemaic theory,
however, was not impervious to attack. In the 16th century,
astronomers strained to make modern observations
fit Ptolemy’s geocentric model of the universe.