Which of the following observations provided the most direct challenge to the geocentric model of solar system orbits?
A) the topography of the Moon
B) phases of Venus
C) sunspots
D) supernovae

Question

Quizplus · Accepted Answer

The phases of Venus directly challenged the geocentric model because they showed that Venus was circling the Sun, not the Earth. As Venus orbited the Sun, we observed it going through phases just like the Moon does. This was only possible if Venus was on a different orbit than Earth, which contradicts the geocentric model where all planets orbit the Earth. The other observations listed are not direct challenges to the geocentric model.

Which of the Following Observations Provided the Most Direct Challenge