What was the primary cause of the perturbations in Uranus's orbit?

The primary cause of the perturbations in Uranus's orbit was the gravitational influence of a nearby planet, specifically Neptune. When astronomers observed Uranus's orbit, they noted discrepancies from the predictions based on Newtonian mechanics. These inconsistencies led to the hypothesis that another massive body was exerting a gravitational pull on Uranus, disrupting its expected path.

This culminated in the discovery of Neptune in 1846, when astronomers were able to calculate its position based on the observed irregularities in Uranus’s motion. The gravitational interactions among celestial bodies are fundamental concepts in physics, particularly in the study of orbital mechanics, illustrating how the presence of unobserved or unseen objects can have significant effects on other bodies in space. Thus, the influence of Neptune on Uranus's orbit is a prime example of how understanding gravitational forces can lead to major astronomical discoveries.