Of all the planets in the solar system, Uranus is probably the oddest. A cool blue planet, it rotates on its side! The faint ring system around the planet gives testament to the fact, and makes the sight even more interesting. It really is quite baffling, since such a tilt is unmatched by the other planets. However, cosmologists today have a fair estimate as to what caused this tilt and why Uranus was the unlucky one.
The tilt of planets is quite a normal thing, and occurs due to gravitational forces. The Earth has a tilt of 23 degrees. Uranus, however, is tilted at a whopping 98 degrees. The initial explanation was that a violent impact caused Uranus to tilt. Constructing a scenario for single-impact, scientists found that had it happened, Uranus’ moons would have shown retrograde motion i.e. spinning opposite to the planet’s motion.
The lack of such evidence pushed them towards the plausibility of multiple impacts. They also postulated that these impacts occurred in the early days of the Solar System. The initial tilt might not have been so pronounced, but over time gravitational effects would have made it so visible. A side explanation also suggests that after the initial impact, the larger of the Uranus’s moons would have â€˜tugged’ on the planet and caused the tilt.
While a definitive explanation is still to come, the foreseeable future does hold the answer. With new space dating techniques being used to reconstruct the past, we will eventually find the answer to this mystery. For now, we know that a series of violent impacts hit Uranus in the early stages of the Solar System, and then gravity did the rest.