Uranus and Neptune’s differences might boil down to collisions
Scientists assume Uranus and Neptune had evolved similarly since they have the same masses, sizes, and distance from the sun. But there are also many variations between the two planets, suggesting that they may not be as identical as they seem at first look.
Now, a team of researchers has used computer models to demonstrate that collisions with massive, rocky bodies could have contributed to the differing history of the two planets, potentially explaining their differences.
The most evident difference between the planets, maybe, is their angles of rotation. The planet Uranus ‘ spin is rotated by around 98 degrees as opposed to its orbital plane. Neptune and most other planets of the solar system meanwhile have rotations more or less consistent with their orbits. Another difference is that Neptune appears to have some internal heat source warming it up, which is not the case for Uranus.
According to earlier studies, massive impacts may explain Uranus’ tilted spin, while also explaining other variations among the two planets. So the University of Zurich’s Christian Reinhardt and other scientists decided to examine whether the state-of-the-art 3Dimension simulations today will support those concepts.
The researchers found that if Neptune had a head-on collision in its past with some massive rocky object, it could have put some more energy deep inside the planet, which over time has slowly exploded out as heat. This, they imagine, might be the cause of the extra warmth this radiates from the interior of Neptune.
For Uranus, the models show that the tilt of the planet and the peculiar orbital properties of its moons could be due to a grazing or oblique impact from another rocky body. Researchers believe that the Uranus moons were probably formed from a debris disk that once was around the planet, and the new models indicate that such a debris disk could have been the byproduct of a glancing blow.