Why do most of the planets in our Solar System orbit on relatively the same 2D

 

The planets in our Solar System orbit the Sun in roughly the same plane, a configuration known as the "ecliptic plane." This characteristic alignment can be attributed to the way the Solar System formed from a rotating, flattened disk of gas and dust.

The formation of the Solar System is thought to have begun with the gravitational collapse of a large molecular cloud. As this cloud collapsed, it started to spin, forming a rotating disk. The majority of the material in this disk eventually accreted to form the Sun, while the remaining material in the disk began to clump together to form the planets.

Conservation of angular momentum played a crucial role in shaping the Solar System. As the material in the rotating disk came together to form the Sun and planets, the conservation of angular momentum caused the spinning disk to flatten out into a disk-like structure. This disk was the birthplace of the planets.

The planets then formed from the material in this disk, and their orbits ended up lying along the plane of this original disk due to the conservation of angular momentum. Over time, gravitational interactions between the planets may have caused some variations in their orbits, but the overall pattern of planets orbiting in a relatively flat plane has been preserved.

In summary, the common orbital plane of the planets in our Solar System is a consequence of the way the Solar System formed from a spinning, flattened disk of gas and dust.