SOLAR SYSTEM

Detailed explanation-1: -2.3. 1 Introduction. The solar nebula was the rotating, flattened disk of gas and dust from which the solar system originated  4.6 Ga ago (Figure 1).

Detailed explanation-2: -Why did the solar nebula flatten into a disk? The force of gravity from the planets pulled the material downward into a flat disk. It flattened as a natural consequence of collisions between particles in the spinning nebula, changing random motions into more orderly ones.

Detailed explanation-3: -That shape, they determined, is croissant-like: a curving central bulge with two jets curling away from it. “Because the pick-up ions dominate the thermodynamics, everything is very spherical, ‘’ Opher said. “But because they leave the system very quickly beyond the termination shock, the whole heliosphere deflates."

Detailed explanation-4: -Most likely the next step was that the nebula flattened into a disk called the Protoplanetary Disk; planets eventually formed from and in this disk.

Detailed explanation-5: -Collisions between particles in the cloud caused it to flatten into a disk. particles in cloud gradually reduce random motions.