Answer:
Because of the way the Sun formed
Explanation:
The original cloud was spinning, and this spin caused it to flatten out into a disk shape due contracting as gravity pulled its parts toward the center. This dust cloud rotated slowly at first but sped up as it contracted, in much the same way that a figure skater spins more quickly when she pulls her arms closer to her body. (This law of physics is known as angular momentum.) The faster rotation flattened the cloud, with the Sun at the center and planets forming within that plane
