Question

What caused the Earth's axis to become tilted? *

Answer 1

This tilt was caused by a collision with an Earth-sized planet billions of years ago; called Theia.

Answer 2

long ago, when Earth was young, it is thought that something big hit Earth and knocked it off-kilter. So instead of rotating with its axis straight up and down, it leans over a bit. By the way, that big thing that hit Earth is called Theia.

Step-by-step explanation: