what is the earth's tilt on its axis
At an obliquity of 0 degrees, the two axes point in the same direction; i.e., the rotational axis is perpendicular to the orbital plane. Earth's obliquity oscillates between 22.1 and 24.5 degrees on a 41,000-year cycle; Earth's mean obliquity is currently 23 ° 26 ′ 12.6" (or 23.43684 °) and decreasing.