what is the earth's tilt on its axis
Axial tilt 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[2] on a 41,000-year cycle; Earth's mean obliquity is currently 23°26′12.6″ (or 23.43684°) and decreasing.
Earth's rotation Among the ancient Greeks, several of the Pythagorean school believed in the rotation of the earth rather than the apparent diurnal rotation of the heavens. Perhaps the first was Philolaus (470â€“385 BCE), though his system was complicated, including a counter-earth rotating daily about a central fire.[3]