tengelyferdeség

Tengelyferdeség, also known as axial tilt or obliquity, refers to the angle between an astronomical body's rotational axis and its orbital axis, or more commonly, its rotational axis and the perpendicular to its orbital plane. This tilt is a fundamental characteristic of planets, moons, and other celestial objects.

The Earth's axial tilt is approximately 23.5 degrees. This tilt is the primary cause of the seasons. As the Earth orbits the Sun, different hemispheres are tilted towards or away from the Sun, leading to variations in the amount of direct sunlight received. When the Northern Hemisphere is tilted towards the Sun, it experiences summer, while the Southern Hemisphere experiences winter. Six months later, the situation is reversed.

The magnitude of axial tilt can vary significantly between celestial bodies. For instance, Uranus has an extreme axial tilt of about 98 degrees, essentially orbiting the Sun on its side. This results in very unusual seasonal patterns. In contrast, Venus has a very small axial tilt, close to zero degrees, meaning it experiences very little seasonal variation. Mercury has a tilt of approximately 0.01 degrees.

Over long periods, axial tilt can also change. These variations are known as Milankovitch cycles and can influence long-term climate changes on Earth. The stability of an object's axial tilt is influenced by gravitational interactions with other celestial bodies, particularly large moons or neighboring planets.