Celestial Motions and Models

A collection of flashcards covering key vocabulary and concepts relating to celestial motions and models.

Geocentric Model

An Earth-centered model of the universe where all celestial objects revolve around the Earth.

Heliocentric Model

A sun-centered model of the universe proposed by Copernicus, stating that the Earth and other planets orbit the Sun.

Celestial Sphere

The visible portion of the sky that celestial objects appear to travel on.

Apparent Motions

The way celestial objects appear to move across the sky due to Earth's rotation and revolution.

Coriolis Effect

The apparent curvature of the winds and ocean currents caused by Earth's rotation.

Foucault Pendulum

A device that demonstrates Earth's rotation by showing a slow change in direction as it swings.

Altitude

The angle from the horizon up to a celestial object.

Zenith

The highest point on the celestial sphere directly over the observer.

Horizon

The edge of the visible portion of the celestial sphere.

Rotation

The spinning of Earth on its axis, which occurs at a rate of 15° per hour.

Revolution

The motion of Earth traveling around the Sun at a rate of 1° per day.

Aphelion

The point in an orbit where the celestial object is farthest from the Sun.

Perihelion

The point in an orbit where the celestial object is closest to the Sun.

Celestial Objects

Natural objects that can be seen in the sky, including the sun, moon, stars, and planets.