Earth Systems Glossary
Axis imaginary line that extends from the Earth's North to the South Pole (tilted at 23.5 degrees)
Equator an imaginary line that divides the Earth into the northern and southern hemispheres (half-spheres)
Gravity the force of attraction between any two masses
Lunar phases changes in the sunlit part of the moon as it revolves around the Earth
Moon a natural satellite of a planet, it is always smaller than its planet.
Neap tide a tide that occurs when the difference between high and low tide is least when the sun, Earth and moon form a right angle
Orbit the path travelled by Earth around the sun
Planet spherical "cool" object orbiting a star
Satellite any object in a regular orbit around another larger body
Seasons spring, summer, autumn and winter; caused by the tilt of the Earth's axis and its revolution around the sun
Spring tide very high and low tides occur at the time of the new moon or the full moon (when the sun, Earth and moon are aligned)
Tides periodic rise and fall of the ocean caused by the Earth’s rotation and the gravitational pull of the moon (and sun)
Equator an imaginary line that divides the Earth into the northern and southern hemispheres (half-spheres)
Gravity the force of attraction between any two masses
Lunar phases changes in the sunlit part of the moon as it revolves around the Earth
Moon a natural satellite of a planet, it is always smaller than its planet.
Neap tide a tide that occurs when the difference between high and low tide is least when the sun, Earth and moon form a right angle
Orbit the path travelled by Earth around the sun
Planet spherical "cool" object orbiting a star
Satellite any object in a regular orbit around another larger body
Seasons spring, summer, autumn and winter; caused by the tilt of the Earth's axis and its revolution around the sun
Spring tide very high and low tides occur at the time of the new moon or the full moon (when the sun, Earth and moon are aligned)
Tides periodic rise and fall of the ocean caused by the Earth’s rotation and the gravitational pull of the moon (and sun)