Sun, Earth, and Moon Relationships Set #1

Vocabulary flashcards covering key definitions and relationships between the Sun, Earth, and Moon.

tilt of the earth

the angle at which the Earth is tilted on its axis, approximately 23.5 degrees, affecting seasons and climate.

axis

imaginary line that passes from north to south through the earth or any planet, about which it rotates.

rotation

to spin on a center axis; results in day and night

revolution

to go around the sun; results in seasons due to Earth’s tilt

summer solstice

longest day of the year; most direct sunlight; June 21st

winter solstice

shortest day of the year; most indirect sunlight; Dec 21st

spring equinox

equal hours of day and night in the spring; March 21st

autumnal equinox

equal hours of day and night in the autumn (fall); Sept 22

solar eclipse

occurs when the Moon passes between the Earth and the Sun, blocking the Sun's light either partially or completely from reaching the Earth.

lunar eclipse

occurs when the Earth passes between the Sun and the Moon, casting a shadow on the Moon.

umbra

the fully shaded inner region of a shadow during an eclipse.

penumbra

the partially shaded outer region of a shadow during an eclipse.

total eclipse

An event where the light from the Sun or Moon is entirely blocked from view, seen from inside the umbra

partial eclipse

An event where part of the Sun or Moon is obscured, resulting in a portion of light being blocked, seen from inside the penumbra

annular eclipse

A solar eclipse where the Moon is too far away in its orbit to completely cover the Sun, leaving a thin "ring of fire" visible around the Sun. This occurs when the Moon is in the apogee position during the eclipse.