Unit 2 Lesson 1 Key Terms

The spin of a body on its axis.

• rotation

• day

• revolution

• year

The time required for Earth to rotate once on its axis.

• year

• day

• season

• revolution

The motion of a body that travels around another body in space; one complete trip along an orbit.

• rotation

• revolution

• season

• day

The time required for Earth to orbit once around the sun.

• day

• year

• season

• equinox

A division of the year that is characterized by reoccurring weather conditions, and determined by both Earth's tilt relative to the sun and Earth's position in its orbit around the sun.

• season

• year

• day

• equinox

The moment when the sun appears to cross the celestial equator.

• equinox

• solstice

• day

• year

The point at which the sun is as far north or as far south of the equator as possible.

• equinox

• solstice

• day

• year