Twice per year, when day and night are equal in length, the Sun is at one of two positions in the sky known as equinoxes. These points are the intersections of which two planes in the sky?
A) celestial equator and ecliptic
B) celestial meridian and celestial equator
C) ecliptic and celestial meridian
D) ecliptic and arctic circle

Question

Quizplus · Accepted Answer

The equinoxes occur at the points where the celestial equator (an extension of Earth's equator into space) intersects with the ecliptic (the apparent path of the Sun across the sky over the course of a year). This intersection happens twice a year, leading to days and nights of equal length.

Twice Per Year, When Day and Night Are Equal in Length