When we see a half-moon,the position of the Sun is
A)almost directly behind the Moon.
B)almost directly behind the Earth.
C)at right angles to a line from Earth to the Moon.
D)about 45° from a line from Earth to the Moon.

Question

Quizplus · Accepted Answer

When we see a half-moon, the position of the Sun is at right angles to a line from Earth to the Moon. This means that the Sun, Earth, and Moon form a right triangle, with the Earth at the right angle. The side of the triangle formed by the Sun and Moon is where the illuminated portion of the Moon can be seen, giving us a half-moon.

When We See a Half-Moon,the Position of the Sun Is