Question

The following diagram shows various positions of the moon in its orbit around Earth. The image of the moon shows its phase as seen from Earth. Earth is shown with a bigger circle on the right is a bigger circle labeled as Sun. Two lunar phases are shown. First quarter is shown above Earth and the Third Quarter below Earth. Arrows are drawn in the counter clockwise direction. Position A is marked on the left of Earth, position B is marked halfway between position A and the Third Quarter. Position C is marked on the right of Earth, position D is marked halfway between position C and the First Quarter. In which position will three-fourths of the illuminated side of the moon be visible from Earth? A B C D

Answer 1

The moon is transitioning from full to half moon phase at point B. At B, the moon will be in gibbous phase, with three-quarters of the lighted side visible.

When the moon is at position B, three-quarters of the lit side of the moon is visible from Earth.

Every day, we witness new forms of the moon as it rotates around the Earth. Moon phases occur when various portions of the moon's illuminated side are seen from Earth.

There is a full moon phase at position A, according to the diagram.

Since the lit side does not face the earth at point C, a new phase begins.

The moon is transitioning from new moon to half moon in location D, therefore it will be crescent phase.

Answer 2

D. If you have scratch paper and draw it out, it would greatly help you. A different way would be to visualize it in your head. Behind the Earth is Full moon, in front is new moon, above/below is half/gibbous. To the right of below is 3/4. To the left of below is 1/4. To the right of above is also 3/4. To the left of above is 1/4.