Solution By Steps

Step 1: Identify the Moon’s Phases

The period when the Moon appears to be getting smaller in size is known as the waning phase.

Step 2: Understand the Waning Phase

During the waning phase, the illuminated portion of the Moon visible from Earth decreases, making it appear to shrink in size.

Step 3: Differentiate from the Waxing Phase

This is opposite to the waxing phase, where the Moon appears to be getting larger in size as the illuminated portion increases.

Final Answer

Waning Phase

Key Concept

Moon Phases

Key Concept Explanation

Moon phases describe the changing appearance of the Moon as viewed from Earth due to its position relative to the Sun. The waning phase is when the Moon appears to be getting smaller in size as the illuminated portion visible from Earth decreases.