When do neap tides occur?

• A. The Sun is rising
• B. Sun and Moon are perpendicular
• C. The Moon is full
• D. Sun and Moon are aligned

Answer: (B)

Neap tides happen when the Sun and Moon form a right angle with Earth, so their gravitational pulls partially cancel each other. The Moon’s gravity is the primary driver of tides, and the Sun’s gravity adds to it. When they are lined up (new Moon or full Moon), their pulls reinforce each other, producing larger tides—these are spring tides. When they are perpendicular, their pulls oppose enough to reduce the tidal range, leading to neap tides. This pattern occurs around the first and third quarters of the Moon.

The Sun rising is a daily event and doesn’t set up this tidal pattern. A full Moon or the Sun and Moon being aligned describes configurations that amplify tides (spring tides), not neap tides.