When Earth, the Moon, and the Sun form a right angle, the tidal range is smallest. What is this called?

When Earth, the Moon, and the Sun form a right angle, the tidal range is smallest. What is this called?

• A. Neap tide
• B. Spring tide
• C. High tide
• D. Tidal range

Answer: (A)

Neap tide is at play here. When the Sun, Moon, and Earth form a right angle (the Moon is at first or third quarter), the solar and lunar tides pull in directions that partially cancel each other. That cancellation reduces the overall height difference between high and low tides, so the tidal range is smallest. For contrast, think of spring tides, which occur during new or full Moon when the Sun and Moon are aligned with Earth; their tides reinforce each other and create the largest tidal range. High tide and tidal range describe the water levels themselves or the difference between them, but the phase described by a right-angle geometry specifically names a neap tide.

Neap tide is at play here. When the Sun, Moon, and Earth form a right angle (the Moon is at first or third quarter), the solar and lunar tides pull in directions that partially cancel each other. That cancellation reduces the overall height difference between high and low tides, so the tidal range is smallest.

For contrast, think of spring tides, which occur during new or full Moon when the Sun and Moon are aligned with Earth; their tides reinforce each other and create the largest tidal range. High tide and tidal range describe the water levels themselves or the difference between them, but the phase described by a right-angle geometry specifically names a neap tide.