On June 21st, which area experiences 24 hours of daylight?

On June 21st, which area experiences 24 hours of daylight?

• A. Arctic Circle
• B. Antarctic Circle
• C. Equator
• D. Tropic of Cancer

Answer: (A)

The main idea is how Earth's tilt creates days of constant daylight at polar latitudes during solstices. Around June 21, the Northern Hemisphere is tilted toward the Sun, so regions north of about 66.5° latitude—the Arctic Circle—receive sunlight all day long. This is the phenomenon known as the midnight sun, where the Sun doesn’t set for 24 hours at those high latitudes. The Arctic Circle sits well above the equator, where day and night alternate normally, roughly 12 hours each day. The Tropic of Cancer, at about 23.5°N, experiences very long days in June but still has regular sunset, so it does not get 24 hours of daylight. The Antarctic Circle would have 24 hours of daylight around its summer solstice in December, not June, because it’s in the opposite hemisphere.

The main idea is how Earth's tilt creates days of constant daylight at polar latitudes during solstices. Around June 21, the Northern Hemisphere is tilted toward the Sun, so regions north of about 66.5° latitude—the Arctic Circle—receive sunlight all day long. This is the phenomenon known as the midnight sun, where the Sun doesn’t set for 24 hours at those high latitudes.

The Arctic Circle sits well above the equator, where day and night alternate normally, roughly 12 hours each day. The Tropic of Cancer, at about 23.5°N, experiences very long days in June but still has regular sunset, so it does not get 24 hours of daylight. The Antarctic Circle would have 24 hours of daylight around its summer solstice in December, not June, because it’s in the opposite hemisphere.