Продолжительность сумерек в Тайбэй
На широте Тайбэй 25.0° продолжительность сумерек dramatically varies by season. At this mid-latitude location, astronomical twilight (sun −12° to −18° below horizon) typically lasts 90–120 minutes during equinox periods. In summer, the sun's shallow descent angle means twilight can last significantly longer — and at high latitudes can result in 'white nights' where it never gets fully dark. This seasonal variation is what makes Тайбэй's dark-sky window so different month to month.
Taipei sits near the Tropic of Cancer at 25°N — the latitude where the Sun reaches exactly 90° altitude at the June solstice, casting no shadow at solar noon. The city's National Museum of Natural Science operates a dedicated solar observatory that tracks the Sun's zenith passage, and the Tropic of Cancer landmark in Chiayi draws thousands of visitors each June to witness the 'no shadow day' phenomenon.
Справочник сумерек NOAA