Barrow, Alaska, also known as UtqiaÄávik, the northernmost city in the United States, bids farewell to the sun on November 18, 2024. THE SCIENCE BEHIND THE DARKNESS The polar night occurs because of the Earth's axial tilt, which causes areas near the poles to experience extended periods of darkness during winter. In UtqiaÄávik, Alaska, this twilight period lasts approximately three …