The duration of the twilight period between dawn and sunrise varies greatly depending on the observer's latitude, from a few minutes in equatorial regions to many hours in polar regions. Dawn may easily be determined by observing a thread. When the color of a thread can be determined, changing from black to the thread's distinctive color, the 'crack of dawn' has occurred. This same measure of ambient light can be used to determine, conversely, the instant of dusk.
Burlington to Open at Gateway Centre: A Win for Rogers Park
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Rogers Park residents have something new to look forward to: *Burlington*
is joining the Gateway Centre lineup at *Howard Street and Clark Street*,
bring...
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