Science / Weather / Astronomical Twilight: The time after nautical twilight has commenced and when the sky is dark enough, away from the sun's location, to allow astronomical work to proceed. It ends when the center of the sun is 18?° below the horizon.
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Twilight Adjective Synonyms: dusk, sunset, gloaming, sundown, half-light, crepuscule or crepuscle
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Science / Weather / Twilight: Often called dusk, it is the evening period of waning light from the time of sunset to dark. The time of increasing light in the morning is called dawn. Twilight ends in the evening or begins in the m MORE
Entertainment / Golf / Twilight Rate: A discounted green fee based on the fact that a limited number of holes may be completed due to darkness MORE
Technology / Aviation / Twilight Zone: Long before Rod Serling's tv series was this consumer-lever definition for a glitch in the ADCOCK RANGE, officially called a Bi-Signal Zone. It was a portion of the overlapping area of a beam where th MORE
Science / Weather / Nautical Twilight: The time after civil twilight, when the brighter stars used for celestial navigation have appeared and the horizon may still be seen. It ends when the center of the sun is 12 degrees below the horizon MORE
Science / Tides and Currents / Lowest Astronomical Tide: As defined by the International Hydrographic Organization, the lowest tide level that can be predicted to occur under average meteorological conditions and under any combination of astronomical condit MORE
Science / Weather / Astronomical Twilight: The time after nautical twilight has commenced and when the sky is dark enough, away from the sun's location, to allow astronomical work to proceed. It ends when the center of the sun is 18?° below t MORE