Twilight is the time between dawn and sunrise or between sunset and dusk, during which sunlight scattering in the upper atmosphere illuminates the lower atmosphere, and the surface of the earth is neither completely lit nor completely dark. The sun itself is not directly visible because it is below the horizon. Twilight is technically defined as the periods between sunset and sunrise during which there is natural light provided by the upper atmosphere, which receives direct sunlight and scatters part of it towards the earth's surface. As astronomers of course we like it as dark as we can get it, with the charts below you should always be aware of the coming light schedule.

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Moon Rise
& Set Chart
The Moon is majestic, it's big and bright and fun to take pictures of. However if you are not wanting to do just that, our lovly moon tends to get in the way. To astronomers that bright ball of a moon can spoil an otherwise perfect observing night. Use these charts to stay on top of it!
Sun Rise and Set Chart These Sun rise and set charts are the best there is. We all want to know when that big orange is going to go down so we can start our observations. At the other end of the night, or morning, you will want to know when your great night is going to come to an end.
Astronomical Twilight Chart Astronomical twilight is the time when the center of the sun is between 12° and 18° below the horizon. From the end of astronomical twilight in the evening to the beginning of astronomical twilight in the morning, the sky is dark enough for all astronomical observations.
Nautical Twilight Chart Nautical twilight is the time when the center of the sun is between 6° and 12° below the horizon. In general, nautical twilight ends when navigation via the horizon at sea is no longer possible.
Civil Twilight Chart Morning civil twilight begins when the geometric center of the sun is 6° below the horizon (civil dawn) and ends at sunrise. Evening civil twilight begins at sunset and ends when the geometric center of the sun reaches 6° below the horizon (civil dusk).


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