Sentences with phrase «civil twilight»

Please note that the above definition of civil twilight does not apply in Alaska.

However, if the sUAS has appropriate anti-collision lighting visible for at least 3 statute miles, the sUAS may operate during civil twilight hours.

In Alaska, civil twilight is defined in the Air Almanac.

Civil twilight hours are defined as the period of time that begins 30 minutes before official sunrise and 30 minutes after official sunset.

Civil twilight — here Wikipedia comes to our aid — has a technical definition, as do the others, and a more functional definition as well.

In the morning before the beginning of civil twilight and in the evening after the end of civil twilight, artificial illumination is normally required to carry on ordinary outdoor activities.

This is the limit at which twilight illumination is sufficient, under good weather conditions, for terrestrial objects to be clearly distinguished; at the beginning of morning civil twilight, or end of evening civil twilight, the horizon is clearly defined and the brightest stars are visible under good atmospheric conditions in the absence of moonlight or other illumination.

Civil Twilight Viewing Thursday, September 22 - Fall Equinox 6:30 pm Music Performance by Dan Riley from 6:52 - 7:19 pm Free and open to the public Held in conjunction with Karen Lee Williams, Remote Sensing Civil twilight is the period right after sunset when there is enough diffuse light to clearly see your surroundings.

If you include civil twilight, Alaska gets 40 minutes more light on average than the rest of the country.