civil twilight


Also found in: Encyclopedia, Wikipedia.

civil twilight

References in periodicals archive ?
Daytime was defined as the time from civil twilight at dawn to civil twilight at dusk, and nighttime was defined as the time from civil twilight in the evening to civil twilight in the morning of the next day.
twilight Civil twilight is the period from sunset to the time that the Sun is 6[degrees] below the horizon.
From there, I started exploring the stages of a sunset: the Golden Hour, the Civil Twilight, the Blue Hour, and the Nautical Twilight.
The duration of nautical twilight--a phase of twilight preceding civil twilight, when artificial lighting is necessary for humans to see acceptably on moonless mornings, but the horizon is still distinct--over the same time period ranged between 27 and 33 min, with an average of 29:20 (min:s).
He continued to pursue this concept, even while serving from 2007 to 201 2 as chief executive officer of Civil Twilight, a San Francisco-based, cross-disciplinary design collective that he co-founded.
The Pilot/Controller Glossary defines "night" as the time between the end of evening civil twilight and the beginning of morning civil twilight.
Drones can only conduct operations in daylight or civil twilight with appropriate anti-collision lighting and can only have a maximum speed of 100 mph.
twilight and civil twilight, the slope of the landscape is
At the start of the period Venus is 4[degrees] high at the end of civil twilight whilst by the end of the period, as the angle of the ecliptic increases, the planet is 11[degrees] high in the same twilight conditions.
[paragraph] That moment is called "civil twilight." It occurs every morning, and again each evening.
Introducing us to the pitch-black island of Sark, and groups such as Civil Twilight (designer of streetlights that shut off under moonlight) and Starlight Reserves (which considers freedom from light pollution a basic right), he makes a solid case for hitting the national dimmer switch.
Civil Twilight is when the less than one degree due north of fourth magnitude star Upsilon Geminorum.