twilight

(redirected from Astronomical twilight)
Also found in: Dictionary, Thesaurus, Encyclopedia, Wikipedia.
Related to Astronomical twilight: astronomical year

twi·light

(twī'līt),
1. Figuratively, a faint light.
2. Pertaining to faint or indistinct mental perception, as in twilight state.
[A.S. twi-, two]
References in periodicals archive ?
Casual observers may see no difference between night and astronomical twilight, but astronomers know it's the best time for using telescopes, especially for viewing distant galaxies.
But by the end of the month this has increased to 11 hours with astronomical twilight arriving later and later.
e) road lighting control is carried out by means of sensors and timers astronomical twilight
Astronomical twilight ends when the Sun is 18[degrees] below the horizon.
Uranus, in Pisces, transits the meridian at the end of astronomical twilight as 2015 ends.
So much so that the skies never get truly dark at this time of year and the sky remains in an astronomical twilight for what little of the night we have.
Mercury reaches greatest western elongation on the 16th, when it rises at the very start of astronomical twilight.
Astronomical twilight is the period between 'civil' twilight and the time when the Sun is 16[degrees] below the horizon.

Full browser ?