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Landers, California at astronomical dusk (20-second exposure) Desert Dusk.jpg
Landers, California at astronomical dusk (20-second exposure)

Dusk occurs at the darkest stage of twilight, or at the very end of astronomical twilight after sunset and just before nightfall. [1] At predusk, during early to intermediate stages of twilight, enough light in the sky under clear conditions may occur to read outdoors without artificial illumination; however, at the end of civil twilight (when Earth rotates to a point at which the center of the Sun's disk is 6° below the local horizon), such lighting is required to read outside. [2] The term dusk usually refers to astronomical dusk, or the darkest part of twilight before night begins.


Technical definitions

Civil, nautical, and astronomical twilight. Dusk is the darkest part of evening twilight. Twilight subcategories.svg
Civil, nautical, and astronomical twilight. Dusk is the darkest part of evening twilight.

The time of dusk is the moment at the very end of astronomical twilight, just before the minimum brightness of the night sky sets in, or may be thought of as the darkest part of evening twilight. [4] However, technically, the three stages of dusk are as follows:


Dusk can be used to create an ominous tone and has been used as a title for many projects. One instance of this is the 2018 first person shooter Dusk (video game) by New Blood Interactive whose setting is in a similar lighting as the actual time of day.

See also

Related Research Articles

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  1. The Random House College Dictionary, "dusk".
  2. 1 2 "Rise, Set, and Twilight Definitions". USNO.
  3. Van Flandern, T.; K. Pulkkinen (1980). "Low precision formulae for planetary positions". Astrophysical Journal Supplement Series. 31 (3): 391. Bibcode:1979ApJS...41..391V. doi:10.1086/190623.
  4. "Full definition of Dusk".
  5. "Dusk – Definition and Meaning". www.timeanddate.com.