A day is the time period of a full rotation of the Earth with respect to the Sun. On average, this is 24 hours (86,400 seconds). As a day passes at a given location it experiences morning, afternoon, evening, and night. This daily cycle drives circadian rhythms in many organisms, which are vital to many life processes.
AI overview
A day is the 24-hour period it takes for Earth to complete one full rotation relative to the Sun, during which a location experiences morning, afternoon, evening, and night. This daily cycle is important because it drives circadian rhythms in many organisms, which are essential to vital life processes.
AI-generated from the Wikipedia summary — may contain errors.
Wikidata facts
- Subclass of
- time interval
- Part of
- week
- Has part
- sunrise
- Image
- GreenwUhrWelt.jpg
Show 8 more facts
- P910
- Category:Days
- P460
- nychthemeron
- P2670
- time of day
Article
19 sectionsContents
- Etymology
- Definitions
- Apparent and mean solar day
- Civil day
- Sidereal day{{anchor|Extraterrestrial bodies}}
- In the International System of Units
- In decimal and metric time
- Other definitions
- Variations in length
- Geological day lengths
- Boundaries
- Parts
- Daytime
- Twilight
- Night
- In other cultures
- See also
- References
- External links
A day is the time period of a full rotation of the Earth with respect to the Sun. On average, this is 24 hours (86,400 seconds). As a day passes at a given location it experiences morning, afternoon, evening, and night. This daily cycle drives circadian rhythms in many organisms, which are vital to many life processes.
A collection of sequential days is organized into calendars as dates, almost always into weeks, months and years. A solar calendar organizes dates based on the Sun's annual cycle, giving consistent start dates for the four seasons from year to year. A lunar calendar organizes dates based on the Moon's lunar phase.