solar day
Noon to noon
A solar day is the time it takes for the sun to return to the same position in the sky—roughly 24 hours.
This is the basis for our standard day, measured from noon to noon or midnight to midnight.
It varies slightly throughout the year due to Earth's elliptical orbit, so clocks use the average: the mean solar day.
Morning light's arrival
- sunsetDay yielding to darkness
- sunlightRadiance from our star
- daylightSun's natural glow
- rotationTurning on an axis
Earth · axial tilt · equinox · zenith · meridian · declination · heliocentric · sundial
Specific day or outing
- 24 hoursOne day's duration
- midnightTwelve o'clock at night
- noonDay's exact middle
- GregorianNamed for a pope
Julian · time zone · local time · standard time · UTC · atomic clock · clock · timekeeping
sunrise
Morning light's arrival
rotation · Earth · axial tilt · equinox · zenith · meridian · declination · heliocentric · sundial · ecliptic
date
Specific day or outing
Gregorian · Julian · time zone · local time · standard time · UTC · atomic clock · clock · timekeeping · epoch
dawn
Day's first glow
afternoon · sunset · dusk · twilight · daylight · nightfall · daybreak · sunup · golden hour · blue hour