Aug 24, 2017 · 1 min read
> there are only 23 hours, 56 minutes and 4 seconds in an actual day
That’s how long it takes the Earth to rotate relative to “the fixed stars”, a.k.a. a sidereal day. The standard solar day, relative to the sun, really is 24 hours. Calling a sidereal day an actual day is not very useful. For everyone but astronomers, 24 hours matches what they observe.