How many seconds are in one hour?
Answer3,600
An hour has 60 minutes of 60 seconds each: 60 x 60 = 3,600 seconds.
Science · Facts & stats
Time facts & stats
7 fact-checked facts about time and timekeeping, each with the reason behind it. 5 more are in today's round and join this page after it closes.
The basics
How many days are in a leap year?
Answer366
A leap year adds February 29, giving 366 days instead of 365.
Going deeper
What does 'a.m.' stand for?
AnswerAnte meridiem, before midday
a.m. is Latin 'ante meridiem', before midday; p.m. is 'post meridiem', after midday.
Why are there 60 minutes in an hour?
AnswerIt comes from the ancient Babylonian base-60 counting system
The Babylonians counted in base 60, and their system survives in how we divide hours and circles.
The International Date Line runs mainly through which ocean?
AnswerPacific Ocean
The date line zigzags through the Pacific at roughly 180° longitude, where the calendar date changes.
Expert level
Under Gregorian calendar rules, which of these years is a leap year?
Answer2000
Century years are leap years only if divisible by 400, so 2000 is a leap year but 1900 and 2100 are not.
How long does Earth take to rotate once relative to the distant stars (a sidereal day)?
AnswerAbout 23 hours 56 minutes
A sidereal day is about 4 minutes shorter than a solar day, because Earth also moves along its orbit.
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