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
On a sundial, what is the part that casts the shadow called?
AnswerThe gnomon
The gnomon is the raised edge or rod whose shadow points to the hour on a sundial.
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.
Roughly how long does sunlight take to reach Earth?
AnswerAbout 8 minutes
Light travels about 150 million km from the Sun in roughly 8 minutes and 20 seconds.
Expert level
Who built the first pendulum clock, in 1656?
AnswerChristiaan Huygens
Galileo studied pendulums, but Dutch scientist Christiaan Huygens built the first pendulum clock in 1656.
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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