The Earth rotates on its axis approximately once every 24 hours relative to the Sun (solar day), but more precisely once every 23 hours, 56 minutes, and 4 seconds relative to distant stars (sidereal day)
. At the equator, this rotation translates to a tangential speed of about 1,670 kilometers per hour (around 1,000 miles per hour)
. This speed decreases as you move towards the poles because the circumference of the Earth at higher latitudes is smaller; the speed at any given latitude can be approximated by multiplying the equatorial speed by the cosine of the latitude
. In summary:
- Rotation period: about 24 hours (solar day), or 23h 56m 4s (sidereal day)
- Speed at equator: roughly 1,670 km/h (1,000 mph)
- Speed decreases towards poles, becoming nearly zero at the poles
This rotation speed is why points on the equator travel the fastest linear distance in a day, while poles effectively rotate in place.
