360/Historical Note

Historical Note on $360$ (Three Hundred and Sixty)

There are $360$ degrees in a full angle.

This appears to have been first done by Hipparchus of Nicaea.

$360$ is very approximately equal to the number of days in a year, which goes some way towards explaining this division of the circle.

Each of the signs of the Zodiac were divided into $30$ degrees, each one corresponding to approximately one day's travel of the sun around the ecliptic.

Sources

• 1986: David Wells: Curious and Interesting Numbers ... (previous) ... (next): $360$
• 1997: David Wells: Curious and Interesting Numbers (2nd ed.) ... (previous) ... (next): $360$