Longitude of the Sun

Overview

This is the approximate longitude of the sun, the distance in degrees the Earth has traveled along its orbit since the last Northward Equinox.

Info

The longitude of the sun is an important factor in the Chinese lunisolar calendar and its derivatives. As a circle has 360 degrees and the year has roughly 365 days, the longitude of the sun increments a little less than 1 degree each day.

Accuracy

The accuracy of this calculation depends on the precision of Meeus's calculations, which should be very accurate.

Source

This calculation was sourced from Astronomical Algorithms (1991) by Jean Meeus.