Sidereal vs. Tropical time

Greetings friends,

One of the questions that I am asked fairly often is the difference between Divine Astrology and other Astrology types and why the houses line up differently. Most Astrology is based on Sidereal/Star time, Divine Astrology is based on Tropical/Solar time. Due to this, the locations of the houses are off by one house and one sign from each other. There are proponents of both systems, and the results, in my opinion, are more accurate for Divine Astrology.

Since our daily lives are based on a Solar day, Sidereal (pronounced sigh-deer-ee-ul) seems foreign, but the description is fairly easy. Sidereal Time is literally “Star” time. Our daily lives are based on a Solar day, which is a rotation of the Earth, as well as the movement of the Earth during its revolution of the Sun. Because the Earth has moved about 1.5 million miles further along its orbit of the Sun each day, it takes another 4 minutes for the same spot on the Earth to rotate a little further along its axis and point to the center of the Sun each day. A Sidereal day references other stars much further away than our Sun and therefore does not take into account the revolution of the Earth around the Sun, therefore the additional 4 minutes needed to point back at the Sun is not required in a Sidereal day.

Here is the explanation from Wikipedia at


Sidereal time vs solar time. Above left: a distant star (the small red circle) and the Sun are at culmination, on the local meridian. Centre: only the distant star is at culmination (a mean sidereal day). Right: a few minutes later the Sun is on the local meridian again. A solar day is complete.

I hope that helps.

Sister Sage