Glossary
Shadow period: meaning in astrology
The shadow period is the stretch before and after a retrograde when a planet covers the same degrees it will retrace. The pre-shadow begins when the planet first reaches the degree where it will later station direct; the post-shadow lasts until it passes the degree where it stationed retrograde.
Mercury's shadows add roughly two weeks on each side. Many astrologers treat them as a time to finish and review rather than launch.
Where does "Shadow period" come up on this site?
It is used mainly in the calculators and the methodology page.
How we calculate
Is astrology a guarantee of what will happen?
No. These calculations locate celestial bodies; astrology is a reflection and timing tradition, not evidence of guaranteed health, financial or relationship outcomes.
How are these results calculated?
Positions come from Astronomy Engine, an open-source astronomy library, and are checked against Swiss Ephemeris in our methodology tests. Western readings use the tropical zodiac; Vedic readings subtract the Lahiri ayanamsa. Terms are defined in the glossary.
Next: compare your birth chart, see today's sky, or make a private vision board.