Combust — Astrology glossary

A planet is combust when it sits very close to the Sun, traditionally within about 8 degrees, so its light is overwhelmed and, in older astrology, weakened. In a natal chart a combust planet is read as having its function partly absorbed into the person's core identity, where it works behind the scenes rather than openly. It matters because the planet's qualities can be hard to see from outside, even when they strongly shape the person within. For example, a combust Mercury can give someone whose thinking is so fused with their sense of self that they struggle to view their own ideas objectively. Astrologers distinguish combustion from the much closer, strengthening condition called cazimi, where a planet sits at the Sun's exact heart.