When a planet comes very close to the Sun in the zodiac, it is lost in the Sun's glare and cannot be seen. Vedic astrology calls this asta, combustion. A combust planet is said to lose some of its power to give independent results, its significations "burnt" by the Sun.
Classical combustion distances
Commonly used distances (in degrees from the Sun) are:
| Planet | Combust within |
|---|---|
| Moon | 12° |
| Mars | 17° |
| Mercury | 14° (12° when retrograde) |
| Jupiter | 11° |
| Venus | 10° (8° when retrograde) |
| Saturn | 15° |
Rahu and Ketu are never combust. Some astrologers apply combustion only within the same sign; most use the distance alone.
How a combust planet behaves
- Its karakatvas (natural significations) are weakened: a combust Venus can reduce comfort or harmony in relationships; a combust Jupiter, the support of teachers or children.
- The houses it rules may need more effort to deliver.
- The planet's qualities often merge with the Sun's: ego, authority and the father become entwined with that planet's themes.
When it matters less
- Mercury is so often close to the Sun (never more than about 28° away) that many astrologers treat its combustion lightly, especially in the same sign (Budha-Aditya yoga is even considered favourable).
- A combust planet that is exalted, in its own sign or strong in the Navamsa retains much of its strength.
- Deep combustion (within a few degrees) is more significant than a planet at the edge of its range.
Combustion in muhurta
For weddings, a combust Jupiter or Venus (Guru asta, Shukra asta) is traditionally avoided altogether; marriages are not fixed during these periods. Wedding muhurtas are chosen as part of our matchmaking service.
Common questions
Is a combust planet always bad?
No. A combust planet in its own or exaltation sign, or strong in the Navamsa, keeps much of its strength. Light combustion at the edge of the range matters far less than deep combustion within a few degrees.
Does combustion affect the dasha of that planet?
It can make the planet's period less independent: results arrive through authority figures, the father or the government (the Sun's themes), or need more effort. The houses the planet rules still give their results.
Why is Mercury's combustion treated lightly?
Mercury is never more than about 28° from the Sun, so it is combust in a large share of charts. Many astrologers ignore it unless it is very deep, and Sun–Mercury together even form the favourable Budha-Aditya yoga.
Combustion is one of the strength factors read alongside dignity and retrogression. Your free birth chart marks combust planets.