What combustion and cazimi mean
All of this is measured as a pure ecliptic separation — how many degrees a planet sits from the Sun along the zodiac. Traditionally, a planet within about 8°30′ of the Sun is combust: too close to the Sun's light to be visible, its meaning 'burned up' or absorbed into the solar will. A planet that instead sits within roughly 17 arcminutes — effectively on the same degree — is cazimi (from the Arabic for 'in the heart'): not weakened but exalted, fused with the Sun's power.
Between the combustion orb and about 17° the tradition calls a planet 'under the beams' — just outside the worst of the glare but still hard to see. Beyond 17° the planet is free, rising or setting far enough from the Sun that observers see it and, in the traditional reading, it operates visibly in life.
How we compute it
We take the natal Sun's ecliptic longitude and the longitude of every other body from sub-arcsecond astronomy (VSOP87/ELP via astronomy-engine), and compute each planet's shortest angular distance from the Sun. That single number decides the state on our published orbs: cazimi at 17′ (0.283°) or less, combust to 8°30′, under the beams to 17°, free beyond.
The table sorts from the closest body to the Sun outward, so the most solar-modified planets appear first. We show the Sun itself separately as the reference point, and we report each planet's daily motion so you can see whether it is also retrograde.
What you get
After entering one birth date, time and place, the report shows:
- Your natal Sun's sign and degree — the reference for every measurement.
- A sorted table of the nine other bodies with their exact distance from the Sun.
- Each body's classical condition: cazimi, combust, under the beams, or free — colour-coded.
- A short note on what each condition means, plus a reminder that orbs vary by authority.
How the conditions are traditionally read
Traditional readers describe combustion as a planet whose voice the Sun drowns out — the function it represents operates but blends into the core identity (the Sun), which often overrules it. Classically this is the hardest placement for a planet to 'show' in a chart.
Cazimi reverses the pattern: tradition treats the planet as at its most potent, welded to the solar will. Under the beams names a milder version of combustion, and 'free' planets are the ones a traditional astrologer reaches for first when describing visible, workable talents.
This is one of the oldest and most consistently-documented rules in Hellenistic and medieval astrology — its logic is purely astronomical (how close two objects appear in the sky), which is exactly why we can compute it exactly. Tradition, not measurement, assigns the interpretive weight.
A worked example: born 1 January 2000, 17:30 UTC, London
Here the Sun stands at 10.6° Capricorn. The planet nearest it is Mercury at 2.2° Capricorn — only 8.36° away — which lands inside the 8°30′ orb, so Mercury is reported as combust: a thinking-and-voicing function fused close to the Sun's own agenda. Every other body sits far from the Sun, so the whole table below Mercury reads as free.
A second chart shows the opposite extreme: for a 21 June 2000 noon London birth the Sun is at 0.7° Cancer and both Venus (2.76° away) and Mars (2.93° away) fall deep inside the combustion orb together — a textbook solstice stellium of scorched planets. No planet in either example is cazimi, which is uncommon: to be within 17′ of the Sun is a genuinely rare, exact conjunction.
What this tool does not claim
Orb sizes for combustion are not universal — authorities give anything from 8° to 17° as the combustion limit, and some draw the Cazimi star as precisely 17′ while others round to 1°. We use the common Ptolemaic set (17′ / 8°30′ / 17°) and state it so a borderline planet is never a mystery.
We measure separation along the ecliptic (longitude only); the classical 'oriental/occidental' distinction additionally involves rising order and is not part of this simplified, transparent tool. Combustion's interpretive tradition has no controlled support, like natal astrology generally. The geometry is exact; we offer the meaning for reflection. All computation runs locally; your birth data never leaves your browser.
Where it sits next to other readings
Essential dignity by sign — domicile, exaltation, detriment and fall — is covered by our Traditional Chart tool, and the whole classical house-by-house picture by the same page. This tool isolates the one dignity axis the Traditional Chart leaves out: each planet's condition relative to the Sun.
Our method in one line
Ecliptic longitude of every body from sub-arcsecond astronomy (VSOP87/ELP via astronomy-engine), measured against the natal Sun and binned into cazimi / combust / under-the-beams / free on stated Ptolemaic orbs. Reviewed by Dr. Amara Osei, Astronomy Reviewer.
Step by step
- 1
Enter one birth record
Date, time and place — the Sun's exact degree at that instant anchors every separation.
- 2
Scan the closest first
The table is sorted by distance from the Sun, so any combust or cazimi planets are right at the top.
- 3
Read the badge
Each body carries its condition and a one-line meaning — the Sun-relative strength or concealment the tradition assigns it.
- 4
Cross-check the orbs
A borderline planet near 8°30′ or 17° is exactly where authors disagree; the tip is to note the distance, not just the label. Tip: cazimi needs a near-exact conjunction — most charts simply have none.
Frequently asked questions
- What does it mean when a planet is combust?
- A combust planet sits so close to the Sun that, from Earth, it is lost in the Sun's glare and cannot be seen. Traditional astrology reads that as the planet's function being absorbed into, or overridden by, the core identity — it operates, but quietly and fused with the solar will rather than as a separate voice.
- Is cazimi good or bad?
- Counter-intuitively, the tradition treats cazimi as strong, not weak. Being exactly on the Sun's degree (within about 17 arcminutes) is 'in the heart of the Sun' — the planet is pictured as exalted and invested with solar power, rather than burned up the way a merely combust planet is. It is a very specific, narrow orb, which is why it is uncommon.
- How close does a planet have to be to be combust?
- It depends on the authority. We use 8°30′ as the combustion orb and 17° as the limit of 'under the beams', following the common Ptolemaic scheme. Others widen combustion to 17° or narrow the cazimi star. Because the boundary is conventional, we always print the exact separation so you can judge a borderline case yourself.
- Does being retrograde change a planet's condition?
- Retrograde motion and combustion are separate conditions and can combine — a planet can be both retrograde and combust. We show both so you can see each planet's full solar relationship, but this tool's states are defined purely by angular distance from the Sun.
- Is my birth data private?
- Calculations run entirely in your browser. Your birth data is never uploaded, never stored on a server, and never shared. The separations are computed locally from your natal positions; nothing is uploaded or stored.
Written by
Elena Marchetti
Founder & Staff Astrologer
Methodology reviewed by
Dr. Amara Osei
Astronomy Reviewer
Published 2026-10-01 · Updated 2026-10-01 · Calculated with sub-arcsecond astronomy (VSOP87/ELP via astronomy-engine)