The Chaturvimsamsa, also called the Siddhamsa, is the twenty-fourth divisional chart: each sign is cut into twenty-four parts of 1 degree 15 minutes, counted forward from Leo in an odd sign and from Cancer in an even sign. Brihat Parashara Hora Shastra ch. 6 assigns the D24 to education and learning, and it is read beside the 4th and 5th houses of the birth chart.
Twenty-four parts of 1 degree 15 minutes fill a sign, and where the count begins depends on parity: Leo for an odd sign, Cancer for an even one. Those two are the signs of the Sun and the Moon, which is the same pairing the Hora division uses, and from the chosen start the twenty-four parts run forward through the zodiac, wrapping twice.
Because twenty-four is twice twelve, the parts cover the whole zodiac exactly twice within one sign. A planet's D24 sign therefore advances by one for every 1 degree 15 minutes it moves, and returns to the starting sign at the halfway point of the original sign.
The classical subject is education and learning, so the D24 is read against the 4th house, which carries formal schooling, and the 5th, which carries intelligence and the capacity to learn, with Mercury and Jupiter as the natural significators of the two. The division adds resolution to what those houses already indicate.
That pairing is the whole of what the classical sources settle here. AstroZivi names the subject and computes the chart; it does not turn a placement into a statement about degrees, examinations or a field of study, because no reading it can cite supports that step.
A chaturvimsamsa is 1 degree 15 minutes wide, which the ascendant crosses in about five minutes on average. A birth time rounded to the nearest quarter hour will therefore land the D24 lagna in one of about three possible signs, and a time rounded to the hour is useless for the ascendant of this chart.
The planets are a different matter. Even the Moon, at roughly thirteen degrees a day, takes over two hours to cross a D24 part, so the planetary side of the chart remains stable under a birth-time error that destroys the lagna. If your time is uncertain, read the planetary placements and treat the D24 houses as provisional until the chart is rectified.
Brihat Parashara Hora Shastra ch. 6 assigns the Chaturvimsamsa, also called the Siddhamsa, to education and learning. It is read beside the 4th house for formal schooling and the 5th for intelligence, with Mercury and Jupiter as the significators.
Divide each sign into twenty-four parts of 1 degree 15 minutes. The count starts from Leo in an odd sign and from Cancer in an even sign, and runs forward through the zodiac, covering it twice within a single sign.
Yes. Siddhamsa and Chaturvimsamsa are two names for the same twenty-fourth division, and both are used for the same chart of 1 degree 15 minute parts.
To within a few minutes. The ascendant crosses a 1 degree 15 minute part in about five minutes on average, so a time rounded to the quarter hour leaves the D24 lagna uncertain across about three signs. The planetary placements are much more stable.
No. The classical sources give the chart its subject, education, and not a list of fields, and AstroZivi publishes a reading only where a named text and verse support it. The page reports the D24 signs, houses, degrees and dignities.
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