Chandrashtamam is the Moon in the 8th sign from your birth rasi. Kalaprakasika (p. 191) splits it into six kinds by the Moon's star, counted from your birth star in rounds of nine: Suddham: the Pratyari of the second round (star 14), adverse; Sobhanam: the Sadhaka of the second round (star 15), favourable; Kaivartham: the Vadha of the second round (star 16), adverse; Amalam: the Mitra of the second round (star 17), favourable; Siddham: the Parama Mitra of the second round (star 18), favourable; Kshayam: any star of the third round (stars 19–27), adverse. It also sets chandrashtama aside when the Moon is waxing in a benefic sign and navamsa, or when the lords of your rasi and of the 8th from it are friends.
☕ Not one chandrashtamam, but six
The chandrashtamam page explains the basic rule: the Moon in the 8th sign from the sign it was in at your birth, a stretch of about two and a quarter days each month. Kalaprakasika adds a second look at those days: which star the Moon is in, counted from your birth star.
It counts in rounds of nine, as the Pariyaya page explains. If the Moon's star is the 5th, 6th, 7th, 8th or 9th of the second round, the kind is Suddham, Sobhanam, Kaivartham, Amalam or Siddham. If it is in the third round, the kind is Kshayam. The book counts Sobhanam, Amalam, Siddham as favourable and the other three as adverse.
A little arithmetic shows how this fits. When the Moon is in the 8th sign from your birth Moon, its star is always between the 14th and the 19th from your birth star. So each kind falls on one star count, and Kshayam can only be the 19th. This is our working, not a line in the book.
The rule this page explains is the grading by kind. Nava Panchangam does not use this rule in its day score. This page explains it as the books give it. The day score still counts chandrashtamam itself, and it treats every one the same way, whatever its kind. That is the app's simplification.
The six kinds, and the two cancellations
- Suddham: the Pratyari of the second round (star 14), adverse
- Sobhanam: the Sadhaka of the second round (star 15), favourable
- Kaivartham: the Vadha of the second round (star 16), adverse
- Amalam: the Mitra of the second round (star 17), favourable
- Siddham: the Parama Mitra of the second round (star 18), favourable
- Kshayam: any star of the third round (stars 19–27), adverse
- The Moon is waxing, in a benefic sign and in a benefic navamsa
- The lords of the birth rasi and of the 8th sign from it are friends
Frequently Asked Questions
How do I find which kind a chandrashtamam is?
Count from your birth star to the star the Moon is in during the chandrashtamam, both included. 14 is Suddham, 15 Sobhanam, 16 Kaivartham, 17 Amalam, 18 Siddham, and 19 Kshayam.
Does the book say three kinds are good?
Yes: Sobhanam, Amalam, Siddham. It calls Amalam a yoga that sets the adverse effects aside, and Siddham one of success.
Which friendship table does the second cancellation use?
The book does not say. For an Aries or Libra rasi the 8th sign has the same lord (Mars, Venus), and the book does not say how to read that case.
Does the app grade chandrashtamam into kinds?
No. Its day score treats every chandrashtamam the same way. This page explains Kalaprakasika's grading as the book gives it.
From the source
Which kinds can actually occur, two small inconsistencies in the print, and what this page leaves out.
🔢 Which kinds can occur
We checked every pair of birth quarter and Moon quarter. With the Moon in the 8th sign from the birth Moon, its star is the 14th to the 19th from the birth star, never earlier or later. So the third round, which the book names in full, is reached only at its first star.
| Kind | Moon's star from the birth star | Grade | Can it occur? |
|---|---|---|---|
| Suddham | 14 | adverse | yes |
| Sobhanam | 15 | favourable | yes |
| Kaivartham | 16 | adverse | yes |
| Amalam | 17 | favourable | yes |
| Siddham | 18 | favourable | yes |
| Kshayam | 19–27 | adverse | only at 19 |
📝 Two small inconsistencies in the print
On p. 191 the book first lists the kinds as Suddham, Sobhanam, Siddham, Kaivartham, Amalam, Kshayam, and then assigns Kaivartham to the 7th and Siddham to the 9th. This page follows the assignments. The 7th is also spelled two ways, Kaivartham and Kavarthim; this page uses the first. The rounds are defined on p. 166.
✂️ What this page leaves out
The book gives the adverse kinds a short outcome and the favourable ones a promise. This page keeps only its grade, favourable or adverse.