What is chandrashtamam?
Chandra means Moon. Ashtama means eighth. Chandrashtamam is the days when the Moon passes through the 8th zodiac sign from your own birth sign, and it is considered an inauspicious period.
Unlike Rahu Kalam and Gowri Nalla Neram, which are the same for everyone, chandrashtamam is personal. It depends on which zodiac sign (rashi) the Moon was in when you were born. Two people born under different nakshatras can have chandrashtamam on entirely different days.
How it is calculated
The calculation requires two things: your birth sign and the Moon's current position. Your birth sign is derived from your birth nakshatra, there are 27 nakshatras spread across 12 zodiac signs (rashis), so each sign contains 2 or 3 nakshatras.
- Find your birth nakshatra (the nakshatra the Moon was in when you were born).
- Look up the corresponding birth sign (janma rashi) in the table below.
- Count 8 signs forward from your birth sign, that is your chandrashtamam sign.
- When the Moon passes through that sign, you are in chandrashtamam.
The 12 zodiac signs and their nakshatras
| Rashi | Tamil | Nakshatras |
|---|---|---|
| Mesha (Aries) | மேஷம் | Ashwini, Bharani, Krittikai (1st quarter) |
| Rishabha (Taurus) | ரிஷபம் | Krittikai (2nd–4th), Rohini, Mrigashirsham (1st–2nd) |
| Mithuna (Gemini) | மிதுனம் | Mrigashirsham (3rd–4th), Thiruvadhirai, Punarpoosam (1st–3rd) |
| Kataka (Cancer) | கடகம் | Punarpoosam (4th), Poosam, Ayilyam |
| Simma (Leo) | சிம்மம் | Magam, Pooram, Uthiram (1st–2nd) |
| Kanni (Virgo) | கன்னி | Uthiram (3rd–4th), Astham, Chithirai (1st–2nd) |
| Thula (Libra) | துலாம் | Chithirai (3rd–4th), Swathi, Visakam (1st–3rd) |
| Vrischika (Scorpio) | விருச்சிகம் | Visakam (4th), Anusham, Kettai |
| Dhanus (Sagittarius) | தனுசு | Moolam, Pooradam, Uthiradam (1st–2nd) |
| Makara (Capricorn) | மகரம் | Uthiradam (3rd–4th), Thiruvonam, Avittam (1st–2nd) |
| Kumbha (Aquarius) | கும்பம் | Avittam (3rd–4th), Sadhayam, Poorattadhi (1st–3rd) |
| Meena (Pisces) | மீனம் | Poorattadhi (4th), Uthirattadhi, Revathi |
The chandrashtamam table, your 8th sign
The table shows which sign triggers chandrashtamam for each birth sign. You only need your own row.
| Your birth sign | Your chandrashtamam sign |
|---|---|
| Mesha (Aries) | Vrischika (Scorpio) |
| Rishabha (Taurus) | Dhanus (Sagittarius) |
| Mithuna (Gemini) | Makara (Capricorn) |
| Kataka (Cancer) | Kumbha (Aquarius) |
| Simma (Leo) | Meena (Pisces) |
| Kanni (Virgo) | Mesha (Aries) |
| Thula (Libra) | Rishabha (Taurus) |
| Vrischika (Scorpio) | Mithuna (Gemini) |
| Dhanus (Sagittarius) | Kataka (Cancer) |
| Makara (Capricorn) | Simma (Leo) |
| Kumbha (Aquarius) | Kanni (Virgo) |
| Meena (Pisces) | Thula (Libra) |
How long does it last?
The Moon spends about 2–2.5 days in each zodiac sign. Chandrashtamam therefore typically lasts 2–2.5 days and returns approximately every 27 days, matching the Moon's orbit through all 12 signs.
The exact start and end times depend on the Moon's speed, which varies slightly. Our calculator uses astronomical positions and provides times accurate to the nearest minute.
What should you avoid during chandrashtamam?
Chandrashtamam is considered a period of reduced mental clarity and heightened sensitivity. The tradition recommends avoiding:
- New beginnings, signing contracts, starting a business, moving house.
- Major decisions, changing jobs, large purchases, financial commitments.
- Travel, especially long journeys and flights.
- Confrontations, important conversations and negotiations.
Daily routines are not affected. Chandrashtamam, like Rahu Kalam, applies only to new beginnings and important steps. You do not need to stop working, eating, or sleeping.
The difference from Rahu Kalam and Gowri
| Element | Applies to | Duration | Personal? |
|---|---|---|---|
| Rahu Kalam | Everyone | ~1.5 hours daily | No, same for everyone in the same city |
| Gowri Nalla Neram | Everyone | 4 segments of daylight | No, same for everyone in the same city |
| Chandrashtamam | Individual | ~2–2.5 days | Yes, depends on your birth nakshatra |
Chandrashtamam is part of the broader gochara system, the Moon's transit through the 12 houses as seen from your birth sign. In this system, houses 1, 3, 6, 7, 10, and 11 are considered favourable, houses 2, 5, and 9 neutral, and houses 4, 8, and 12 unfavourable. Chandrashtamam is specifically house 8.