Lahiri Ephemeris
लाहिरी एफेमेरीस
Lahiri Ephemeris, founded by N.C. Lahiri in 1944, is the foundational sidereal ephemeris that defined the Lahiri (Chitra-paksha) Ayanamsa — adopted by the Government of India in 1955 as the standard for the Rashtriya Panchang. Every major Indian astrologer and panchangam-maker uses Lahiri's tables for sidereal position calculation.
Key Facts
| Region | India (National) |
| Language | English (Sanskrit terms) |
| Publisher | Astro Research Bureau, Kolkata |
| Founder | Nirmal Chandra Lahiri (1906-1980) |
| Founded | 1939 (ephemeris); 1955 (Lahiri Ayanamsa adopted as Govt of India standard) |
| Calculation | Drik Ganita with Lahiri (Chitra-paksha) Ayanamsa — the de facto government standard |
| Website | www.lahirisephemeris.com |
| Where to Get | Astro Research Bureau Kolkata; major astrological bookstores; online astrology suppliers |
N.C. Lahiri — The Man Behind India's Sidereal Standard
Nirmal Chandra Lahiri (1906-1980) was a Bengali astronomer-astrologer who systematized sidereal astronomical calculations for the Indian Vedic tradition. After studying both classical Siddhantic astronomy and modern Western positional astronomy, he founded the Astro Research Bureau in Kolkata in 1944 and began publishing his annual ephemeris.
The Lahiri Ayanamsa
Lahiri's most lasting contribution was fixing the value of the Ayanamsa — the angular difference between the tropical (Sayana) and sidereal (Nirayana) zodiacs caused by axial precession. He anchored his system to the fixed star Chitra (Spica) being at 180° (Tula 0°) at a specific reference date, giving the Chitra-paksha Ayanamsa — known worldwide as the Lahiri Ayanamsa.
The Calendar Reform Committee (Saha Committee, 1955) adopted Lahiri Ayanamsa as the official standard for the Rashtriya Panchang, making it the de facto Indian national standard. As of 2026, the Lahiri Ayanamsa value is approximately 24° 13′.
What the Ephemeris Contains
- Daily geocentric longitudes of Sun, Moon, Mars, Mercury, Jupiter, Venus, Saturn, Rahu, Ketu
- Both sidereal (Nirayana, Lahiri Ayanamsa) and tropical (Sayana) positions
- Daily ayanamsa value
- Sunrise/sunset for major Indian cities
- Tithi, nakshatra, yoga, karana
- Eclipse data
- Planetary aspects, retrogressions, combustions
Who Uses It
Lahiri Ephemeris is the working reference for: the Government of India's Rashtriya Panchang, almost all regional Drik Panchangams (Telugu, Tamil, Kannada, Kerala, Marathi), professional astrologers across India, and digital platforms including Drik Panchang and Nitya Panchangam itself.