To determine which constellations, intersect the ecliptic, we use the constellation boundaries established by the International Astronomical Union (IAU) in 1930.
It’s important to note that these boundaries were defined for astronomical purposes, not astrological ones.
The table below provides the dates when the Sun passes through each of the twelve astronomical constellations along the ecliptic, accurate to the year 2011. Corresponding tropical and sidereal dates are also included for reference.
|
Constellation
|
Western – Tropical zodiac dates
|
Vedic – Sidereal zodiac dates (Lahiri ayanamsa)
|
Based on IAU boundaries
|
|---|---|---|---|
| Aries | March 21 – April 19 | April 14 – May 14 | April 18 – May 13 |
| Taurus | April 20 – May 20 | May 15 – June 15 | May 13 – June 21 |
| Gemini | May 21 – June 20 | June 16 – July 16 | June 21 – July 20 |
| Cancer | June 21 – July 22 | July 17 – August 16 | July 20 – August 10 |
| Leo | July 23 – August 22 | August 17 – September 16 | August 10 – September 16 |
| Virgo | August 23 – September 22 | September 17 – October 17 | September 16 – October 30 |
| Libra | September 23 – October 22 | October 18 – November 16 | October 30 – November 23 |
| Scorpio | October 23 – November 21 | November 17 – December 15 | Nov 23 – Nov 29 |
| Ophiuchus* | — | — | Nov 29 – Dec 17 |
| Sagittarius | Nov 22– Dec 21 | December 16 – January 14 | December 17 – January 20 |
| Capricorn | December 22 – January 19 | January 15 – February 12 | January 20 – February 16 |
| Aquarius | January 20 – February 18 | February 13 – March 14 | February 16 – March 11 |
| Pisces | February 19– March 20 | March 15 – April 13 | March 11 – April 18 |
Vedic – Sidereal astrology also known as Niryan (Absolute) astrology is directly related with astronomical facts while Western – tropical astrology also known as Sayan astrology is related with the Equinox and the difference between them is Ayanamasa which is 23 degrees currently.