(Information added by Jenwytch from Wikipedia.)

Sun Signs and Dates ~ a reference guide

The following table shows both traditional and modern rulerships.

Symbol Unicode
Char
Sign names Dates Ruling
celestial body
Modern
Ruling
celestial body
Classical
Ram Aries March 21 – April 19 Mars Mars
Bull Taurus April 20 – May 20 Earth (Modern),
Ceres
Venus, & Earth
as special ruler
Twins Gemini May 21 – June 20 Mercury Mercury
Crab Cancer June 21 – July 22 Moon Moon
Lion Leo July 23 – August 22 Sun Sun
Virgin Virgo August 23 – September 22 Ceres (Modern),
Chiron
Mercury, & Ceres
as special ruler
Balance Libra September 23 – October 22 Venus Venus
Scorpion Scorpio October 23 – November 22 Pluto Mars
Archer Sagittarius November 23 – December 21 Jupiter Jupiter
Goat Capricorn December 22 – January 19 Saturn Saturn
Water Bearer Aquarius January 20 – February 18 Uranus Saturn
Fish Pisces February 19 – March 20 Neptune Jupiter

 

The dates given above vary slightly from year to year.

For a more detailed (yet relatively brief) description of Astrology and the Zodiac signs please read this Wikipedia article.