This is crazy! I'm a Scorpio and will always be a Scorpio LOL. Especially because I have a Scorpio tattoo... I don't want to change it :)
Nasa is dusting off one of their earlier investigations about the astrological chart. Check it out. The ancient Babylonians actually had 13 signs, but left one off because the idea conflicted with a 12-month calendar. The 13th sign is apparently called Ophiuchus. I have no idea how to pronounce it LOL. It falls between Scorpio and Sagittarius. If you are an Ophiuchus, you are very curious, hot-tempered and stubborn. The representation for the sign is a man holding a snake. Check it out... this 13th sign would shift other signs too!! This is what the new Zodiac line up would look like! (YourTango.com has all the details if you want to check it out!!)
Capricorn: January 20 – February 16
Aquarius: February 17 – March 11
Pisces: March 12 – April 18
Aries: April 19 – May 13
Taurus: May 14 – June 21
Gemini: June 22 – July 20
Cancer: July 21 – August 10
Leo: August 11– September 16
Virgo: September 17 – October 31
Libra: November 1 – November 23
Scorpio: November 24 – November 29
Ophiuchus: November 30 – December 18
Sagittarius: December 19 – January 19