Tonight, look towards the east-southeast about one hour after sunset, and you might catch a glimpse of the constellation Ophiuchus (the Serpent Bearer). His head is marked by the star Rasalhague. Ophiuchus is joined in legend and in the sky to the constellation Serpens (the Serpent). The constellation is identified with Aesculapius, who is said to have been the first doctor, after learning the secret of healing from a snake. (The symbol of a staff with a serpent around is seen in hospitals today.)
Ophiuchus is the 13th zodiac constellation, between Scorpius and Sagittarius. For about two weeks, between 1st and 15th of December, the sun lies within its boundaries.
A small note: As most people already know, the signs don’t match the actual positions of the constellations. The reason is due to precession; the earth has a slow wobble - taking 26,000 years to do one cycle. This causes the Zodiac constellations to drift through the sky. The ancient astrologers 4,000 years ago chose signs that matched the star patterns. But today, because of precession, the moving constellations have left the signs far behind. So today they are seriously out of step by about 1 sign.
