Castor is one of the two dominant stars in the constellation Gemini the twins. It is actually a binary with one half at magnitude 1.58 magnitude and the other at 3.7, and upon closer inspection it's really a sextuple system. Castor is one of the closer stars to us and is a very bright white with a slight bluish tint. As of 2011-12 it is located at RA 7h35m20s and at decl.31°52'.

Astrologically and mythologically, Castor is the mortal half of Gemini the Twins(Pollux is the immortal half), famous for his skill with horses. While Pollux was born of Zeus(god) and Leda(human queen of Sparta), Castor was born of Leda and her husband king Tyndareus. Despite his mortality, Castor worked well with Pollux and both were deified for their efforts by Zeus. One of their feats was sailing with Jason the argonaut in search of the Golden Fleece.

Castor's nature is said to be Mercurial with a tinge of Mars making it intellectual, mischievous, and often violent. There is sudden fame and honor followed by loss and disgrace. It also brings mental or nervous disorders and injury to the limbs. It is a generally unfortunate influence unless combined with other more positive influences such as the Sun or Jupiter.

Castor was in tropical Gemini untill around 534 AD when it then moved into tropical Cancer. This is just around the time when the Middle Ages began and after the fall of the ancient Roman Empire(476 AD). Castor has acquired more prudence and sensitivity in Cancer but still retains its childish or mischievous ways. What influence will it have on Jerusalem when it crosses its zenith around 2050 AD? Will Jerusalem become the HOMELAND for many diverse faiths and a worldwide center of education, or will it be the spark or powder keg for war and divisiveness? Are the biblical prophecies of the New Jerusalem or the Messiah's coming in any way associated with the descent of this great star over this great city?