Before the 16th century, Christians generally assumed that the Star of Bethlehem must have been some kind of astrological miracle. For instance, the Church Father St John Chrysostom, believed that the Star of Bethlehem literally came down from heaven and stood over the manger where Jesus lay. However, the great astronomer Johannes Kepler (1571-1630) challenged this assumption.
Kepler’s interest in the Star of Bethlehem was first prompted by his fascination with the rare conjunctions of Saturn and Jupiter. Every 20 years for a duration of 200 years there is a series of conjunctions of Saturn and Jupiter under fiery zodiac signs, followed by a series of conjunctions under the earthy zodiac signs, then 200 more years of conjunctions under the airy zodiac signs, and finally 200 years of conjunctions under the watery zodiac signs, thus making up an 800-year cycle of conjunctions.
