For centuries astronomers have speculated about the famous Star of Bethlehem, which the three Magi (the three wise men/the three kings) followed to the place of Christ’s birth. Of course, the star may defy scientific explanation altogether, and be viewed as a miracle. Nevertheless, various astronomical theories have been proposed, including that the star may have been a comet, or a supernova (an exploding star), or a “planetary conjunction” (a gathering of planets in one part of the sky). In this column, we’ll examine two of today’s most popular theories, both of which hold that the planet Jupiter played a key role.