But the image on the coin, of a ram looking over its shoulder at a star, sent the Rutgers University astronomer to dusty astrological texts to interpret its meaning. And what he found was the key, he believes, for unlocking the secret of the Star of Bethlehem.

The Star of Bethlehem has mystified and intrigued Bible scholars and astronomers (and those who fancied themselves a bit of both) for centuries.

The second chapter of Matthew's Gospel describes a unique celestial phenomenon that somehow escaped the notice of King Herod and the rest of Judea yet attracted mysterious visitors from the distant east, seeking a newborn king.

A number of celestial events have been proposed to explain the Bethlehem Star. A newly revised Bible Handbook, issued this year by the Zondervan Publishing House, states "there's one and only one astronomical object" that meets all of the Biblical criteria: a comet.

Molnar, who earned his Ph.D. from the University of Wisconsin in 1971, is sure it's not a comet. In an interview, Molnar said ancient astrology texts never refer to the birth of anybody related to a comet. Comets usually signal disaster, such as a war or the death of a king, he said.

In those ancient texts Molnar discovered that Aries the Ram was the zodiac symbol for the ancient kingdom of Judea, something that most scholars had apparently missed. Its appearance on his coin, minted in Antioch around A.D. 6, probably symbolized the solidification of Roman rule of the region.

Based on that information, he then went looking for the kind of celestial event that would have signaled to ancient astrologers like the Magi that something as memorable as the birth of a king was about to take place. "I really had to think like them," he said. "What would they look for?"

His research lead him to the morning of April 17, 6 B.C. The planet Jupiter, named after the supreme deity of the ancient Romans, came over the horizon that morning accompanied by a host of other celestial signs that would have been like flashing neon light to the astrologers.

April 17, 6 B.C., Bethlehem, Israel
time: Jupiter rising
(click on image to enlarge)

The moon and the sun were both right there, and Saturn was nearby, all within the sign of Aries the Ram. "All of these things, according to ancient manuscripts, indicated the birth of an incredibly powerful king," Molnar said.

Restudying the original Greek of Matthew's Gospel account Molnar saw a very technical description of exactly what occurred that April, as well as later in the year.

"These are also astronomical terms," he said. "'In the east,'" in Greek, meant 'at morning rising in the east.' Words for 'going forward' and 'stood over' were the same as what we call today retrograde motion."

Retrograde motion is an optical illusion created by the orbits of the planets. As the earth's orbit catches up to another planet, such as Jupiter, the planet's movement across the sky appears to slow and stop.

Later that summer and fall, Jupiter underwent retrograde motion. "I believe this was the time the wise men were visiting King Herod and had their audience with him," Molnar said.

Molnar's colleagues at other East Coast universities seem to consider his new book, The Star of Bethlehem, a major breakthrough. Bradley Schaefer of Yale writes, in a Sky & Telescope review, that all the old Star of Bethlehem theories are now irrelevant.

Harvard's Owen Gingrich, in an endorsement on the book jacket, calls it "the most original and important contribution of the entire twentieth century on the thorny question of how events recorded there should be interpreted."

Molnar says the book, which was issued in October 1999 by Rutgers University Press, is now in its second printing.