What Exactly Was the Star of Bethlehem?

Only one astronomical body matches Matthew’s description of the Star perfectly — a comet.

Along with the angel, the Star of Bethlehem vies for top spot on our Christmas trees. We send Christmas cards with the Star embossed on them. In the Church of the Nativity the spot where Jesus was supposedly born is marked by a silver star. The Bethlehem Star has come to symbolize Christmas and encapsulate the whole Nativity Story.

cometFor Matthew, who recounts the story of the Magi, the appearance of the Star at the time of Jesus’ birth and its leading of the Magi right to him is an impressive confirmation that Jesus is the Messiah. If what Matthew describes did indeed occur, it would certainly be that, and it would underline Matthew’s reliability as a historically accurate biographer. In addition, it would be a marvelous demonstration of God’s control of the cosmos.

That the Star was an astronomical body is strongly suggested by, among other things, Matthew’s word “star” (astēr) and the astronomical term “rising” (Matthew 2:2, 9).

But what precisely was the Star? A quick look at Matthew’s account reveals that, whatever the Star was, it was first observed by the Magi more than a year before Herod’s slaughter of Bethlehem’s infants. And many months after this first appearance, it did something in connection with a “rising” in the eastern sky that deeply impacted the Magi. Then, within a couple of months of that, the Star was in the southern evening sky ushering the eastern astrologers to Bethlehem before standing over the house, pinpointing it as the place where the Messiah was. This information eliminates all of the hypotheses offered to explain the Star except one.

The case for the great Christ comet

Only one astronomical body matches Matthew’s description of the Star perfectly — a comet. Origen, in the third century, identified the Star as a comet and made a detailed case for this. No other astronomical view is as at home in the earliest centuries AD as the comet view. At the turn of the second century, Ignatius’ description of the Star (“a brightness beyond all the stars”; “its newness caused astonishment”; “unlike anything else [in the heavens]”) is very consistent with a bright comet. What the Protevangelium of James (mid-second century) records concerning the Star (“an immense star shining among these stars and causing them to become dim”) is also compatible with a large and bright comet.

The case for the Star being a comet, one of the dark, icy dirtballs that develop a head (coma) and a tail (or two) as they come close to the Sun, is formidable. The movement of the Star within a couple of months from the eastern morning sky, where it was when it “rose,” to the southern evening sky, where it was at the climax of the Magi’s journey, demands that it was a comet.

The Star’s sudden appearance and strangely long period of visibility is strikingly consistent with a large long-period comet, like Hale-Bopp, which remained visible to the naked eye for a total of 18 months in 1996–97.

The fact that the Star did something surprising and extraordinary in connection with its “rising” strongly favors a comet making a close pass by the Sun. The “risings” of other celestial bodies were predictable and visually unimpressive, but those of comets were unpredictable and could be astonishing. This is because comets are at their most active, even hyperactive, when they’re closest to the Sun.

As for the Star’s “going before” the Magi and “standing over” a particular location, comets are described in precisely these terms by ancient writers. The Greek historian Diodorus Siculus relates how a comet “went before and led” Timoleon as he sailed westwards to Sicily. The Roman historian Josephus tells of how a sword-like comet “stood over” Jerusalem in the period prior to its destruction. A comet setting with its tail streaming upwards is uniquely well equipped to play the role of the Star as it pinpointed the location of the baby.

Comets historically meant good news

On quite a few occasions comets were regarded as heralds of good news. A book on comets by the Stoic scholar Chaeremon (early first century AD) gave examples of positive cometary omens. Comets in 135/134 BC and 120/119 BC were regarded as announcing the greatness of Mithridates VI Eupator on the occasion of his birth and coronation respectively. A great comet in 44 BC was generally embraced as an excellent omen, signalling Julius Caesar’s reception among the gods, and was privately interpreted by Octavian (Caesar Augustus) as an auspicious omen for his own reign. One comet during Nero’s reign was said by Seneca to have redeemed comets of their bad reputation.

Remarkably, the Mesopotamian seer Balaam’s oracle concerning the Messiah’s appearance in Numbers 24:17 speaks of him in terms that are distinctly cometary — he will be a “scepter” (Revised English Bible: “comet”) and a “star” that “shall rise” — alluding to the celestial phenomenon that would announce his birth. Many Matthew scholars have rightly detected an allusion to Balaam’s oracle in Matthew 2:2’s “we saw his star at its rising.” Early Christians such as Justin Martyr, Irenaeus, and Origen also regarded the Star as a fulfillment of Numbers 24:17.

According to Matthew, the Magi discerned a lot of information from the Star — that someone had been born, that he was a king — indeed the king of the Jews — and that he was worthy of worship. Through their movements within and among the constellations, comets were exceptionally capable of conveying significant and complex messages to suitably educated observers.

We know from surviving comet records from Babylon that two of the five key moments of a comet’s career that were of special interest to Babylonian astronomers were the comet’s first appearance and its “rising.” Curiously, it is to these two occasions in the Star’s career that Matthew makes explicit reference.

Another factor favoring the identification of the Star as a comet is the evident uniqueness of the Star — after all, the Magi weren’t in the habit of traveling in search of newborn kings! No two comets are identical or put on the same show for human observers. This is not only because comets are very individual (in size, chemical constituency, orbit, etc.), but also because they appear at different times of the year, when Earth is at different stages of its orbit.

The Christ Comet was superior

So which comet was it? Could it have been Halley’s Comet, which appeared in 12 BC? No, that would have the Magi arriving six years too early. Plus it was only visible for 56 days, never had a “rising,” and did not appear in the southern sky. What about the comet recorded by the Chinese in 5 BC? Again, no, because it was only observable for 70 days and did not “rise.” The Christ Comet was superior to them.

The records of fewer than one-third of all comets from 50 BC to AD 50 have survived. Of the ones that we do know about, in half of the cases there would have been no record of the comets except for scattered references in Greco-Roman literature. So it is hardly surprising that, with respect to the Star comet, we are dependent on scattered references in early Christian literature.

The case for the Star of Bethlehem being a great comet in the mould of Hale-Bopp is impressive.

Image courtesy of Shutterstock.

Colin R. Nicholl
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