Jimmy Westlake's Celestial News column appears Tuesdays in the Steamboat Today.
Find more columns by Westlake here.
Steamboat Springs About 2,000 years ago, St. Matthew recorded that something extraordinary appeared in the sky over Bethlehem of Judea that accompanied the birth of Jesus. For centuries, astronomers have wondered about the nature of this Star of Bethlehem. Was it a one-time supernatural event, never seen before and never seen since? Although that is a possibility, it seems unlikely that St. Matthew would have been the only person to record the appearance of an amazing event like that. Another possibility is that the Star of Bethlehem was a rare but natural celestial event that might have gone unnoticed by the masses but would have caught the attention of sky watchers, such as the Magi mentioned in St. Matthew's gospel.
Assuming this to be the case, what type of object could it have been? A bright comet would have been noticed and recorded by sky watchers worldwide, so that seems unlikely. The spectacular death of a nearby star in a supernova explosion would have made a brilliant and temporary star in the heavens, but supernovas leave tell-tale signs such as expanding clouds of gas that modern astronomers would have found, had there been one. The best explanation for the Star of Bethlehem is that an unusual grouping of the bright planets in the sky might have been interpreted by sky watchers of the day as a sign heralding the birth of a King.
Running the solar system clock backward, astronomers have identified two very unusual groupings of the planets that might have been the Star of Bethlehem, one occurring in 7 B.C. and the other in 2 B.C. Both of these planetary groupings involved the planet Jupiter, considered to be the king of the planets. Throughout several months in 7 B.C., the planets Jupiter and Saturn had a rare triple conjunction while in the constellation of Pisces, the Fish. On the morning of June 17 in the year 2 BC, the two brightest planets, Jupiter and Venus, appeared to pass so close to each other that they would have briefly blended into a single bright star. Could one of these unusual planetary conjunctions have been the heavenly sign that launched the Magi on their journey westward to Jerusalem where they found the infant Jesus? Unless other ancient records are found that give us more and better clues, this is as good a guess as any that astronomers can make.
This Christmas season, Jupiter and Venus are close together once again in our evening sky. Watch them nightly this week as they draw closer together until, on the evening of Dec. 1, the crescent Moon will join the two brightest planets for an unforgettable conjunction at dusk. Don't miss it!