Jimmy Westlake's Celestial News column appears monthly in the Steamboat Today.
Find more columns by Westlake here.
Steamboat Springs Two thousand years ago, St. Matthew recorded that something extraordinary appeared in the sky over Bethlehem of Judea that heralded 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 might it have been?
A bright comet would have been noticed and recorded by sky watchers world wide, 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 occurred in 7 B.C. and the other in 2 B.C. Both these planetary groupings involved the planet Jupiter, considered to be the king of the planets. On the morning of June 17 in the year 2 B.C, 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 this 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, the red planet Mars is our Christmas star. Watch for it rising in the northeastern sky right beside the full moon tonight. Mars reaches opposition on Christmas Eve and will not be this close to Earth again until the year 2016.