Letter: Star of Bethlehem

Sir: There have been several astronomical explanations for the Star of Bethlehem. Johannes Kepler (1571-1630) suggested the star was a conjunction of the planets Jupiter and Saturn in 7BC (Saturday Essay, 19 December). In the present century alternative suggestions have included a comet or a nova.

None, however, fits the scant account of this event in the Gospel according to Matthew II: 2-12: "...the star which they [the Wise Men] saw in the East, went before them, till it came and stood where the child was..." A "star" travelling across the sky in this way and seemingly standing still over a particular terrestrial location cannot easily be reconciled with a nova, comet or planet.

There is a growing body of evidence to support a theory originally advocated by Victor Clube and Bill Napier that the history of our civilisation has been punctuated by episodes of cometary missile impacts. (See Clube and Napier, The Cosmic Winter, Blackwell Oxford 1990; F Hoyle and N C Wickramasinghe, Life on Mars: the case for a cosmic heritage, Clinical Press, Bristol,1997). Such events would have played a crucial role in the evolution of myths as well as religious beliefs.

An impact event of this type involving the explosion in the atmosphere of a small cometary missile occurred in Tunguska, Siberia, this century. The Russian newspaper Sibir of 2 July 1908 reported, from a vantage point some distance from the epicentre of the explosion: "Early in the ninth hour of the morning of June 30 a very unusual natural phenomenon was observed here. In the village of Nizhne-Karelinsk ... the peasants saw a body shining very brightly, indeed too bright for the naked eye, with a blue-white light... "

This bears comparison with a medieval account of a "fireball event", cited by Victor Clube, Bill Napier and Mark Bailey: "A very terrifying apparition and sign of wonder has been seen in Bamberg and Liechtenfels. In the year 1560, on 28 December, [this apparition] was seen in the sky which first had its beginning over Eberssberg in Franconia, and rose directly over Zeyl, and then from Zeyl [moved] towards the town call Elpmann ... and stopped still there for a long time."

Recent archaeological evidence from sites in Tunisia and Sweden points to an asteroid impact in the Middle East around 1000BC (British Archaeological Reports S728, 1998). This would accord well with Old Testament accounts of the destruction of Jericho, which are full of graphic descriptions of stones raining down from the skies, and where Joshua is said to have bid the sun to stand still in the sky (Old Testament, Book of Joshua). What Joshua must have seen was clearly not the Sun standing still, but the distant glow of an immense fireball. One might wonder whether the account in Matthew of the Christmas Star is an event of a similar kind, although smaller in scale and viewed at a safe distance of perhaps a hundred kilometres.

Several early Christian writers have referred to the extraordinary nature of the Star of Bethlehem. For example in the second century Ignatius of Antiochia in an Epistle to the Ephesians XIX wrote thus: "The star was so bright that its light was unspeakable and its newness caused astonishment ... a new star unlike any of the other well-known planetary bodies ..."

This might well have been another example of a Tunguska type event - a fragment of a comet approaching the Earth, entering the atmosphere and eventually exploding in the skies over the Middle East some distance away from Bethlehem. A cometary missile impact, of the kind that has punctuated history since the end of the last Ice Age, would then have heralded the birth of Jesus Christ.

On such a picture one would also expect a multitude of smaller meteoroids to follow the larger cometary missile. It is then easy to understand how the resulting spectacle of a great meteor shower came to be immortalised as a "host of angels".

Professor CHANDRA WICKRAMASINGHE

Cardiff