Forget trying to count the number of angels on the head of a pin - there's an even more critical theological question weighing on the minds of Vatican astronomers: did God create little green men?

In an interview published today in the Vatican newspaper L'Obsservatore Romano, Reverend Jose Gabriel Funes, the Vatican's chief astronomer and scientific adviser to Pope Benedict, said that there's no conflict between the Christian faith and the existence of extraterrestrials.

But the idea that there might be intelligent life beyond Earth doesn't easily fit into the Christian worldview. According to the Bible, God created Earth as the centre of the universe and men in his own image. Would the Good Book's credibility be compromised by the discovery of alien life? I can just imagine the higher-ups at the Vatican pacing nervously as SETI began searching the sky for ET signals and surveys turned up planet after planet outside the solar system - some of which might be able to host life.

In a clever manoeuvre, the Vatican has pre-empted the threat an alien discovery would pose to Christianity. Now they say they won't be the least bit surprised should we make contact with our "extraterrestrial brothers".

And why should they? According to Vatican astronomer Guy Consolmagno, the Bible is chock full of references to aliens. In Intelligent Life in the Universe, published by the Catholic Truth Society in 2005, Consolmagno wrote:

"There are, unquestionably, nonhuman intelligent beings in the Bible. At least one group of such creatures is familiar to us all: angels. But are the 'holy ones', those 'in the sky', the 'morning stars', and 'heavenly beings' mentioned in Psalms and elsewhere references to angels? Or do they refer to some other kind of life beyond our knowledge?"

"If you're really eager to find a reference to extraterrestrials in the Bible," he writes, "you can't do better than John 10:14-16. 'I am the Good Shepherd . . . I have other sheep that do not belong to this fold. I must bring them also . . . so there will be one flock, one Shepherd.'"

Other sheep? Aliens, obviously! And it sounds like they are on their way.

The existence of ET life does leave Consolmagno with some head-scratchers. Are they burdened with original sin? Is there a "cosmic Adam" that predates his Earthly clone? Does one baptise an alien?

When little green men finally make themselves known, the Christians will be ready for them. After all, as Consolmagno says, "Having a soul has nothing to do with how many arms or legs or tentacles you have."