To add to all this misery, Enoch Powell had made his inflammatory 'rivers of blood' speech in Birmingham, igniting a race relations crisis. Meanwhile, in the U.S., Richard Nixon, already presciently regarded by many as a crook, was elected president.

Artist Michelangelo was commissioned by Pope Julius II between 1508 and 1512 to paint the ceiling of the Sistine Chapel. Here, God gives life to Adam

But then, in the early hours of Christmas Day 1968, 40 years ago, something almost magical happened that all but cancelled out the horror of the previous 12 months.

It's no exaggeration to say that the Apollo 8 space mission to the Moon, and what unexpectedly happened that Christmas Eve night changed the way humankind saw itself. Yet, surprisingly, the events aboard Apollo 8 didn't concern the Moon so much as the Earth itself, and our place on it.

Apollo 8 had set off a few days before Christmas. It was the most daring space mission ever, taking astronauts William Anders, Jim Lovell and Frank Borman further from Earth than humans had ever been.

Early on Christmas Eve, the craft reached Lunar orbit. The first Moon landing, by Apollo 11, would not take place for another seven months, but Apollo 8 was a test of whether the spacecraft worked. It did, and at 3am London time on December 25, the three Americans saw something never witnessed before; Earthrise from the Moon.

The astronauts grabbed a camera and took a series of colour photographs which went on to become some of the most iconic ever.

They showed Earth as a tiny blue, green, brown and white ball of incredible beauty, hanging in the blackness of space. It had no international borders, no politics, no races and, indeed, no visible sign at all of Mankind.

Anders, Lovell and Borman also pointed a TV camera out of their porthole and, although the fuzzy black-and-white pictures beamed back from space didn't have the impact of the colour photos we would later see, the men's broadcast gained what was then the biggest TV audience ever.

Theoretical physicist Albert Einstein: 'What separates me from most so-called atheists is a feeling of utter humility toward the unattainable secrets of the harmony of the cosmos.'

'The vast loneliness is aweinspiring, and it makes you realise just what you have back there on Earth,' Lovell told the watching billions over the crackles of static from a quarter-of-a-million miles away.

The 'you' Lovell referred to implicitly included everyone who was, at that time, at one another's throat - capitalists and communists, Americans and Viet Cong, Protestants and Catholics, police and protesters. And his point struck home on our tormented planet. It was a simple observation, but one which could be made only by the first people to see Earth from a distance.

Just as the astronauts were dependent on their frail spacecraft, we were all passengers on one vessel sailing through space. It was, in effect, a religious observation about humanity being one, united group. And then, providing a shock to the system I can still recall today, Anders' flat, controlled, testpilot voice announced that his crew had a message they would like to send us.

'In the beginning God created the heaven and the Earth. And the Earth was without form, and void; and darkness was upon the face of the deep . . .' he said. One by one, the men read the first paragraphs of the Book Of Genesis, with Commander Borman ending on 'and God saw that it was good'.

'And we close with good night, good luck, a Merry Christmas - and God bless all of you, all of you on the good Earth,' Borman concluded. Although the astronauts were not the most animated of men, it was still a stroke of theatre - from the timing to the execution - that you imagine Jesus himself would have enjoyed and appreciated.

Aged 13, and a huge fan of the Apollo astronauts, I lapped it all up - apart from the Bible bit. The Sixties were a scientific age. Religion was dead, wasn't it? What, I wondered, were my astronaut heroes doing with all that God stuff?

Believing in God seemed, to a Sixties child like me, as childish as believing in Santa Claus. Astronauts were test pilots, scientists at heart. How could they, of all people, believe in unproven, superstitious fairy tales about God?

I wasn't to know then that a lot of the astronauts were religious men, and plenty who weren't before they went to the Moon quietly became so after. Buzz Aldrin, the second man to walk on the Moon, secretly took Communion there using a kit given to him by the pastor at his Presbyterian Church. He admitted the fact only several years later.

And in the 40 years since Christmas Day 1968, I've learned that a significant number of scientists are also deeply religious.

It seems supremely paradoxical that people trained to accept nothing without the strictest evidence can believe in God without any proof apart from a few old writings to go on. But believe they do.

In the past, the physicist Isaac Newton, the electricity pioneer Michael Faraday and the mathematician Baron Kelvin were among many religious men of science. Indeed, it was faith in God that drove the rise of science in the 16th and 17th centuries.

Albert Einstein didn't quite believe in God, but didn't denigrate those who do. 'What separates me from most so-called atheists is a feeling of utter humility toward the unattainable secrets of the harmony of the cosmos,' he wrote.

Yet, at the same time as many scientists have quietly maintained a belief in God, atheism has continued to be in fashion for educated people around the world.

Militant atheists such as Professor Richard Dawkins of Oxford University, author of the influential book The God Delusion, have brought, ironically, a religious fervour and wrath to their 'preaching'.

Oxford University's Richard Dawkins, an evolutionary biologist, has spoken out against blind faith and the harmfulness of religion

So how, I've always wondered, do religious scientists explain their beliefs?

Perhaps it is the tough times we live through, perhaps just the inevitable questions you ask as you get older, but in the run-up to this Christmas and the anniversary of the Apollo 8 mission, I asked a variety of scientists how they square their work with their faith.

What united these men and women was a certainty that there is more to life than meets the eye, or even the electron microscope. All saw their role as scientists as one of exploring and experimenting with the natural world but, at the same time, always knowing that this world was the creation of a higher intelligence.

Surprisingly, I found them, like Einstein, more openminded and humble than the majority of their arguably more blinkered, hyper-rationalist, atheist colleagues.

For example, there is Professor Sir John Polkinghorne of Cambridge University, one of the world's most renowned particle physicists, a Fellow of the Royal Society, who became an Anglican minister when he retired from academia. 'Faith isn't a question of shutting your eyes, gritting your teeth and believing six impossible things before break-fast because some unquestionable authority has told you to. It's a search for truth,' he said.

'Science is great, but it's not the whole story. It deals with repeatable experience, but we all know that in our personal lives, experiences aren't repeatable. And you simply couldn't demonstrate how someone is your friend, or what music is.'

Moreover, he insists that there is no lack of evidence of God. 'I believe God reveals his nature in many ways. They're not demonstrations that knock you down, but they are very striking things about the world that are best understood as the work of God.

'The wonderful order of the world, which we scientists investigate, is a sign that there is a divine mind behind that order.'

Similarly, Oxford mathematics professor John Lennox argues: 'This misapprehension that faith is a religious thing not involved in science is simply false. I see the two as belonging together.'

The softly-spoken Ulsterman added: 'But science is limited. That's no insult to science, but as I recently told Richard Dawkins, I could dissect him, run his brain through a scanner, reduce him to chemicals and tell a great deal about him. 'But I'd never get to know him as a person. For that, he must reveal himself to me.'

Professor Lennox said that God has revealed himself at several levels, in the universe and creation.

'Science gives us pointers towards God, but you don't get proofs; you get evidence. And faith is evidence-based - not based on lack of evidence, as Dawkins says.'

So what, I asked, is the evidence? 'The evidence is cumulative and of two sorts - objective evidence that comes from science, and what I see in Jesus Christ who, as Christmas reminds us, is the Word become flesh, God encoded in humanity. 'The subjective side is my experience of God through Christ in my daily life.'

London and Oxford-trained biologist Professor Pauline Rudd, based at University College Dublin, is another Christian who successfully balances religious belief with scientific rigour.

Bristol University's Stuart Burgess, a mechanical engineer, says, 'The miraculous bright star which appeared over Bethlehem was an evidence of a special birth.'

'Science is a good system for understanding materials and material things, but there are plenty of things in life that don't fall into that category,' she said.

'Poetry, music, art, the love I have for my grandchild. Even if I could, I wouldn't want to weigh and measure that, or my relationship with my friends, or with the sunset.

'But equally, I do want the ideas I formulate about God to be consistent with my knowledge of science. So I've never needed to believe in impossible things. With miracles, for example, I would say most have a perfectly natural explanation.

'So if you took the Feeding of the 5,000, I'm sure there was enough food, but people just weren't generous enough to share it until someone started. Things like that moved people, and in those days they might have called it "miraculous".' So who or what, I wondered, was Jesus?

'I think he was a person in whom our highest ideals and values somehow emanate,' said Professor Rudd.

'What is opaque in most of us, in him was transparent. So love and power and courage and all the highest human values were expressed in him.

'To that extent, he was the expression of God in a way that almost nobody else has ever really been. But I think the idea of him being God was superimposed later and that's not what I believe. It's too simplistic.'

It was notable how these religious scientists balked at the more simple-minded 'creationist' views (the belief that the world was created in six days) that have been exploited by Professor Dawkins and his supporters.

'The creationists mistake the first chapter of Genesis for a divinely dictated piece of science,' said Sir John Polkinghorne. 'It's deeper than that. Its purpose is to say that nothing exists except through the will of God.

'The irony is that while seeking to be respectful to scripture, these people abuse it.'

Miracles, simplistic propaganda fodder as they may be to some sceptics, are less of a problem to Stuart Burgess, Professor of Mechanical Engineering at Bristol University.

'I'm not ashamed to believe in miracles,' he said. 'It is actually the claim that miracles are impossible which is anti-science because science should always be openminded. It is not just religious people who have faith without proof.

'Despite expensive equipment and the promise of the most famous Nobel Prize in history, no scientist has reproduced the spontaneous generation of life in the lab.

'As things stand, atheists must have faith the size of a mountain to believe that life arose without an intelligent designer.

'The mix of faith and evidence that a Christian has can be seen in the Christmas story.

'The miraculous bright star which appeared over Bethlehem was an evidence of a special birth. But the Wise Men had to have enough faith to take the risk of following the star all the way to Bethlehem.

'The most moving evidence for Christianity I have seen is when a person with a broken life puts their trust in the Lord Jesus and finds healing, peace and purpose.'

According to Professor Burgess, a spacecraft specialist who designed the solar panels of a £1.4 billion satellite: 'This is what the Christmas message is really about.'

END