<Deep space>

A review of "A Journey with Fred Hoyle" by Chandra Wickramasinghe.

In 2004 Chandra Wickramasinghe published "A Journey with Fred Hoyle: The search for Cosmic Life", which to me was something of a breath of fresh air, opening a door away from the rather hidebound ideas of the origins of complex organic molecules on earth in some sort of primordial soup, and away from the idea of random genetic mutations as the sole driver of the variations enabling natural selection. True or not, this book has the power to broaden our thinking.

Chandra Wickramasinghe tells us how he took a "first" in mathematics at Ceylon University, and then came to Britain in 1960 under a Commonwealth Scholarship to pursue postgraduate studies at Cambridge University. He elected to do a PhD in theoretical astronomy, for which he was placed under the supervision of Professor Fred Hoyle (later Sir Fred Hoyle). At that time Chandra was 21 and Fred was already 45, but so began a lifelong collaboration and friendship which survived Sir Fred's resignation from Cambridge in 1972 and Chandra's subsequent move to the chair of Applied Mathematics and Astronomy at University College, Cardiff, and which lasted until Sir Fred's death in 2001 at the age of 86.

This book contains a number of parallel strands. In the first strand we have interesting biographical details of Chandra, his wife Priya, and their relationship with Fred and Barbara Hoyle. There are also a few excursions into theories of planetary formation, the Viking missions to Mars in 1976, the fossil archaeopteryx, and the spread of influenza epidemics. There are threads relating to the development of computing power, and radio and visual astronomy. But above all this is a story about the search for the composition of interstellar dust.

On a first reading, if one does not know the final denouement, the composition of interstellar dust is not the most scintillating topic for a book. However Chandra weaves it into his biographical story in a way which makes it palatable for the lay reader. For example, as an avid fan of the Lake District, I found it fascinating to learn that Fred and Chandra discussed the nucleation needed for the condensation of ice particles, in relation to whether it might rain while they were on Bowfell in Cumbria in 1961.

However when one does know the final outcome, then this story of cosmic dust becomes wholly absorbing from its beginning, as one follows the development of the thought processes over many years, through to their startling final conclusion.

As a preliminary, Chandra tells us that the many interstellar clouds existing in this and other galaxies, are on the average about 10 light years across, and 300 light years apart, though there is considerable variation in this. At their most dense they still contain fewer atoms than the best vacuums that can be achieved by our laboratory vacuum equipment. Overwhelmingly they consist of hydrogen, but with varying proportions of the other naturally occurring elements. The commonest molecules present are (in order) hydrogen (H2), carbon monoxide (CO), formaldehyde (H2CO) and water (H2O). These molecules have been detected by observing the way that these clouds absorb or emit radiation.

As well as all these atoms and molecules, interstellar clouds also contain what Chandra describes as "an all pervasive and enigmatic dust component". This book is really a detective story about the identification of the composition of this dust, though it eventually goes far beyond this.

Chandra tells us that in 1961, when he started researching the dust, it was "almost an article of faith among astronomers that interstellar dust grains were composed of dirty ice material".

He showed quite soon that the wavelengths at which the dust absorbs light from distant stars (the absorption spectrum), combined with the nucleation problem (previously discussed on Bowfell), was not compatible with ice particles. It was though much more compatible with carbon particles.

Chandra describes the hostile reception he received from the proponents of the ice particle theory. Earlier in the book he had already noted his initial astonishment at discovering "the component of jealousy that entered a scientific controversy".

The story after that is largely one of the improving computing power available for the simulation of absorption spectra for various theoretical types of dust, improvements in the recording of the actual absorption spectra, including extensions into the infrared and ultraviolet wavelengths, and continual refining of the model.

This model gradually evolved from carbon particles (1961) through graphite/iron/silicate mixtures (1968), formaldehyde polymers (1974), cellulose (the most commonly occurring terrestrial biopolymer we are told) (1977), and culminated in the bold and startling conclusion of desiccated bacterial spores (1979).

So far so good, even though Chandra notes that here began the worst of all the hostility they received from the scientific establishment.

They did not stop here however. They examined the spread of influenza epidemics, and accumulated a measure of circumstantial evidence that the spread was by airborne viruses rather than directly from person to person. They developed a theory that cometary material contains bacterial and/or viral material, and that this percolates down through our atmosphere. Indeed such material has now been found high in the atmosphere.

In summary, they developed a modern theory of panspermia. It was not well received. Chandra quotes the editor of "Nature" in a 1986 article: "What these authors seem incapable of understanding is that their panspermia convictions sully even their sober contributions to the literature".

In some ways they did not help themselves. In 1982 Chandra had given evidence on the side of the creationists in a US court case about an educational syllabus. In 1985 they questioned the authenticity of the British Museum's archaeopteryx fossil. Even Chandra notes of this episode: "We did not convince our opponents ……. and we also lost many friends".

Chandra asks (page 182): "Why is there such deep rooted hostility to our ideas?" [when there is so much evidence for them].

Earlier in the book he had virtually answered his own question. In his very first chapter he notes that "at the deepest level, science, particularly when it comes to fundamental questions such as the origins of life, is inextricably linked to cultural traditions. Although subconsciously ignored or sublimated they remain as invisible constraints."

I would add that the western monotheistic traditions of Judaism, Christianity and Islam are wedded to a one-way course of history, which is conducive to big-bang theory, a single evolution up to man, and a single revelation from God. The eastern viewpoint is much more attuned to a steady state or oscillating theory of the universe. Panspermia is supportive of the latter viewpoint, not the former.

It does seem strange that, when we like to think of ourselves as objective scientific thinkers, such prejudices can still colour our thinking.

Many of the attributes of Wickramasinghe and Hoyle's theories of panspermia seem to be being increasingly accepted by the astronomical community. What is less clear (at least to me) is the extent to which any members of the biological sciences are working on any of it. It is commonplace that our cells contain a huge amount of so called "junk DNA", which is exactly what would be expected if panspermia is correct. Is any work being done, for example, on whether any of this might have originated from past exposures of the individual to viruses, or on the role that it might play in evolution?

There seems little doubt that panspermia has the potential to fill three gaping holes in the Darwinian theory, that is: 1. the initial origin of life on earth 2. the claim that random mutations alone cannot produce enough new genetic material and 3. the fact that evolution seems to go in jumps, as so few "missing links" have been found in the fossil record.

Chandra points out at the end of the book that it's five centuries since Copernicus displaced our Earth centred universe, but it's only now that we are coming to realise that the Earth may not be the centre for life either. He believes that future generations will take the cosmic quality of life as much for granted as we do the sun at the centre of the solar system.

This is undoubtedly a persuasive viewpoint.