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4 of 4 people found the following review helpful:
4.0 out of 5 stars
We are stardust, 5 Jul 2002
I'll start by saying that the late Sir Fred Hoyle was one
of my heroes in my teenage years. Thus I have a soft spot
for the ideas he pioneered. There is an awakened interest in the heavenly bodies known as comets,
both popularly and scientifically. This is evidenced in the first
instance by the success of certain disaster movies and in the second
by a plethora of unmanned probes which are scheduled to meet with
various comets in the next few years. NASA's CONTOUR (Comet Nuclei Tour) will pass through the comas of Encke and Schwassmann-Wachmann 3
in 2003 and 2006. Deep Impact will, as the mission name suggests,
impact Tempel 1 in 2005 and Stardust is scheduled to sample P/Wild 2
a year later. The ESA plans to launch Rosetta next year, which will
rendezvous with comet wirtanen in 2011 and place one probe in orbit
and a second on the nucleus. As a race, our fascination with comets goes back possibly thousands
of years. They were often considered dread portents, harbingers of
doom; both feared and yet venerated. Wickramasinghe paints a picture
of comets as 'cosmic dragons' - in Western culture the dragon is an
evil creature, to be slain whenever possible, yet in the ancient
Orient the fearsome dragon was a terrible but beneficient power,
dispensing life-giving rain. Here, he shows how both these aspects
might apply to comets, ancient and modern. Much of what is written here the scientific establishment will
consider heretical. The whole notion of panspermia - essentially the
delivery of biological material throughout space by means of comets,
asteroids, and the like - is a shocking and challenging one.
However, covering ground from the late Sir Fred Hoyle's work on the
formation in supernovae of heavy elements and their delivery to
Earth, through the identification of organic material in comets and
interstellar dust, to the recent studies of cosmic dust by the
Stardust probe, Wickramasinghe presents a persuasive argument that
not only did carbon-based life originate in space, but that it was
brought here by comets, and that this process still occurs. Indeed,
he argues that many events in human history, including plagues and
the cyclic nature of ice ages, can be traced to regular approaches of
comets, both due to direct impacts and shed material reaching Earth. Wickramasinghe starts the book with some basic astrophysics and
biology. Although the treatment is necessarily brief, more detail
would have been welcome. The discovery that interstellar dust
consists of particles that strongly resemble bacteria is
perhaps the most compelling argument of the book - the evidence is
quite startling and it is surprising that these ideas are not more
widely accepted. He is less convincing when defending Hoyle's
quasi-steady state hypothesis of the Universe's generation,
especially in view of the body of evidence that favours the 'big
bang' hypothesis favoured by most cosmologists. The insistence on
the quasi-steady state model does detract from the soundness of the
panspermia argument, which is unfortunate because panspermia could
exist quite peacefully with the 'big bang' model. The major implication - if panspermia is true - is that the Universe
is teeming with life. If true then rather than the common view that
life evolved once, in an extremely unlikely event, on our little blue
and green oasis, Hoyle and Wickramasinghe's ideas mean that life will
be wherever we look, delivered by the comets that also destroy it.
The exciting thing is that (apart from the quasi-state state
hypothesis), the notion of panspermia is eminently testable, in time.
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