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Nov-Dec 2017)
...the implications for humanity will be profound.
It could be even more important if we know that alien life in the form of microbes - bacteria and viruses - exist in our midst even now and continually rains down on our planet.
Such microbes may sometimes cause devastating pandemics of disease, but more positively they have the potential to augment our genomes and over long intervals of time unravel an ever-changing panorama of cosmic life.
In either case - whether as alien microbes
in our vicinity or
alien intelligence on distant
planets - the acceptance of the emerging facts of cosmic life will
mark an important turning point in human history.
...all spell out a single cosmic truth: Homo
Sapiens as a sentient species appears to be hard-wired to seek out
its cosmic origins, perhaps intuitively sensing that we are not
alone.
Ingredients crucial for life on Earth, including the simple amino acid glycine and phosphorus - key components of DNA and cell membranes - were recently discovered on Comet 67P/Churyumov-Gerasimenko.
These age-old questions have recently acquired a
new sense of urgency.
In 1995 Cambridge-based astronomer Didier Queloz together with Michel Mayor discovered definite evidence of planets outside our solar system.
The first of these so-called exoplanets orbited a star 50 light years away in the constellation of Pegasus. It was a giant planet with a mass similar to Jupiter located too close to its parent star for any life to be possible.
In 2009 NASA launched its orbiting Kepler telescope, which was specifically designed to discover planets that are the size of Earth.
The detection process involved tracking down minute blinks (dimming) in the star's light when a planet transited periodically in front of it during its orbit.
At present nearly 4,000 definite as well as probable detections of habitable planets have been made within only a very small sampling volume of our Milky Way.
Most of these planets orbit red dwarf stars that are on the average twice the age of our sun.
Extrapolating from the sample of present detections,
On many of these planets one might speculate that
life may have begun, evolved, and perhaps long since disappeared.
Over half a century ago Philip Morrison and Giuseppe Cocconi first drew attention to the possibility of searching the microwave spectrum of cosmic sources for intelligent signals and suggested particular frequencies as well as a set of potential targets.
The SETI program (Search for Extraterrestrial Intelligence) began tentatively in 1960 and was first supported by NASA, and later by a host of private or semi-private entrepreneurs.
Except for a single brief and mysterious "Wow!"
signal discovered in August 1977, there has been a deathly silence
across all of the prospective sources that have been scanned.
This may have been the thinking behind Russian billionaire Yuri Milner's 100 million dollar SETI initiative that was recently announced with much pomp.
Buying more telescope time, increasing the range of wavelengths, enhancing detector sensitivity and extending sky coverage have been argued as prerequisites if a breakthrough within a decade is to be achieved.
But a positive result from SETI would be contingent on the emergence and widespread dispersal of primitive life capable of evolving into intelligent creatures.
How often does this happen?
The dogma, in turn, can be traced back to the Greek Philosopher Aristotle (384-322 BCE) who proposed that,
Unfortunately, because of his stature as a philosopher, Aristotle's views prevailed and still prevail almost to the present day.
Experimental demonstrations against the validity of spontaneous generation have consistently been ignored, in particular, the 19th century experiments of Louis Pasteur showing that life at a microbial level is always derived from preexisting microbial life.
is a dark nebula in the constellation Orion. If we are all made of stardust, then we are also organically connected to the star systems of the Universe.
With calculations showing grotesquely low a priori probabilities for the transition from non-life to life, only two options remain.
The origin of life was an extremely improbable event that occurred on Earth (because we are here!) but will effectively not be reproduced elsewhere.
In that case we would indeed be hopelessly alone, or, a very much vaster cosmic system than was available on Earth, and a very much longer timescale was involved in an initial origination event, after which life was transferred to Earth and elsewhere by processes that the present writer and the late Sir Fred Hoyle proposed many years ago:
The essence of our theory of cosmic life is that the entire galaxy - perhaps the entire Universe - is one single connected biosphere.
Physical transfer involving exchange of
meteorites, comets, and dust with an intermingling of genes on a
cosmological scale is far more probable than independent life
origination events that are assumed in conventional science.
The closest terrestrial analogue to this latter situation exists for microbes exposed to the natural radioactivity of the Earth.
Quite remarkably, microbial survival under such conditions is now well documented. Dormant microorganisms in the guts of insects trapped in amber have been revived after 25-40 million years. And some species of bacteria have even been found to thrive in the interiors of working nuclear reactors.
All this goes to show that arguments used in the
past to discredit panspermia on the grounds of survivability during
interstellar transport are seriously flawed.
Where did the suite of genes coding for complex brain function come from?
They were not present in the ancestral squid or
in any other living form that existed on the Earth at the time. The
clear implication is that they came from outside the Earth -
external to terrestrial biology - part of the cosmic milieu of life.
The list of organic molecules present in interstellar clouds has increased dramatically in number since their first discovery in the 1970s, and also has their degree of complexity.
The first astronomical discovery showing interstellar (cosmic) dust to mimic closely the infrared absorption pattern (spectrum) of bacteria was made by Dayal Wickramasinghe and David Allen using the Anglo-Australian telescope.
Decisive evidence for complex aromatic and aliphatic carbon-based molecules (ring molecules and long chain molecules) now exists everywhere in our galaxy, and even beyond in galaxies as far away as 8 billion light years.
While all such data still tends to be interpreted avoiding "biology" with the suggestion that we may be witnessing exceedingly improbable "primordial soup-type events" on a cosmic scale, cosmic biology remains by far the most attractive logical option.
This is further evidence of panspermia in action,
the organic molecules in interstellar space being degradation
products of itinerant bacteria and viruses.
The Giotto mission showed clearly that the
prevailing theory that comets are dirty snowballs had to be
abandoned in favor of comets rich in organic molecules, and most
likely also containing viable bacteria and viruses.
Artist's depiction of microorganisms from outer space bombarding an Earth-like planet.
Many species of fermenting bacteria are known to
be able to produce ethanol from sugars, so the recent discovery that
Comet Lovejoy emits ethyl alcohol
amounting to 500 bottles of wine per second would appear to be a
clear indication that such a microbial process is operating.
Although the Earth was demoted from its privileged position of physical centrality in the Universe over 500 years ago (and not without anguish), the trend to regard life as being centered on our home planet has persisted almost to the present day.
But a paradigm shift with far-reaching
consequences is imminent now, and public support also seems to be
growing.
This data was acquired from relatively inexpensive projects that involve balloon flights to the stratosphere and recovery of in-falling cometary dust.
The first in a series of such experiments was conducted by the Indian Space Research Organization in 2001 and 2006 with staggering results, indicating an inflow of microorganisms at the rate of a tenth of a tonne per year.
It is obviously of the utmost importance that these experiments are repeated by independent bodies, but this has not happened.
More expensive and sophisticated investigations need to be carried out, even on the samples collected so far, if we are to prove beyond doubt that these microbes are unequivocally alien.
The sad truth is that funding for such vitally important experiments is well-nigh impossible to secure.
Compared with other Space Projects for solar system exploration, the budgets involved here are trivial, but the scientific and societal pay-off could be huge.
at the University of Peradeniya, Sri Lanka, 1981. The pair worked jointly for over 40 years
as influential
proponents of panspermia.
The evolution of life takes place not just within a closed biosphere on our minuscule planet Earth but extends over a vast and connected volume of the cosmos.
It is to be expected on this basis that the
emergence of intelligent life is a logical consequence of the same
process and must, therefore, be commonplace on a cosmic scale...
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