ray memorial lecture 2014: extra-terrestrial life and future trajectory of humanity

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The Discovery of Extraterrestrial The Discovery of Extraterrestrial Life – A Turning Point for Life – A Turning Point for

HumanityHumanity

Chandra WickramasingheChandra Wickramasinghe

Ray Wijewardene Memorial Lecture, 31 July 2014

The very first hominids are believed to have inhabited eastern Africa some 5-7 million years ago

From very recent studies in genetics and from the examination of ancient bones we have learnt a great deal about our immediate line of descent

Our hominid ancestors have roamed the the surface of the Earth for a very long time

The first modern humans walked out of Africa as hunter-gatherers only 70,000 years ago.

Graph Source: www.census.gov & www.wikipedia.org

When the last ice age ended about 11,500 years ago, total human population was about 1 million

Graph Source: www.census.gov & www.wikipedia.org

Now it is about 7200 million

After the end of the last ice age there were several crucial turning points in the history of civilization

Old Stone New Stone Bronze Iron Medi Age Age Age Age -aeval

Major turning points in the past 2000 years have been mainly related to technological innovation

1800’s

Steam train

Printing press

Farming

Egyptian plough, 1500BC

Chinese plough 1639AD

The very earliest technologies were devoted to improving agriculture and food production

Horse-drawn mediaeval plough

Steam-drawn nineteenth century plough

The mediaeval heavy plough transformed the world - enabled heavy clay terrain to be tilled and cultivated and this greatly enhanced food production

From horse-drawn and steam-drawn ploughs to the 20th century 4-wheel tractor plough was a big step forward

It is in this context that I think Ray Wijewardene’s two-wheel tractor/plough should be evaluated, for it helped to transform agriculture in the developing world

Our earliest attempts to comprehend the Our earliest attempts to comprehend the world around us are buried in the mists of world around us are buried in the mists of antiquityantiquity

Our capacity to represent the cosmos, Our capacity to represent the cosmos, whether in art or literature or science, sets whether in art or literature or science, sets us humans apart from all other creatures us humans apart from all other creatures that inhabit our planetthat inhabit our planet

This amazing sight must lead naturally to questions that would have been asked from time immemorial

“How do we, humans, on this tiny planet fit into such a grand scheme of things?”

“How did the universe begin?”

“Where did we come from?”

For thousands of years our paleolithic ancestors would have gazed at the spectacle of the Milky Way, comprised of hundreds of billions of stars arching across the night sky

Attempts to answer such questions fell successively within the remits of

•Superstition and religion•Philosophy•Science

The most ancient attempts to connect with the cosmos are to be found in extant cave paintings (Pleiades and the Constellation Taurus in Lascaux cave in France - 16500-13000 BC)

And this continued into modern art as seen in Paul Guaguin’s 1897 painting with the title: “Where do we come from? What are we? Where are we going?”

•The scientific question I wish to explore in this lecture is this:

•Did life originate on the Earth in “some warm little pond”, or did it arise in the context of a vast Universe?

•The answer to this question has, for a very long time, been the subject of a cultural, geographic, and scientific divide....

The Greek Philosopher Aristotle proposed that life emerged from the inanimate stuff of the Earth

• He stated that fireflies emerge from a mixture of warm earth and morning dew, and variants of this idea dominated Western Philosophy for centuries

• Life was held to be Earth-based and Earth centred and any dissidents were severely punished

Aristotle (384 – 322 B.C.)

Giordano Bruno (1548 – Giordano Bruno (1548 – 1600)1600)

Who declared there Who declared there must be must be "an infinite "an infinite number of suns with number of suns with

planets and life planets and life around them“ around them“ was was

tried by the tried by the inquisition and burnt inquisition and burnt to death for heresy to death for heresy

Temple of Enlightenment, Mahabodhi Temple, Bodhgaya

In sharp contrast, Buddhist and Hindu philosophy took the view that life was a cosmic phenomenon

And Buddhism included what I consider to be the correct relationship between humans and the rest of the Universe……

“As far as these suns and moons revolve, shedding their light in space, so far extends the thousand-fold world system. In it there are a thousand suns, a thousand moons, a thousand inhabited Earths and a thousand heavenly bodies. This is called the thousandfold minor world system….”

The cosmological philosophy of Buddhism is nowhere better summarised than in the following statement, written a full 1500 years before the West had shaken away the concept of an Earth-centred Universe….

About 300 years after the Buddha, the Greek philosopher Aristarchus of Samos (310-230BC) discussed the idea of life as a cosmic phenomenon, and it was entirely possible that he was influenced by Buddhist thought

Aristarchus proposed Aristarchus proposed that living seeds that living seeds ((spermataspermata) are ) are distributed throughout distributed throughout the cosmos the cosmos – – panspermiapanspermia

This is the idea that I This is the idea that I developed scientifically developed scientifically over the past 40 years, over the past 40 years, a theory that is about a theory that is about to break through into a to break through into a major scientific and major scientific and cultural revolutioncultural revolution

The first is a discovery originally made by Pasteur in 1870 that microbial life is always derived from pre-existing life

He showed that processes such as the fermentation of wine, and the souring of milk did not occur in the absence of pre-existing microbes

Louis Pasteur (1822-1895)

The logic of panspermia follows from two unarguable facts

The second is the ability of microbes to survive the extreme conditions of space, to which I shall return later

Present day life forms

Fossils

Metazoan explosion

Oldest evidence of microbial life on Earth from 3.83- 4 by, at a time of severebombardment by comets and asteroids

Primordial soup?Altermative: Life from Life logic leads to a cosmic origin

Pasteur’s life from life logic leads to panspermia

Aleksandr Oparin (1894 – 1980) J B S Haldane 1892 –1964),

The conventional wisdom is the Earth-bound primordial soup theory, for which there has

never been much empirical support, and now there are grave objections that essentially

rules it out

Life first appears on Earth during, or shortly after, the period of heavy bombardment by comets….. Strongly suggesting that comets carried this life

• Another objection relates to the molecular complexity of life that defies understanding on the basis of an Earth-based origin

• As soon as biochemists discovered the super-astronomical complexity of living systems at a cellular and molecular level, the cosmic quality of life becomes almost self evident……..

• Here is a computer simulation of how a living cell replicates

It is scarcely conceivable that the exceedinglyy specific arrangements of monomers needed

for even the simplest living cell can be produced in a diminutive warm little pond on

Earth,

Nor is there any logic that demands this. - the Earth is not a closed system sealed from

external cosmic contaminants

I shall argue now life on Earth is the result of an I shall argue now life on Earth is the result of an evolutionary process that has taken place on a vast evolutionary process that has taken place on a vast

cosmological scalecosmological scale

The earliest beginnings of these ideas were in fact expounded here on 27 April 1982 in a lecture entitled “Is Life an Astronomical Phenomenon?”

32 years ago this was a question to be explored

• By 1992, astronomers were agreed that the dust clouds in interstellar space contained organic molecules and supplied the raw material from which life could originate – but the origin of life itself was considered to be a purely terrestrial affair!

Evidence for the actual connection between interstellar dust and life itself began to grow from the mid 1980s

Implies: 1 carbon atom in 3 is tied up in a form not distinguishable from freeze dried bacteria

SBS 0909+532

An absorption signature of dust similar to biological aromatics was discovered at a distance of nearly 8 billion light years, at the very edge of the observable universe – and similar data continues to flood in

•A crucial component of our case for cosmic life are the Comets

•Traditions that comets were bringers of life as well as pestilence and death are deeply ingrained in human culture

•It will turn out that in many crucial respects these ancient views might be valid

Since 1986 space probes have made close approaches to many comets and confirmed the existence of organic molecules, as well as dust

that is life-like

Comet Borrelly

It is now clear that comets represent the oldest condensed material that connect our planetary system with the earliest stages of the Universe

The Oort Cloud comprised of 100 billion comets surrounds the entire planetary system

43

Since the1986 studies of Comet Halley, comets have been confirmed to be life-like in composition

44

In 2004 Stardust spacecraft actually sampled the from coma of comet Wild 2 ’s

45

Comet particlestrapped in theAerogel were returned to Earth

•Glycine•Residues of biochemicals surviving impact•Clay minerals, cubite

46

•Images of Comet Tempel-1 taken with cameras aboard Stardust showed water jets, organics, and evidence of organic rich subsurface lakes

ESA’s Rosetta Mission to comet 67P/Churyumov-Gerasimenko – rendezvous later this year

•Comet sweating 300 ml/second in cold depths of space shows that life processes have begun

•In the rest of my lecture I shall assume that comets are repositories, incubators and deliverers of cosmic life

Comet Tempel 1

Earth Orbit

73P Schwassmann-Wachmann3, fragmenting in 2006

The mechanism of panspermia within our solar system involves the release of life-bearing material from comets

Earth’s orbit is in fact enmeshed in debris of comets – that sometimes include pieces of extinct comets

Earth’s orbit

•Can a biological component in comet material be discovered by present-day experiments, and so prove our cosmic origins?

About 100 tonnes of such cometary debris falls through the stratosphere daily – most, but not all of it burns up as meteors

Occasionally large pieces of an extinct comet falls to Earth in tact and can be studied in the

laboratory to see if there are signs of life

Eg. the Murchison meteorite, which fell near the town of Murchison, Australia on 29 September 1969

H.D. Pflug in 1980 used thin sections to study the contents of this meteorite

•Thin sections, placed on a till, and HF used to leach out the minerals

•Organic structures were left in tact on the membrane that was then examined under electron microscopy

Structures in Murchison compared to recent microbe Pedomicrobium

Structure in Murchison compared to inset of influenza virus

Tobacco Mosaic Virus

Pflug – Murchison MORE

VIRUSES!

In 2001, in collaboration with ISRO, we collected infalling cometary dust, gently, before it became

mixed with terrestrial contamination

The air from 41km revealed signs of microbial lifeViable but non-culturable microorganisms indicated by the use of fluorescent dyes

Clump of cocci and bacillus

Nanobacteria

Implicated in atheroscleroses and human kidney stones?

•Height of 41 km too high for lofting microbes from Earth•Daily input of microbes is 0.1 ton per day, over the whole Earth

In July 2013, in collaboration with Milton Wainwright of Sheffield University, we collected meteoroids that

fell through the stratosphere to 27km

A weather balloon lofted to 27km was designed to capture infalling particles directly onto electron microscope stubs

Particle collector

The stubs were carefully recovered under aseptic conditions and examined under the electron microscope

There were microcraters from particles that struck at ~5-6 km/s – proof of incidence from above, not lofting from below

Biological structures – clumps of nanobacteria

Biological filaments within a 200 micron dust clump

A collapsed balloon-like biological entity sampled from the stratosphere. Note “proboscis” to the left, with nose-like openings and the “sphincter” at the top

A strange case of titanium-coated microorganisms

Micromanipulator needle used to lift

Titanium shell

Organic ooze

Even more dramatic and compelling biological find was a fragment of a diatom frustule perhaps belonging to the group Nitzschia

It is a remarkable instance of serendipity that perhaps the most compelling evidence of extraterrestrial life was discovered near Polonnaruwa in December 2012, at a site which has since been declared by President Mahinda Rajapakse to be a national heritage site

Site of meteorite fall on 29 December 2012

Fall happened after fireball sighting on 29 Dec 2012Estimated 100 kg of meteorites distributed over 1 square km area

Farmer Tikiri Banda picks up piece with fusion crust in January 2013

•Very porous, low density - unusual nature compared to most other meteorites sparked controversy – now mostly resolved•Most likely origin - fragments of the porous outer crust of a comet

A variety of marine diatoms discovered

Also “acritarchs” – life-form extinct for billions of years

Acritarchs

Diatoms

All these structures cannot be dismissed as either artefacts or contaminants, for various technical reasons.

• The ratios of stable oxygen isotopes 16O,17O, 18O were determined, and found to be inconsistent with a terrestrial origin.

• Analysis of trace elements in the bulk composition of the meteorite has yielded high abundances of the element iridium. at levels of 7-8 parts per million

• Such iridium levels found in sediments at the K/T boundary have been used to argue for a comet impact

• All this constitutes a major affront on conventional biology, and it is natural to spark controversy

A FEW TECHNICAL POINTS...........

So far we have discussed bacteria and diatoms as alien cellular invaders

Viruses are likely to be overwhelmingly more important in the scheme of things

10 million viruses have recently been counted in a single drop of sea water

Since these viruses degrade on a short timescale, they must be falling into the oceans in the rain

•There are an estimated 1031 viruses on Earth. That is to say: there may be a hundred million times more viruses on Earth than there are stars in the universe.

•Viruses make up the bulk of the mass of the entire terrestrial biosphere

•They are difficult to detect in the environment except when they cause diseases in plants and animals

•Their capacity to survive under space conditions surpasses that of even the hardiest bacteria

Viruses are the most efficient transmitters of genes between species on Earth, and across the cosmos

Two facts are becoming increasingly clear with the march of modern science – The astronomer’s universe is incredibly vast and complex in its structure

In February 2001 the human genome was fully deciphered – and ancient relics of viral genes were found

Recent studies have shown that over 50% of the human genome is made up of viral sequences

And these viruses were inserted into our ancestral line through

devastating pandemics of disease

Our DNA carries the history of past pandemics

• The evolution of hominids over a million years was marked by a succession of pandemics from space, each of which was a close call to total extinction

From what we have seen, there is no doubt that alien microbes, alien genes, have bombarded Earth for 4 billion years, and continue to do so even at the present time

Moreover, such cosmic genes, over millions of years, have made us what we are

• Life originated in a cosmological context, and was delivered to Earth by comets

• Evolution involved the addition of new viral genes, selected against the criterion of natural selection - survival of the fittest

• Genes– after countess acts of re-cycling - are derived gratis from the cosmos, a far vaster and more varied setting that anything we have on the Earth

Answers to Guaguin’s questions now emerge: Answers to Guaguin’s questions now emerge: Where do we come from? Where do we come from? From the cosmosFrom the cosmosWhat are we? What are we? Assemblages of cosmic genesAssemblages of cosmic genesWhere are we going? Where are we going? Back into spaceBack into space

•Why, despite all this compelling evidence, is the conclusion of cosmic life being resisted in some circles ?

Answer: Culture, religion, innate scientific conservatism

•The long overdue paradigm shift from Earth-centred to cosmic-centred life is an extension of the Copernican revolution which started nearly half a millennium ago

Geocentric universe

Heliocentric universe

The original Copernican revolution lasted 150 years

Today, an extension of this same revolution may be stalled for apparently rational reasons :

• The admission of extraterrestrial life might be perceived as a threat to national security. People may become so scared and emotionally so unsettled that even the enforcement of law and order might pose a problem.

• To admit that we have supported a wrong paradigm may also have economic repercussions in regard to the large funding commitments already in place for exploring ideas based on a totally false premise.

Then there is the issue of cosmic viruses and pandemic disease

The recognition that alien viruses are raining The recognition that alien viruses are raining down on us and are an ever-present threat down on us and are an ever-present threat

may necessitate expensive surveillance may necessitate expensive surveillance programmes to monitor the stratosphereprogrammes to monitor the stratosphere

The 1918-1919 influenza pandemic killed 20 million

The discovery of a nearby planetary system The discovery of a nearby planetary system with signs of life upon it may justify the with signs of life upon it may justify the

planning of space missions to such a distant planning of space missions to such a distant place at very great expenseplace at very great expense

Perhaps the worst casualty of all will be Perhaps the worst casualty of all will be our self-image as the supreme lifeform in our self-image as the supreme lifeform in the cosmos, which will be shattered and the cosmos, which will be shattered and require major efforts in psychological and require major efforts in psychological and educational readjustment. educational readjustment.

It is likely that the entire structure of human society will undergo a transformation more fundamental and profound than any that has taken place so far.

Over tens of thousands of years the Over tens of thousands of years the smallest unit to which loyalty is owed has smallest unit to which loyalty is owed has expanded ....expanded ....

from the nuclear familyfrom the nuclear family to the extended familyto the extended family

the small tribethe small tribe

Over tens of thousands of years the Over tens of thousands of years the smallest unit to which loyalty is owed has smallest unit to which loyalty is owed has expanded ....expanded ....

the city statethe city state

the nation statethe nation state

Over tens of thousands of years the Over tens of thousands of years the smallest unit to which loyalty is owed has smallest unit to which loyalty is owed has expanded ....expanded ....

to all of humanity and to some extent to all to all of humanity and to some extent to all life that shares our biospherelife that shares our biosphere

The next transition must be to a full The next transition must be to a full recognition that we are all part of a vast recognition that we are all part of a vast cosmic living system cosmic living system

A new cosmic consciousness would surely A new cosmic consciousness would surely dawndawn

In conclusion - I believe that the fact of In conclusion - I believe that the fact of extraterrestrial life, and of our continuing extraterrestrial life, and of our continuing connection with the cosmos will become as connection with the cosmos will become as obvious to our grandchildren and to future obvious to our grandchildren and to future generations, as the sun being the centre of generations, as the sun being the centre of the solar system is obvious to us today.the solar system is obvious to us today.

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