PLEASE NOTE:
*
THE BULLET THEORY: A NEW LINK BETWEEN MASS EXTINCTIONS AND ITS
IMPLICATIONS
FOR HUMANKIND
>From Michael Martin-Smith <lagrangia@lagrangia.karoo.co.uk>
Benny,
About 2 years ago, I wondered, in my rather amateurish way,
whether Impacts
and Volcanism could be tied together as causes of mass
extinctions, and,
inspired by "The Day of the Jackal", proposed a linking
theory, which I
dubbed the "Bullet Theory". I had a letter published in
the UK Journal
"Geology Today" in the summer of that year, and
emboldened by this,
submitted an article - see below - to Scientific American, both
its US and
Chinese (Ke Xue) versions. The concept was perhaps rightly
considered too
speculative at the time - but maybe the time has now come for it
to be put
before a learned if eclectic audience? Perhaps it would now
interest members
of our Network?
The Bullet Theory - a new link between Mass Extinction Events,
and its
implications for Humankind?
by Dr Michael Martin-Smith, BSc MRCGP, FBIS
Jesmond, Salisbury St HULL HU5 3EU, England
The Bullet Theory proposes a link between two widely held
explanations for
the demise of the dinosaurs, and, possibly, other Mass Extinction
Events.
Briefly, these are the Asteroid Impact theory, and the
Volcanism theory.
The asteroid impact theory holds that an asteroid of
about 10 kilometres
in diameter hit the Earth at 30 kilometres per second, and,
in addition to
creating a massive fireball, worldwide scattering of superheated
rock and
mantle, caused secondary firestorms, and Earth waves with 500
kph. winds;
also, by raising cubic kilometres of soot and dust into the
stratosphere,
the impact produced, as a secondary effect, global climatic
change lasting
for many years, accompanied by acid rain, lowering oceanic pH by
at least
one unit . Large animals and marine micro-organisms alike were
decimated by
these changes, and , in the case of some 85 % of terrestrial
species, mass
extinction occurred - with 99.99% of individuals ( Carlisle,
Alvarez, and
many others).
This theory is now well buttressed by many lines of evidence
1/ At over 120 sites worldwide, an anomalous layer of Iridium- a
metal rare
in the Earth's crust, but common in asteroids and early solar
system
material, has been found, at the relevant date of 65 million
years ago.
2/ At these sites, Cretaceous life is found right up to the
boundary layer
of Iridium, and none in the layers corresponding to thousands of
years after
the event. The change in chalk depositing organisms (
Foraminifera) is sharp
and beyond doubt.
3/ In this same Cretaceous/Tertiary layer (or K-T Boundary) a
layer of
fossilized soot is found world wide, due to global firestorms.
4/ The discovery of a massive 180 kilometers diameter crater in
the Yucatan
Peninsula in Mexico - Chicxulub - dated at 65 million years ago,
demonstrates beyond doubt that this impact took place, produced
global
effects, and that it was contemporaneous with the K-T Mass
extinction event.
5/ The discovery of 150 significant craters on this planet, and
thousands
more on all solid surfaces in the solar system shows that
impacts are a
factor in the evolution of Earth and other planets.
6/ The confirmation of at least 10 major extinction events in the
past 590
million years attests to the frequency calculated by
projected numbers of
impacts based on estimated numbers of near Earth Objects of a
range of
sizes. It is only the recycling of the Earth's crust by Plate
Tectonics, and
the effects of wind and water, which disguises the fact that we
are as much
a shooting gallery as the Moon or Mercury!
7/ The calculated effects of fireball, winds, and global
atmospheric changes
are now not a matter for speculation - they have been observed,
by 500
million viewers, at Jupiter, where the 21 fragments of Comet
Shoemaker-Levy
9 in July 1994 gave us a graphic demonstration.
There is thus no doubt that an extraterrestrial impact of
sufficient size
and energy to cause mass extinction hit the Earth 65 million
years ago, with
the calculated results - and that it was not unique.
The Volcanism Theory holds that , while the mass extinction
occurred at the
time stated earlier, and that others have occurred, the proximate
cause was
purely terrestrial - namely surges of widespread volcanism caused
by the
movements of the Earth's crust, in the theory known as plate
Tectonics. This
theory states that the continental crusts of the Earth's surface
float upon
the underlying magma of basalt, and are constantly moving -
pushed by the
upwelling of molten lava from sub-oceanic crustal fissures. This
material
spreads out and the overlying continents drift apart. Of course,
at the
opposite ends of these plates,. material must be re-absorbed, or
else the
Earth would simply become bigger over time - a concept which has
no
foundation at all!
Plate Tectonics, advanced originally by Alfred Wegener in 1911,
received
sound experimental backing in the 1960's, with the voyages of
Glomar
Challenger and the direct observations of the sub-oceanic
production of new
crust using submersible remotely controlled vehicles such as the
Alvin. The
measurement and dating of fossilised magnetic field lines in
ocean floor
samples showed that nowhere is the crust more than 200 million
years old,
and that the continents are indeed moving in relation to each
other.
Notably, the mid Atlantic Ridge is the site of volcanic crust
creation, as a
result of which Europe and America are moving apart consistently
at several
centimetres per year.
By contrast, the entire Pacific Rim is the site of the opposite
phenomenon,
whereby a spreading plate is pushed underneath the neighbouring
continental
plate - thus the Pacific plate tucks down into the deep Ocean
trenches, and
is enfolded deeper into the Earth's magma. In doing this,
pressurized water
is taken in with it, and , together with molten magma, finds its
way through
chambers in the overlying continental mass. The result is a ring
of active
volcanos all around the Pacific Rim , known popularly as the Arc
of Fire.
Thus surface material is continually being recycled over
geological time,
and the shapes and relative positions of the continents is in
flux.
This mechanism also accounts for earthquakes and tremors as the
sideways
slippage and shearing of neighbouring plates.
Geologists point to periods of intense volcanism as possible
causes of mass
extinctions. They, too, postulate similar mechanisms-
darkening and cooling
of the climate by volcanic dust and ash, acid rain from exhaled
carbon and
sulphur dioxides, and violent earthquakes.
They, too, have a candidate for the K-T event - namely the high
volcanic
plateau, of Southern India, known as the Deccan Traps. This, too,
is dated
at around 65 million years ago, and attests to an intense period
of
volcanism over a 1 million years period. Plate tectonics also
show that
India has been in movement Northwards and Westwards over the past
70 million
years, as shown by the build up of the Himalayas from subsurface
uplift as
India "crashes" into Asia.
Thus both events-- the Impact, and the Deccan Traps volcanic
events --
certainly happened at the relevant time. Carlisle points
out, however, that
in terms of amounts of basalt outflow per year, our own times are
as active
as the time of the Deccan Traps, and that there is not now an
ongoing mass
extinction event - unless we ourselves are the cause.
There is also the fact that volcanic eruptions do not spread
Iridium
worldwide, since this material has largely sunk into the core by
differentiation at an early stage in the Earth's history.
There is thus emerging something of a conflict of causes backed
by two very
different scientific traditions - Geological Uniformitarianism,
and
Astronomic neo-Catastrophism. Bound up with these is the classic
gradualism
of Darwinian Evolution, versus the Punctuated Equilibrium or
Cladism of
Niles Eldridge et al.
We thus have two mechanisms for the K-T Mass extinction event,
backed up by
plausible theory and sound observations. Can they both be
correct?
A New Synthesis
1/Where were India and Mexico 65 million years ago? If
diametrically
opposite, a new scenario emerges.
2/ Apollo descent engines, allowed to fall onto the Moon, caused
a gong like
ringing effect detected by seismometer packages for over one hour
later. The
Moon has a small core and no plate tectonics.
Could Earth, with a differentiated surface, transmit impact
generated waves
globally through its crust and magma? If so they would come to a
focus 180
degrees from ground zero. Thus the Chicxulub impactor could have
set up a
resonance which would initiate or amplify the Deccan Traps
events, by
creating cracks in the crust overlying the molten magma.
3/ It is well observed in ballistics and pathology that a high
velocity
modern rifle causes a bigger wound at the opposite side of a head
from its
entry point. The famous test run of the assassin's high power
light-weight
rifle in the film, "The Day of the Jackal", shows well
how the entry energy
can be amplified. A NEO comes in at 30-60 times faster than a
high velocity
bullet. There is no suggestion here that an NEO would exit at 180
degrees
from impact, but the shock waves would be focussed and amplified
with
catastrophic results at that point.
Co-ordinates of Chicxulub and the centre of the Deccan
Traps 65 million
years ago1
Present Day 65 million years ago
Longitude Latitude Longitude Latitude
Chicxulub 87°W 200 N 84° W 200 N
Deccan Traps 75-80° E 13-200N 95° E 210 S
Thus, to within one degree - quite reasonable, considering
the several
degrees covered by the volcanic outflows of the Deccan Traps,
these two
phenomena - the crater and the Traps - are exactly antipodal,
consistent
with the "bullet" theory.
An earlier Permian mass extinction , on an even bigger scale (95%
of all
species) at 250 million years ago, is blamed on the Siberian
Traps - a
similar even more massive series of volcanic outflows. It would
be
instructive, to say the least, to determine where, in Latitude
and
Longitude, on the Permian Earth the Siberian Traps were located,
and
whether, at the corresponding Permian Antipodes, an impact crater
is to be
found!
On Feb 22 2001, it was announced that "buckyballs"
filled with gases in an
isotope distribution, compatible with a cometary origin rather
than
terrestrial origin, have been found at various sites containing
Permian/Triassic deposits suggesting that the Permian mass
extinction was
comtemporaneous with an impact by a comet some 11 kilometres in
diameter;
the impact crater, having occurred in the now lost continent of
Gondwanaland, is nowhere to be found. More recently still,
Professor Kunio
Kaiho et. al of Tohoku University have published evidence,
in Geology,
that a massive impact DID occur at the Permian/Triassic junction.
An interesting case was found on the planet Mercury 2 by the
Mariner 10
spacecraft in 1974; the massive 3.85 billion years old impact
basin, the
Caloris region was formed by a 150 kms. impactor, leaving a
current 1385 kms
diameter basin. At the exact antipode, a large region of jumbled
hills and
depressions which has no precise counterpart elsewhere in the
solar system
was found; this region, the size of France and Germany combined,
is ascribed
to a concentration of shock waves emanating from the Caloris
Basin impact.
Mercury, unlike the Earth, has no active volcanism or tectonism
within at
least the past 3 billion years, so that a putative result from
the
postulated "bullet" effect could be expected to look
different; but it is
interesting to note that the idea of an antipodal effect is borne
out.
Some Implications
It is clear from the foregoing that at least two - possibly
linked -
mechanisms for Mass extinctions operate on this planet, and have
done so
throughout the geological time scale. In the worst event - the
Permian -
almost 95% of all species were extinguished, and the evolution of
Life
undoubtedly took a new turn.
Looking at human civilization, we may, at first sight, see little
relevance.
However, our civilization, especially the recent post Renaissance
liberal
technical civilization which has so far nourished, educated, and
medicated
more people in greater comfort than any of its 30 or more
predecessors, is particularly vulnerable to events of the kind
under
discussion. There are, simply, more people to kill and more
property to be
destroyed. We are, indeed, hostages to our own success. Indeed,
events on a
far smaller scale would suffice to plunge us back to the Stone
Age, or
worse, with billions of dead, and trillions of dollars of ruined
infrastructure. For instance, many authorities consider that the
threshold
size for an incoming NEO for the wreckage of civilization by
global climatic
change is about 1 kilometre, in contrast to the 10 kilometers
postulated for
the Cretaceous/Tertiary Boundary Event. The fact that such
an object has a
two in three chance of landing in the Ocean gets us not much
further, since
a series of tsunamis several hundred metres high racing
around the world at
hundreds of kilometres per hour does not inspire cheerful
thoughts, either A
similar scale reduction doubtless applies to the volcanic
scenario favoured
by many geologists.
We have seen that, in both cases, firestorms and global cooling
through dust
and soot deposition into the stratosphere would find many more
victims,
since, at best, there is but 3 weeks food supplies in reserve on
this planet
at any one time while a "Winter" effect would be
expected to last 6-12
months with a single Impact event, and probably far longer in the
event of a
volcanic Traps formation event! Following such devastation and
impoverishment, of our species, the emergence of pandemics of
new, mutated
viruses, or the release of pre-existing but poorly understood
species like
Ebola and Marburg, by dispersal of dust, and a change of animal
vectors
following the disruption of the biosphere , would be likely to be
something
of a coup de grace. It is widely accepted that the emergence of
such viruses
into the light of day from remote jungle sites has much to do
with changing
patterns of migration and social change, with accompanying
deforestation and
new transport infrastructure.
One can also confidently expect the re-emergence of another old
"friend"-rat
borne plagues- since, small mammals would be more likely to
survive such a
catastrophe, because of easier shelter, and the abundant presence
of carrion
for feeding. They also have rapid breeding cycles. In
addition to this, as
we have seen in recent natural disasters, epidemics of typhoid,
dysentery
and malaria put in an appearance as well..
The likelihood of a Humanity, already devastated by fires,
earthquakes,
cold, and starvation being able to mount much of an response to
these new
threats is at best minimal, and lessened by the inevitable
breakdown in
order and infrastructure which would accompany the disaster.
In short, without radical measures, taken in good time, the
prospects for a
longterm sustainable human civilization, on Earth alone, are
essentially,
zero. It is fashionable for many environmentalists to
advocate a
sustainable civilization based on less science and technology
than we are
used to. Quite apart from such a solution requiring coercion and
restrictions on a global scale far beyond any dreamt of by this
century's
crop of totalitarian despots, there is no prospect of success
therein.
What is to be Done?
To deal with any threat three things are needed. Prediction,
Reconnaissance,
and Effective Countermeasures.
It has been shown that at least three scenarios -
asteroid/cometary impacts/
massive volcanic activity in the shape of Traps formation, and
global
epidemics of emergent/mutant micro-organisms - will, either
individually or
in concert, destroy human civilization, at some unknown date in
the future,
or, at worst, even the entire species.
This being so, can we predict or further elucidate these threats,
mitigate
them, or even with imagination and foresight, turn them to our
advantage?
I think we can take it as read that prevention of volcanism, or
the outbreak
of mutant micro-organisms, is at present, and for the conceivable
future,
beyond our reach, since we do not have access to the magma source
of
volcanic activity, nor the DNA of viruses or bacteria in the
field. We can
be aware of the risk of epidemics of emerging viruses in
our economic and
social activities ; the possibility of disturbing the
ecology of possible
vectors in new land usage and settlement can be factored into
risk
assessments - but this is a long way short of prevention!
Surprisingly, however, accurate assessment of the risk from Near
Earth
Objects is not only eminently possible at reasonable cost, but
can actually
yield invaluable economic results for the future.
The Spaceguard Foundation has shown that a network of six
dedicated 2 metres
telescopes can be had for $30 millions per year, which
would detect 90 % of
potential asteroid impactors over a decade, and nearly 100% of
any over 2
kilometres - the biggest of the threats. A 1 kilometre
impactor, on present
knowledge, is expected, statistically, every 100,000 years or so,
and can be
expected to kill at least 1.5 billion people at a cost of
one trillion
dollars. Insurance industry risk assessments now put the risk to
any
individual being killed in a global impact event as twice
that of being
killed in an aeroplane crash, and 10,000 times that of dying of
human
variant BSE (on whose prevention the UK has already spent over
£3 ($5)
billion in four years!), Actuarially, the cost of
doing NOTHING is
calculated as £123 ($200) millions per year, or £800,000 per
life
($1,350,000), every year, for 100,000 years. If my bullet theory
with its
volcanic/epidemic "extras" is correct, this figure
could easily be
quadrupled.
In considering any action against a discovered impactor, detailed
in-situ
structural knowledge will be needed. With the emergence of low
cost
interplanetary missions, and the advent of private
entrepreneurship into the
space arena, an annual mission to one asteroid or comet can be
launched and
operated for $50 million dollars.
Thus the essential reconnaisance for preparing an effective
response to the
NEO threat - and, very possibly, the volcanic Traps and global
pandemic
threats insofar as these can be linked - can be achieved for less
than $100
millions per year, and, with advances foreseen in space
technology over the
next decade, considerably less.
Prevention
At the present time, the only immediately apparent countermeasure
is a
massive nuclear warhead detonated in, on, or near a detected
impactor. There
are problems here. A long lead time is needed for an effective
deflection,
since even a 100 megatons bomb ( requiring a Saturn 5 class
rocket) could
only alter a 1 kilometre object's velocity by a few centimetres
per second.
Given decades of warning, this could suffice in some cases.
However, new
long period comets, such as Hale-Bopp and Hyakutake, only give ,
at best a
few months' warning. The same applies to some classes of
asteroids, eg the
Atens, which orbit, for the most part, between Earth's orbit and
the Sun .
Further, a nuclear explosion could easily split an impactor into
two or
three deadly fragments, "converting a cannon ball into a
cluster bomb", as
the saying goes.
Evidence from Asteroid Mathilde, visited by the Eros probe in
1997, suggests
that even a massive detonation will not destroy some asteroids
easily or
predictably.
Future less drastic but safer measures, have been proposed. These
include -
1/ Laser vapourization of carefully selected areas on a target's
surface, so
as to induce a geyser or plume which would change its path by a
rocket
effect; this happens naturally in some comets as they approach
the Sun and
lose surface volatiles.
2/ Deflection by planting a huge but very thin mylar film over
the
approaching surface, to act as a solar sail
3/ Emplanting a mass driver catapult on an impactor's surface,
which would
mine the body, convert the proceeds into pellets, and create a
rocket effect
by ejecting these pellets using solar- or nuclear- powered linear
acceleration
4/ Mining one surface of the asteroid - if comparatively small -
into an
aerodynamic shape known as an anhedral or Waverider, so that it
would skip
out of the Earth's atmosphere rather than impact.
These methods are not exhaustive, nor panaceas. They would only
apply in
some cases, and would do nothing against a major 5-10 kilometres
class
"dinosaur killer", whether new comet or asteroid.
Irrespective of whether
geologists accept that an impactor killed the dinosaurs, one fact
is beyond
dispute- it would certainly kill us!
They have, however, one feature in common; all of them require
the presence
of Man, or at any rate his technology, in Space. Lasers , because
of the
Earth's atmosphere, would have to be based on the Moon, or an
asteroid to
achieve range and collimation, while the other techniques self
evidently
predicate local engineering!
An Earthbound Humanity has no options, or at best only the
nuclear, option
in the face of this threat; with access to Space, other presently
fanciful
options have a chance of development
We have thus arrived at a point where a truly radical conclusion
can be
drawn; the survival of human civilization can ONLY be assured by
the use of
space exploration, development, and settlement. Just as our
marine
ancestors, for obscure reasons, embarked on the settlement of dry
land, so,
too, our civilization must embark on the colonization of space.
Since this
will take a very long time, and the timing of a fatal
impact is not known,
the only insurance policy which makes sense is investment in
Space
technology while our culture is still up to the job.
It has been shown (O'Neill, Space Studies Institute, and others)
that, if
the formidable problems of building a spacefaring civilization
using solar
energy and the self same NEOs and Moon we have been discussing
can be
solved, humanity can be supported in greater wealth and profusion
than can
be accomplished on Earth.
It has been proposed by anthropologists that the Agricultural
Revolution was
not some great act of visionary progress, but a measure of
desperation
caused by the extinction, by humans, of the Ice Age fauna which
our
ancestors hunted. Be that as it may, agriculture enabled the
growth of
population, and that diversity of skills which we call
urbanization and
civilization. Indeed, the citizens of Ur reached capabilities
which would
have been qualitatively beyond the imaginations of the hunters of
the
Lascaux Caves! Just so, our marine ancestors could not
conceivably have
developed fire, architecture, astronomy or flight had they not
undertaken
the risky task of settling a hostile dry world.
It is thus at least probable that the evolutionary task of
becoming
creatures of the Universe, freed from the hazards of one planet,
will alter
us in ways beyond the imagination of our contemporary
bean-counting culture!
It will cost lives and treasure, and be enormously difficult -
but the prize
is nothing less than a Universe open to trillions.
The threat from NEO impacts, then, is unique above all other
hazards facing
civilization- it is inevitable, fatal, predictable and avoidable
- true;
but, much more than these things, it can be turned to our profit
and the
enhancement of Mind and Life. It shows clearly the true role of
Mindful
humanity in a Cosmos often deemed to be purposeless - the
dispersal and
development of Life and Mind on the largest possible canvas.
This Idea of Evolutionary Cosmic Destiny, is revolutionary in its
implications and evolutionary in its scope - but is it ethical in
today's
world?
We have seen that, nuclear weapons apart, we are powerless
against the NEO
threat without space development, and, since we are to do this,
we can turn
it to our benefit. It can be accomplished without threat to any
known life
forms in this solar system. Neither the Moon, Mars or asteroids
and comets
have been shown to carry any lifeforms higher than a microbe- and
these are
pretty doubtful by now.
The alternative, as we have seen, is the inevitable destruction
of
civilization, perhaps humanity, with incalculable misery for all
concerned.
To do nothing in the face of a possible alternative is itself a
choice and a
decision - and amounts to suicide - since deliberately not to
prevent a
preventable disaster, or to mitigate it, is an act of suicide.
Moreover,
since billions of people are at risk, possibly the whole Race, we
are
talking of something which has no name - Genocide is the
deliberate murder
of a whole people; beyond that is the murder of a whole species,
for which a
term more pejorative than genocide has yet to be coined!
To commit, by inaction, the descendants of a whole species to
extermination
is an act of destruction which cannot be defended. The excuse,
that it is
Nature's way, leaves out the fact that human intelligence,
science, and
technology are of themselves natural outgrowths, and are
Nature's way of extending and developing Life and Mind . It is
possible,
going beyond strict science for a moment, to see the development
of Mind as
Nature's - some would say Providence's - response to the threat
of repeated
mass extinction events. Such a view restores a sense of purpose
to a
Humanity bereft of meaning these past two centuries and more, and
paves the
way to a more fulfilling future in the new Millennium. We thus
have to
regard opposition to space exploration, development, and
colonization as a
kind of vicarious suicide leading on to genocide and worse.
The last century has seen an ideological conflict between Left
and Right
which at times has brought us to the brink of annihilation. The
coming
century will see, increasingly vividly, a no less important
ideological
struggle, between Up and Down.
The lives of countless billions depends on the victory of the
"Ups"!
1David Brez Carlisle- Dinosaurs, Diamonds, and Things from Outer
Space
2 Faith Vilas, The Planet Mercury, The New Solar System, Beatty,
Collins and
Chaikin, 4th Edition
Dr Michael Martin-Smith, BSc, MRCGP, FBIS, Jesmond, Salisbury St,
HULL HU5
3EU England
President of Space Age Associates,
http://www.astronist.demon.co.uk/index.html
Spaceguard -UK http://dspace.dial.pipex.com/home/terrace/fr77/
Author, of the book "Man Medicine and Space",
available by Print on Demand
from www.iuniverse.com or
Barnes and Noble booksellers at www.bn.com