PLEASE NOTE:
*
CCNet ESSAY, 5 October 2000
PEEKING THROUGH CRYSTAL BALLS,
OR WHY WE SHOUDN'T GAMBLE ON THE IMPACT HAZARD
By Bob Kobres <bkobres@uga.edu>
"In my opinion, we are not
adequately addressing even the front
end of this situation until we have
placed detectors where it
doesn't matter whether the weather is
fine or foul. We can, in the
clear light of Space, find, catalog, and
keep track of all those
little bits and pieces that, while not
globally threatening, would
not be welcomed into anyone's
neighborhood!"
-- Bob
Kobres, 5 October 2000
Hey, I want one of those crystal balls that some of you guys must
be
using!
From: http://abob.libs.uga.edu/bobk/ccc/cc100200.html
[. . .]
The first concern is regarding the usage of nuclear power to
mitigate an
impactor. Although the report focuses on the nuclear bomb as one
of many
mitigation methods, it is mentioned explicitly. Some military
people use
the NEA problem to maintain the nuclear bomb. Yet, it is more
dangerous
to keep it than to have a NEA collision in the near future. If we
would
determine all the orbits of hazardous NEA, we could determine
their
collision time well in advance and could mitigate an threat by
some
methods except the nuclear bomb. In any case, it is the most
important
aspect of NEO resesarch to detect all the hazardous NEA since
otherwise
we cannot make any types of mitigation.
[. . .]
Syuzo Isobe
~~~~~~~~~~~~~~~~~~~~~~~~
That it is more dangerous to retain the option of using nuclear
devices
than to have a NEA collision in the near future is an assertion
with
very little, if any, fact to back it up.
This subject has come up before:
From: http://abob.libs.uga.edu/bobk/ccc/cc062598.html
Nuclear reaimament is what I called the potential to convert
nuclear
weapon technology to the task of Earth-defense. Let's face it,
the
genie is out of the bottle. See: http://abob.libs.uga.edu/bobk/1908.html
While there is no way to ensure that this knowledge will not
again be
used to destroy life and property there are ways to make it less
likely
for that to happen. Rather than rehash the steps that could be
taken,
I'll point the reader to earlier documents that express some
still
pertinent ideas:
http://abob.libs.uga.edu/bobk/nucreaim.html
http://abob.libs.uga.edu/bobk/rma.html
I'm no advocate of large-scale Earth-based nuclear use. All we've
managed to do with nuclear energy technology is boil water with a
vengeance, creating a good deal of waste heat plus nuclear waste
storage problems. With nuclear weapons we've actually blown
adversaries
to smithereens and threatened to do so again, ultimately leading
to
various strategic plans of MAD (suicidal vengeance). In other
words the
nuclear-power-genie is a beast in the biosphere-better to banish
what
we've made to the Moon! By verifiably removing weapon grade
nuclear
material from Earth, in conjunction with international
cooperative Space
development aimed at reducing the need of high grade energy
within the
biosphere, we can greatly reduce the potential for conditions
that might
cause a reactionary mess on our planet.
In particular for Mr. Isobe (JAPANESE OBJECTIONS TO THE USE OF
NUCLEAR
DEVICES IN PLANETARY DEFENSE, CCNet 6/22/98), I suggest that he
consider how much Japan could benefit from becoming a pioneer in
developing solar-power-satellite technology. This also includes
ocean
based 'refineries' of such concentrated sun-energy, which could
supply
our civilization with hydrogen as a non-polluting portable fuel
as well
as increasing the supply of potable water.
As I've said many times-YES-we can mess ourselves up with nuclear
technology, BUT-we don't have to. An impact, however, WILL get us
unless we learn how to avoid this otherwise inevitable natural
phenomenon.
Ultimately it is the general regard we have for one another,
coupled
with the dominant vision of our future, that will determine
whether we
continue to advance through knowledge or fall back to a state of
fear
and superstition.
A dozen years ago Joseph V. Smith, Louis Block Professor of
Physical
Sciences at the University of Chicago, in his article, THE
DEFENCE OF
THE EARTH, which appeared in the British Journal NEW SCIENTIST
(17
April 1986), stated the following:
"Although we have known about the dangers of nuclear war for
40 years,
they continue to increase as technology develops, driven by
divisive
bickering over social, political, nationalistic and religious
matters.
"How are my proposals related to the dangers of war,
especially the use
of nuclear weapons? At the simplest level, huge expenditure on
nuclear
and other weapons eats up technical resources that we could
better use
elsewhere. We could apply some of these resources to the
programmes I
propose here, some for the enrichment of education, and the rest
for a
host of other needs including exchange programmes to promote
interactions between people with different histories and
philosophies.
The fewer the scientists and engineers working on weapons, the
slower
the pace of development, and the better the chance that
diplomatic
negotiations can achieve success. In addition, if fewer people
worked in
weapons factories, and more on building instruments to study
asteroids,
comets, volcanoes and earthquakes, conventional and nuclear wars
might
also cause less damage. At a deeper level, there is the hope that
a
worldwide collaboration of scientists and engineers, working
together in
groups organised in a diplomatic consensus, will set an example
of
harmony that will lead us away from present disputes. Instead of
acting
like primitive tribes hunting heads, we might develop a feeling
that we
belong to one race irrespective of colour, religion and
historical
grouping.
"The genuine dangers of nuclear war have overshadowed the
threat to
humankind from natural hazards--hazards that few people fully
recognise. Such dangers have become obvious over the past 20
years to
geologists and astronomers.
"We can now propose sensible methods to prevent or mitigate
them. Given
worldwide cooperation over the next century, we could kill two
birds
with one stone if we reduced expenditure on weapons, and engaged
the
scientists, engineers and manufacturers in new programmes to
defend
people from natural hazards. All scientific and engineering
developments have the capacity for good or evil. Let us choose
Dr.
Jekyll over Mr. Hyde."
Choice is the real crux of the matter. Nuclear weapons will be
around
as long as people fear another group might attempt to gain
control of
them or their resources. We can expand our collective resource
base and
cause covetousness to diminish by electing to convert PHOs to
BROs
(benign resource objects). We can actively build trust between
disparate cultures by choosing to work together to accomplish
this
necessary for long-term-survival goal. We could also just hope
for the
best and decide to talk about doing something for a couple of
more
decades. Remember, the only certainty is change--better to steer
toward
a positive ideal than drift into chaos. In my view, Earth-defense
is not
just about comets and asteroids, it is rather more about our
attitude
toward our future.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
From:
http://abob.libs.uga.edu/bobk/ccc/cc100400.html
[. . .]
In short, it is not the fact that an asteroid has missed Earth
that
should focus the public's minds, but whether such an asteroid
could pose
a potential threat in the future. The more we become aware of the
normality of "near-misses," the more the interested
public need to
understand and appreciate how reliable orbital calculations are
that can
(and in almost all cases) will eliminate any individual NEO
threat for
at least the next 100 years or so.
[. . .]
Benny J Peiser
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
If we KNOW that a PHO harbors no volatile elements then we can be
pretty
confident of orbital calculations. Without a more
aggressive
Space-based detection system I do not think we can be certain
that all
found PHOs are incapable of farting around with their
orbits. Comet
Encke was apparently a dark object for some time but as it
regained its
glow it began to slow, losing about two days of orbital period
between
1789 and 1838 (Whipple, 1985, The Mystery of Comets, page
92).
This too has come up before:
From: http://abob.libs.uga.edu/bobk/ccc/ce062299.html
So back to this fixation on quantifying our chances of being
zapped by
this or that type or size object--What difference does it make?
Unless
we are prepared or are fortunate enough to identify the next due
event
distant enough in time for us to get ready to deflect it, we're
eventually going to get popped regardless of our calculations and
observations. I also question the belief that comets pose less
risk
than our local swarm of dark objects. For one thing we do not yet
know
what fraction of these short period objects might be stealth
comets and
so still have sufficient volatile material to covertly fart
around with
their orbit near perihelion. As for active comets--by Jove we
could get
in trouble quickly.
Our closest recognized brush with an out-gassing object occurred
in
1770 when a comet discovered on June 14 of that year, by Charles
Messier, came within 0.015 AU of Earth around two and a half
weeks
later--the evening of July 1. On that night the comet's coma
appeared
to be about five times the apparent diameter of the Moon! The
most
interesting thing about this happening, from an Earth defense
viewpoint, is the cosmic gymnastics that comet 1770 I Lexell
underwent
between 1767, when Jove lobbed it into our neck-of-the-solar
system and
1779, when after only one other plunge near the Sun in 1776 the
mighty
Jupiter tossed it to who knows where. In other words, prior to
1767
this comet reached perihelion at around 3 AU and could not affect
Life
on Earth, however, after getting a bit too cozy with Jove around
the
middle of that year it became a potential hazard to Earthlings
with a
lead time of just three years! How often do these rather
flamboyant
members of our solar system get tossed around like this? Do such
orbital contortions generally leave the object discrete or are
the
victims of Jupiter's pull more often scattered into a cosmic
hail-storm
of sorts, as we witnessed with Shoemaker-Levy 9? Did Earth
collect a
bit more dust than typical due to this close encounter (177 Earth
diameters) with 1770 I Lexell so soon after that comet was
wrenched
from its former orbit and what size object was this--kilometers
across,
tens of kilometers, hundreds? Don Yeomans, in his COMETS (1991,
page
162) reports that eight comets (inclusive of Lexell) came within
2500
Earth radii during the eighteenth century--Did dust from these
visits
contribute to the factors that produced such variable and often
unseasonably cold weather in the 1700s?
<http://abob.libs.uga.edu/bobk/yamacuta.html>
Perhaps I'm wrong, but I don't think we have a reliable
observational-
base long enough to accurately answer such questions.
I suggest that our most prudent course of action with regard to
PHOs is
to adopt the policy that has brought Life to its present
situation on
Earth: Mount and probe; mount and probe--this is how Life learns
and
spreads. A wait and see approach to this threat is a gamble that
could
prove fatal--Why take such risk when we do have the tools to more
aggressively address the situation? It's not going to break us or
take
food from the mouths of starving children; it should rather
reduce the
number of Cruise Missiles, B-1s, and similar ilk being produced.
<http://www.worldgame.org/wwwproject/>
To more quickly reach a point were adequate precautions are being
implemented, we need to devote more attention and resources to
revealing the record that remains beneath our feet. I obviously
assume
here that there have been recent significant events that we can
recover
evidence for, but considering the relatively low cost of focused
digging and discerning, it is an aspect of information gathering
that
could well become more convincing to the wait-and-see crowd than
the
bevy of PHOs already identified. Financial support for such
activity
should certainly be added to allotments that have been awarded to
sky
focused fact gathering! Such research would seemingly coordinate
nicely
with climate change investigations and could substantially
broaden
awareness of this issue among more down to earth researchers.
In my opinion, we are not adequately addressing even the front
end of
this situation until we have placed detectors where it doesn't
matter
whether the weather is fine or foul. We can, in the clear light
of
Space, find, catalog, and keep track of all those little bits and
pieces that, while not globally threatening, would not be
welcomed into
anyone's neighborhood!
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In general I believe that it is wisest to acknowledge that we can
but
feebly predict the future. Change is relentless and is what
provides
reality with any structure at all. As we learn to better
gauge our
situation and understand more of how the living world thrives and
survives we may become more adapt at mitigating unhealthy
changes.
We are a highly manipulative and adaptable breed of critter but
our
degree of control over other natural forces is pretty tenuous as
yet
--we do not even control our own behavior well.
The Cult of the Tubeless Tire has grow remarkably fast.
Inflated by
creative people trying to improve our abilities to do new things
with
new knowledge, a myriad of roads to travel loom before us.
Let's not
forget that driving too fast or recklessly could cause that great
god,
Firestone, to come unglued, fall flat, and leave us all in a
ditch. ;^)
Treading as lightly as we can on the rest of nature is as we
learn to
better understand and protect it is most effective way to steer
clear of
extinction for ourselves as well as other living passengers on
this
planet.
Hopeful but tired--(literally)--had to get to work before the
chickens
woke up this morning!
bobk
Bob Kobres
bkobres@uga.edu
http://abob.libs.uga.edu/bobk
706-542-0583
Main Library
University of Georgia
Athens, GA 30602
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