PLEASE NOTE:
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CCNet SPECIAL: THE "OUT OF THIS WORLD" THREAT
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From Sourcerunner.com, July 2001
www.sourcerunner.com/content/lineno33/investigative/neo_introduction.htm
By Matt Harrington
It sounds like something that belongs in Hollywood. After all,
the idea
scored two summer blockbusters in Armageddon and Deep Impact.
Most
Americans, and probably most people throughout the world, have
the
mentality of "Oh, that will never happen..."
Unfortunately, by the rules of science and statistics, it will
happen.
It is no longer a question of if, but when.
It is the threat of an asteroid striking an impact into the
Earth's
surface.
This threat is so real that as this investigative report is
processed,
an asteroid could be blazing through space on a collision course
with
Earth. Even worse is the possibility that one capable of nearly
wiping
out humanity could have just entered Earth's atmosphere, and we
would
not have known about it.
It is inherent that the above analogy is, of course, a theory
that,
while it may be true and proven, may be composed a millennium or
two
premature. An asteroid of any notable size may not strike the
planet
again for 100 million years. However, there is also the
possibility that
I will win the lottery, wake up next to Pamela Anderson Lee, and
be
named Time's "Man of the Year" all in the same day.
Some things are
certainly possible, but not likely to say the least.
However, efforts to counter this threat of biblical proportions
are
nowhere near where they need to be.
To date, scientists estimate that there are roughly 1,000 of
these Near
Earth Objects (NEO) bigger than 1km in size, and 1,000,000 or so
larger
than 50 m in diameter (the threshold for breaking through the
Earth's
atmosphere).
Despite the importance of the NEO search, fewer than 100 people
are
directly involved with the search at this time. This is a number
that
must change.
Out of the groups involved in the search, and the most
productive, is
the LINEAR search program. Headed by MIT's Lincoln Lab and based
in New
Mexico with US Air Force and NASA support, LINEAR operates to two
telescopes and has dominated NEO search efforts over the past few
years.
Other search groups include: NASA and the U.S Air Force's
co-sponsored
NEAT search program in Hawaii; the University of Arizona's Space
Watch
Survey; the LONEOS survey at Lowell Observatory in Flagstaff,
Arizona;
and the Catalina Sky Survey in Tucson Arizona, both of which are
supported by NASA. Additionally, there are other International
search
programs, along with contributions from amateur astronomers.
In 1998, the U.S federal government analyzed the NEO threat with
"Asteroids: Perils and Opportunities," a hearing before
the
congressional Subcommittee on Space and Aeronautics.
Congressman and Chairman Dana Rohrabacher scolded NASA at the
hearing
for not "walking the talk," by funding the NEO search
program at
suggested levels.
NASA countered by stating that they had developed a rich program
of
research on asteroids and comets which will provide essential
information if the nation were ever to divert an asteroid. Dr.
Carl
Pilcher, of the University of Arizona, stated that their Space
Science
Strategic Plan includes logging 90% of the NEOs with diameters
larger
than 1 km within 5-6 years and that NASA has put into place a
program
that duplicates this same duty. He also stated that the budget
has been
doubled to $3 million and NASA will maintain at least this level
of
funding in the future.
Additionally, NASA is providing approximately $1 billion,
including the
recent and heavily publicized NEAR Shoemaker mission, over the
next
decade in asteroid/comet missions. These missions will study the
make-up
of both asteroids and comets, which scientists have argued will
help in
planning possible deflection strategies.
Despite the importance of the NEO search, fewer than 100 people
are
directly involved with the search at this time.
It is these deflection strategies that have garnered interest
ranging
from PhD's to high school science classes. Romanticized somewhat
by
Hollywood, these strategies would require planning and accuracy
on
levels never seen before. They certainly couldn't be managed in a
year
or two, let alone 18 days, as Armageddon would have you believe.
Realistically, after a decade so or planning, one would see a
robotic
mission of some sort go into action. This, however, is where the
debate
begins.
Everything from attaching solar sails to the surface of the
asteroid to
nuclear detonation has been theorized. There is no
"right" answer on how
to solve a potential deflection scenario, but as mentioned above,
the
precision of the plan would have to be perfect. The slightest
miscalculation could lead to turning one giant asteroid into
several
smaller ones, which could create a larger global catastrophe.
Presently, there is no such plan in place, and if an asteroid or
comet
had a scheduled rendezvous with the earth, there is nothing we
could do,
regrettably.
Depending on the size of the object, a strike to the earth's
surface
would potentially cripple, and possibly bring an end to
civilization as
we know it. A "nuclear winter" of sorts would develop,
as dust would
block incoming sunlight, and would in turn drastically reduce
temperatures, ruin crops, plants, etc. If the object were to slam
into
one of earth's oceans, a tidal wave of unimaginable proportions
would
develop, traveling faster than the speed of sound, and
obliterating
everything in its path.
The sheer horror of the end of the world also brings up the point
of the
public's "right to know."
In March of 1998, this very dilemma was brought to the forefront
of the
world, as for a very brief period astronomers thought they had
discovered a doomsday asteroid. Headlines of "the end of the
world" were
seen on newspapers across the globe.
However, after more data was collected, scientists reversed their
previous statement and said there would be no chance that the
asteroid,
known as 1997 XF11, would come any closer than 600,000 miles from
Earth.
Most people would agree we have a right to know if we are going
to die,
but along with it is the dilemma of maintaining some sort of
global
stability in order to avoid complete chaos. This is important, as
international cooperation and focus would be vital in the success
of a
deflection mission of any kind.
This introduction is just the tip of the iceberg, as this
investigation
will show.
I recently sat down with NEO expert Dr. Benny Peiser to gain a
better
scientific explanation of this threat, and to see what is keeping
it
from getting the attention and funding that it so desperately
needs...
For Part 2 of this investigative report, I got the scoop on this
threat
from NEO expert, Dr. Benny Peiser of Liverpool John Moores
University in
the U.K., and moderator of the Internet newsletter, CCNet.
Here's this one-on-one interview...
www.sourcerunner.com/content/lineno33/investigative/neo_interview.htm
1. You moderate CCNet, a very popular NEO newsletter. What do you
hope
CCNet will accomplish, and what has it accomplished already?
Since its start in 1997, CCNet has attracted more than 1000
subscribers, half of whom are astronomers as well as planetary
and Earth
scientists. As a scholarly network, it has become the most
reliable news
outlet and discussion forum regarding the potential threat we
face due
to the impact of cosmic objects. That's why more than 200 science
journalists from around the globe are also members of CCNet. As
the
founder and moderator of CCNet, it is my aim to provide accurate
and
reliable information that is based on hard evidence, rational
thinking
and not on exaggeration and hype. I also hope that the
responsible and
dispassionate way CCNet is handling a potentially catastrophic
issue
will serve as a positive example how to deal, in a rational way,
with
other environmental threats.
2. How can a SOURCERUNNER reader subscribe to the CCNet
Newsletter?
That's easy. They only need to contact the CCNet moderator
(that's me)
at Liverpool John Moores University <b.j.peiser@livjm.ac.uk>
- and
they'll be subscribed.
3. Despite increased efforts by the scientific community, the
public at
large is still very unaware of this threat. What can be done to
improve
public understanding of the NEO threat?
Due to the ongoing research by astronomers and the reporting in
the
media, I believe that the public is only too aware of the general
impact
hazard. The best way to improve the public understanding of the
NEO
threat is to present our scientific findings in a clear and
matter-of-fact manner. We have to strike a balance between
presenting a
threat that has the potential of being extremely severe, and our
realization that the probability of a massive catastrophe is
extremely
remote in the near future.
4. To almost contradict the last question, should the public be
more
informed about the situation? Should it be left to the government
and
scientific community, as "panic mode" is always a
possible negative
side-effect to a more informed public.
It is not so much a question of "more" than a question
of being better
informed. The public has every right to get accurate information
that is
well balanced. Too often, we have been using the wrong language.
But I
should add in our defense that the NEO community has been going
through
a very significant learning process. To its credit, many of us
have
learned our lessons from past mistakes.
5. Has the Astronomical community taken any kind of uniformed
stance on
the public's "right to know" about a possible NEO
impact?
The International Astronomical Union has drawn up guidelines how
to
announce a possible impact threat. Unfortunately, these
guidelines are
flawed and have already caused a number of false alarms. The main
problem has been that potential impact threats were announced
prematurely instead of waiting for more observational data.
Embarrassingly, these false alarms had to be retracted once new
data
became available. I and others have called upon the IAU to change
these
guidelines so that the NEO community will be protected from
accusations
of "crying wolf". Instead of rushed announcements and
false alarms, it
would be much wiser to make the data of such potentially
hazardous
objects available on the Internet. In almost all of these cases,
more
observational information about newly discovered asteroids will
eliminate them as a potential threat.
6. Is the NEO search in better hands with the government or
private
sector? Is a joint effort better?
I am all in favor of increased private involvement in space
exploration
(including NEO searches and NEO exploration/exploitation).
7. In regards to NEO exploitation, how far away are we from
mining
asteroids for minerals, etc.?
One or two generations for first experimentation - perhaps three
or four
generations for space industrialisation. As far as I see it, it
is
crucial to convey the massage of the enormous benefits the
exploitation
of asteroids and comets has for future space colonization. These
objects
will provide essential resources necessary for space industry and
space
exploration. My guess is that we will have solved the impact
hazard
problem in the next 100 to 200 years, that is if we are lucky
enough not
to be hammered by then.
8. The SpaceGuard Survey is currently hoping to find 90% of 1km
or
larger NEOs before the end of the decade. Why 90%? Why not 100%?
The Americans are very pragmatic people. They don't like aims
that may
not be achievable. Given NASA's limited budget for NEO searches,
they
simply developed a 10-year plan that was cheap and looked
effective.
Many people, however, doubt whether NASA will be able to achieve
even
this rather modest target in the next 5 years or so.
9. What about NEOs smaller than 1km? Is there a search underway
to track
these objects as well?
NEO researchers in the UK, including myself, have argued for many
years
that NASA's obsession with the largest objects (1km+)
underestimates the
more likely threat from smaller NEOs. As a result of our efforts
and
arguments, the UK Task Force on NEOs has acknowledged this
particular
issue and has recommended that specific search efforts should be
undertaken to find those objects smaller than 1km. Obviously, the
likelihood of being hit by such objects is far higher.
10. Hypothetical situation: Let's say a NEO about 3km in size is
discovered. It is projected to strike the earth in 2010. What can
be
done to deflect, or destroy it?
We might be able to do something about it if we had 10 years time
for
preparation. Technological progress is evolving at such explosive
speed,
that an international effort might be able to avert a global
disaster.
On the other hand, we simply lack experimental experience so far.
11. There is a fury of missions currently underway to study
asteroids
and comets. Could you comment on some of these missions, and how
they'll
directly help in NEO deflection?
In order to succeed with NEO deflections, we need to know the
physical
nature and composition of asteroids and comets. The current
asteroid and
comet missions have primarily this particular research focus. The
Deep
Impact mission furthermore will actually attempt to impact a
comet to
assess the reaction of a space object being punctuated. These are
vital
space missions which we need to gain a better understanding of
the
possible methods for planetary defense.
12. Do we have the capability to track NEO impacts on the Moon,
or do we
just have to be "lucky" to see a new one?
Given the growing number of amateur astronomers and the
increasing
sophistication of telescope technologies, it is becoming fairly
easy
nowadays to observe lunar impacts. In fact, lunar impacts were
observed
(and actually video-taped) during the 1999 Leonid Meteor shower.
The
astronomical community would certainly not miss a large-scale
impact.
13. Is it more favorable for our survival for a NEO to strike
over land
or water?
That really depends on the location of impact. Generally
speaking,
impact experts are much more worried about moderate to large
ocean
impacts because the tsunami triggered would cause havoc around
the
ocean's coast lines (many of which are densely populated).
14. Although the science is laughable in some situations, do you
feel
movies like Armageddon and Deep Impact do some good in promoting
this
threat?
Despite artistic and scientific criticism directed against both
movies,
they have helped public understanding of the threat more than all
our
efforts taken together. What is more, they have conveyed the most
important message, i.e. that humankind can actually intervene
into the
course of nature and prevent a repetition of cosmic catastrophe.
That's
Hollywood at its best! It goes without saying that the usual
suspects,
i.e. the doom merchants and eternal pessimist hated both movies.
15. There are several independent groups that monitor the NEO
threat
such as the Near Earth Network, and Interplanetary Protection
Alliance
(IPPA). For small organizations like these to become more
effective, do
you think more cooperation, and perhaps unification is the key?
There is already a great level of co-operation among the
international
NEO communities, both on the professional and amateur level, that
is
much better developed than for most other issues of global
concern.
Despite many heated debates and controversies, there is a very
positive
attitude towards everyone involved in this international effort.
I guess
this positive approach is a reflection of the enormity of the
challenge
we face.
16. An effort is underway to build a state-of-the-art 8-meter
telescope
exclusively for NEO observations. Is this a realistic option, and
what
would be the best option for funding such a large project?
As far as I know this is still a draft proposal.
17. In your opinion, should NASA be doing more to combat this
threat?
What about the other space agencies throughout the world?
For the last 20 years or so, NASA and the U.S. have been doing
most of
the work. That's why I am so appreciative of their efforts,
regardless
of minor quibbles. I hope that the European Space Agency will
soon start
to contribute in a significant way, without simply duplicating
NASA's
search strategy.
18. What deflection strategy do you believe would be the best
approach to stopping a NEO?
Currently, the only realistic option we've got is the use of
nuclear devises for the deflection of an Earth-approaching object
large
enough to pose a significant threat to civilization.
19. What's the largest size NEO that could hit the earth
tomorrow, and
civilization would still be able to survive? What would
conditions be
like after the impact?
Given that Homo sapiens has been around for 5 million years, it
is clear
that we have survived quite a number of large-scale impacts
during that
period. Life - and human life in particular - is much more
resilient
than many think. Yet while we, as a species, would be able to
survive
the impact of objects up to 2 or 3 km in diameter, it would be
too
depressing to consider being bombed back into the Stone Age.
There is
little consolation in this thought.
20. What can the average citizen do to help with the NEO search?
Anything?
The average citizen can help best by becoming more interested and
involved in the whole issue of space exploration. By becoming
more
scientifically literate, people can become directly involved,
either by
making their own observations as an amateur astronomer, or by
lobbying
their representatives on behalf of planetary protection.
21. Are you convinced that it was indeed an asteroid or comet
that led
to the extinction of the dinosaurs. If so, do you think it was an
asteroid or comet?
The hard evidence for an impact (i.e. impact crater, iridium
layer at
the K/T boundary) is so strong that this hypothesis is widely
accepted.
22. Another hypothetical situation: We spot a NEO that is
predicted to
come "too close for comfort" near Earth's orbit. Would
you be in favor
of a mission to alter the NEO's orbit, or would you rely on
predictions
that it will not hit Earth?
Given that these objects follow the laws of gravitation, we can
make
extremely reliable calculations of their orbits. If we know that
on
object will miss the Earth, it simply means: it will miss. There
is no
need for intervention in any such case.
23. What is your opinion of the scientists rushing to release
information that asteroid 1997 XF11 was due to impact Earth?
1997 XF11 was the first major impact scare. While the scientific
information given to the public was accurate, the language used
was
unfortunate. The NEO community has learned its lesson from this
and some
other, very similar asteroid scares that were unnecessary.
Ironically,
we have actually benefited quite significantly from the worldwide
publicity of these false alarms. But there is always the danger
of a
backlash. That's why the NEO community is considering changes to
the
procedures of announcing the discovery of potentially hazardous
objects.
24. Do you feel NASA Administrator Dan Goldin has been a good
ally for
the NEO search?
I'm not aware that Dan Goldin has been much involved regarding
the NEO
issue.
25. Any last thoughts?
We have become aware that life and civilisation on this small
planet is
vulnerable to cosmic dangers. The NEO community is at the
forefront of a
new discussion about humankind's place in space. As a result of
our
scientific development, for the first time in history we can
provide
humankind with the realistic hope of protecting Earth and
guarding life.
It is one of my main aims to turn the NEO threat into an issue
for
raising the hope in technological progress and responsible
intervention
into the course of nature.
(In Part 3 of this investigative report, we will take a closer
look at
one of these independent NEO organizations, the Near Earth
Network, and
their efforts to help combat the NEO threat.)
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