Inside the Boardroom with Alan Bagley - SETI Institute

Explorer
Second Quarter 2005
Volume 2, Number 2
SETI INSTITUTE

Contents
03 Letter from the CEO
03 Science Editor’s Desk
04 Saving the Planet
06 Cracking the Code of Pre-Earthquake Signals
09 Perseids
10 Planetary Defense in Space
12 Reacting to Disaster
14 Cosmic Catastrophe and Armageddon
16 Inside the Boardroom with Alan Bagley
17 Cosmic News
18 Here Comes Andromeda
21 Allen Telescope Array Update
22 The SETI Institute’s New Educational Classes
Explorer
Editor in Chief
Karen Randall
Science Editor
Seth Shostak
Creative Director
Ly Ly
Managing Editor
Jennifer Bugnatto
Assistant Designer
Ngan Truong
Contact us
Annual Fund Manager
Natalie Jackson
SETI Institute
515 North Whisman Road
Mountain View, CA 94043
Telephone: 650.961.6633
FAX: 650.961.7099
www.seti.org
membership@seti.org
Board of Trustees
Greg Papadopoulos
Chairman of the Board, SETI Institute
Executive VP and Chief Technology Officer,
Sun Microsystems
John Billingham
Vice Chairman of the Board, SETI Institute
Former Chief, NASA ARC, SETI Office
Thomas Pierson
Board Secretary, SETI Institute
CEO, Founder, SETI Institute
Alan Bagley
Former General Manager, Hewlett-Packard Co.
Founder, Los Altos Community Foundation
Linda S. Bernardi
Founder, CEO, and President, ConnecTerra, Inc.
Trustee, Institute for Women and Technology
Joel S. Birnbaum
Senior Technical Advisor, Hewlett-Packard Co.
Former Sr. VP of Research and Development,
Hewlett-Packard Co.
Chair, National Research Council Committee on
Improving CyberSecurity Research
Member, National Academy of Engineering
Fellow, Institute of Electrical and
Electronics Engineers, Inc.
Baruch Blumberg
President of the American Philosophical Society
Nobel Laureate, Prize in Medicine
Distinguished Scientist at Fox Chase Cancer Center
Former Director, NASA Astrobiology Institute
Member, National Academy of Sciences
Frank Drake
Chairman Emeritus, SETI Institute
Director, Center for the Study of Life in the Universe,
SETI Institute
Member, National Academy of Sciences
Sandra Faber
Professor, University of California at Santa Cruz
Member, National Academy of Sciences
Member, President’s Advisory Panel,
National Academy of Sciences
Andrew Fraknoi
Chair, Astronomy Department, Foothill College
Director, Project ASTRO
Former Executive Director, Astronomical
Society of the Pacific
Carl Sagan Prize for Science Popularization
John Gertz
Founder and CEO, Zorro Productions
Steven L. Mourning
Executive VP, Kelmoore Investment Co.
Former Chief Development Officer, Palo Alto
Medical Foundation
David Nagel
President and CEO, PalmSource, Inc.
Former Chief Technology Officer, AT&T
Former Member, President’s Information Technology
Advisory Committee
Lewis E. Platt
Former CEO, President, and Chairman,
Hewlett-Packard Co.
Chairman, Boeing Co.
Board member of 7–Eleven and
The Packard Foundation
Member of Advisory Committee on
Trade Policy and Negotiations
Former Chairman of the World Trade Organization
Task Force
David Pratt
CEO, Callidus Software
Former Executive VP and Chief Operating Officer,
Adobe Systems, Inc.
Charles Townes
Professor Emeritus, University of California at
Berkeley
2005 Templeton Prize
Nobel Laureate, Prize in Physics
Member, National Academy of Science
Member, National Academy of Engineering
William J. Welch
Professor of Astronomy, University of California
at Berkeley
Watson and Marilyn Alberts Chair, UC Berkeley
Member, National Academy of Sciences
SETI Institute Explorer

Letter from the CEO
July 2005
Dear SETI Institute supporter,
Previously, we introduced the world of extremophiles and their ability to survive
the most intense of conditions. We now shift our focus to humankind’s key to
survival: foresight.
In this issue of Explorer, we examine a wide range of potential threats to Earth
and consider what we might do to protect ourselves. Preparedness lies in the
willingness to face these threats head on, educating ourselves now before the danger
is imminent.
Catastrophic changes to Earth’s environment 65 million years ago that led to the
extinction of the dinosaurs—often attributed to the impact of a massive asteroid on
Mexico’s Yucatan Peninsula—also allowed for the rise of the mammals, eventually
yielding humankind. Life on Earth is tenacious, always ready to take advantage
of chance circumstances. The concept of 65 million years seems improbable to a
society that prefers the speed of sound to the speed of evolution. As Louis Pasteur
put it, “chance favors the prepared mind.” Preparing now through education and
research is our insurance policy for the future.
With warm regards,
Tom Pierson
Chief Executive Officer
SETI Institute Mission Statement
The mission of the SETI Institute is to explore, understand and explain the origin,
nature and prevalence of life in the universe.
On the Cover
An artist’s rendering of an asteroid heading toward Earth.
Image courtesy Seth Shostak
From the
Science
Editor’s Desk
by Seth Shostak
Two decades ago, I pitched what
I thought was a great story to
the science editor of a national
magazine. I offered to describe
the inevitable death of the universe.
I got an angry rejection, with the complaint
that the idea was both “dystopian
and completely speculative.”
Well, no argument with “dystopian.”
But I took umbrage at “completely speculative.”
Sure, many aspects of our planet’s
future, and for that matter, the fate of the
We can’t reliably predict
societal evolution, or
even our own personal
behavior next month.
But physics is forever.
universe, remain subject to chance (will
Earth be flash-sterilized by a gamma ray
burst) or poorly known (when, exactly, do
all the protons disintegrate).
But predicting the future of the
universe – even foretelling what will happen
a trillion trillion trillion trillion trillion
years from now and more – is not like trying
to guess the stock market. It requires
only a few astronomical observations and
physics.
We can’t reliably predict societal evolution,
or even our own personal behavior
next month. But physics is forever. Ten
millennia from now, folks may not be
greatly attuned to the art and music of
the 19 th century, but they will still expect
their electronic devices to work. And those
devices will be built on the basis of James
Maxwell’s equations from the 1870s.
Science is rewarding for a lot of reasons.
It’s exciting and it’s challenging. Sure, being
a tax consultant helps folks, and it pays
the bills, too. But in the 101 st century, those
tax forms will be archaeological dross, and
not of much relevance. On the other hand,
the discoveries of science will still be hanging
in there. They’ve got legs. After all,
once we’ve uncovered one of nature’s secrets,
her behavior is no longer “completely
speculative.”
Second Quarter 2005 - Celebrating our 20th Anniversary

Astobiology
Education
Artist’s concept of a meteor shower in
prehistoric times.
© David A. Hardy/ www.astroart.org
Saving the Planet
Science Education is Good for Everyone’s Future
by Seth Shostak
It’s a familiar chestnut: “the dinosaurs would be around today if they only had a space
program.” Of course there’s truth in this. If the lubberly lizards that once stomped the
planet had rocket technology, they might have deflected the 5-mile diameter asteroid
that speedily incinerated them and subsequently starved most of what remained.
SETI Institute Explorer

Of course, a space program – while necessary
– wouldn’t have been sufficient to
forestall the dino’s incandescent demise. A
good defense would have required an active
astronomy effort to detect the incoming
rock. Physics was essential as well, for
otherwise how could they calculate the
asteroid’s orbit
This is an all-too-elaborate digression
on a wry joke, but there’s little doubt that
our brains, schooled in science, can insure
us against the sort of cosmic catastrophes
that might afflict us in the next few tens of
billions of years.
For example, imagine the sorts of things
we might do when faced with an impending
ice age. Such an event can begin rather
quickly (in decades), and would be disastrous
for Canada and Europe. But fending
off the Big Chill might not be impossible.
One approach would be to decrease Earth’s
albedo – which is not its lust for other planets,
but the fraction of incoming sunlight
that it reflects back into space. In other
words, we could arrange for our planet to
be less bright. A way of doing this would be
to use a fleet of aircraft to layer the ice fields
of the arctic with coal dust, so they became
warmer in the sun.
As an alternative to this gritty approach,
we might, by the end of this century, be capable
of building very large, orbiting solar
reflectors, aimed earthward to bring a little
more light into our lives. If we increased
the amount of sunlight hitting our planet
by 10% or so, we’d no doubt reverse any
cooling trend.
Another straightforward possibility
would be to bring back Freon, the coolant
that once circulated in our refrigerators and
air conditioners. It’s a great greenhouse gas
(which, of course, is why it was phased out),
so smashing up old fridges, and thereby
boosting the greenhouse effect, could keep
the world from growing cold. You could
also buy an extra SUV, which would do
much the same. Let’s face it: ice ages have
been scraping up the landscape for millions
of years. But with a bit of informed technology,
we can insure that the last ice age
will be, well, the last ice age.
Consider another imminent threat: a reversal
of Earth’s magnetic field. This would
eventually require a re-labeling of your
Boy Scout compass of course, but the real
problem is what happens during the interval,
halfway through the reversal, when our
planet has essentially no field. High energy
particles that zip through space would no
longer be either repelled or guided to the
poles (where they now produce nice auroras
for the entertainment of Eskimos and
Extreme Ultravoilet Imaging Telescope reveals solar flares from the sun.
elk). Instead, they would rain down everywhere,
inflicting cancers on us, and wreaking
similarly distasteful damage on other
life forms.
But – and this is true for many of the
cosmic disasters that offer to ruin your
whole millennium – this reversal would not
happen overnight. There would be years to
prepare. By staying indoors, and perhaps
adding more insulation to the attic, we
could avoid DNA doom for Homo sapiens.
A harder task would be protecting necessary
wildlife, but keep in mind that there
have been many magnetic reversals in the
past, showing that nature, even without our
help, can take care of its own – or at least,
evolve survivors.
Many of the dangers that will confront
your extremely great grandchildren involve
changes in the Sun. The gradual brightening
of Sol’s ignescent face will begin to interfere
with plant life in 100 million years
or so, but this problem, too, could be engineered
away. By that distant date, it should
be a fairly simple matter to erect orbiting
barriers to reduce the solar flux, or possibly
re-formulate our atmosphere to act as a
natural screen.
In a few billion years, the Sun will begin
to die, swelling up like a puffer fish. An
obvious counter move by our descendants
would be to simply decamp to a cooler
neighborhood, either farther out in the solar
system (think: engineered habitats), or
to another star system altogether. Either
would be a grandiose engineering project,
but this event is in a future so remote that it
would be silly to assume that neither could
be done. And in any case, migration would
probably be simpler than trying to “rejuvenate”
the Sun by changing the conditions in
its dying core – a fix that has occasionally
been suggested by those who like to consider
the possibility that someday we will not
only go to the stars, but interfere with their
personal lives.
There’s no doubt that the universe will
present us with difficult, and occasionally
lethal, events. That’s guaranteed to happen.
The dinos, despite their impressive
bulk and Naugahyde skin, ran head-first
into a cosmic catastrophe. Their bones are
now stacked up, labeled, and on display.
They were incapable of averting disaster.
The same could be true of any society
that doesn’t school its populace in science.
Therein lies a lesson.
Dr. Seth Shostak
Senior Astronomer
SETI Institute
Dr. Shostak has written several
hundred popular magazine and
Web articles on various topics in
astronomy, technology, film and
television.
Courtesy of SOHO/Extreme Ultraviolet Imaging Telescope (EIT) consortium.
Second Quarter 2005 - Celebrating our 20th Anniversary

Astrobiology
by Friedemann Freund
Our Earth is a restless planet.
Occasionally – quite often,
in some regions of the world
– the restlessness turns
deadly. Of all natural hazards,
earthquakes are the most feared. They
are feared because they seem to strike so
unpredictably. Yet, for centuries, and even
millennia, people living in seismically active
regions have noted premonitory signals.
The historical records talk of changes of the
water level in wells, of strange weather, of
ground-hugging fog, of unusual behavior
of animals (both domestic and wild) that
seem to feel the approach of a major earthquake.
With the advent of modern science
and technology the list of premonitory signals
has become even longer. Among them
are:
(1) Sporadic emissions of low to ultralowfrequency
electromagnetic radiation
from the ground
(2) Occasional local magnetic field
anomalies reaching a strength of half
a percent of the Earth’s main dipole
field
(3) Changes in the lower atmosphere that
are accompanied by the formation of
haze and a reduction of moisture in
the air
(4) Large patches, often tens to hundreds
of thousands of square kilometers
in size, seen in night-time infrared
satellite images where the land surface
temperature seems to fluctuate rapidly
(5) Passing perturbations in the ionosphere
at 90 - 120 km altitude that affect the
transmission of radio waves
Collapse of Hanshin Expressway in
Japan
National Information Service for Earthquake Engineering,
University of California, Berkeley
Deciphering these signals and learning
how to “read” them has remained a source
of great frustration. Many seismologists
have lost faith that earthquakes would ever
become predictable beyond statistical probabilities
which leave uncertainties of years,
even decades. Some seismologists have
proclaimed categorically that, due to their
SETI Institute Explorer

chaotic nature, earthquakes are fundamentally
unpredictable.
However, given so many well-supported
historical and modern indicators that the
Earth does indeed send out premonitory
signals, we should not be deterred by the
naysayers. Maybe we do not yet understand
deeply enough the nature of earthquakes
and the physics of the signals that the Earth
sends out.
Some ten years ago I became interested
in this challenging topic. My earlier work
had led me to study chemical and physical
processes inside crystals, inside the matrix
of gem-quality minerals, which can shed
light on the origin of life. During this earlier
work I had run across a peculiar reaction,
which nobody seemed to have noted
before, and hardly anybody seemed to care
about. This reaction involves small amounts
of water, H 2
O, which become incorporated
whenever a mineral crystallizes deep in
the Earth’s crust or mantle in a H 2
O-laden
magma or any other high temperature
H 2
O-laden environment. All these minerals,
even those that do not nominally contain
“water” as part of their crystallographic
makeup, structurally dissolve some H 2
O in
the form of hydroxyl, typically Si-OH, and
a major part of it in the form of hydroxyl
pairs, Si-OH HO-Si.
In the mid-1970s, long before I became
interested in either the origin of life or preearthquake
phenomena, I had discovered
that such hydroxyl pairs inside crystals
undergo a very unusual reaction. The two
oxygens and two hydrogens fight over the
electrons that they share, and the hydrogens
win. They each take away one electron
from their oxygens and turn into a hydrogen
molecule, H 2
. The oxygens in turn
pair up to form what chemists call a peroxy
bond: Si-OO-Si.
For years I did not think much of this
discovery, but somehow it followed me and
eventually drew me into the field of geophysics
and the study of the premonitory
signals that the Earth sends out before major
earthquakes.
Electrical Rocks
We normally think of rocks as being good
insulators, i.e., rocks are very poor at conducting
electrical currents. However, in rocks
whose minerals contain peroxy bonds, a time
bomb is ticking. When these rocks are subjected
to stress, the peroxy bonds break and
suddenly mobile electronic charge carriers
appear, so-called defect electrons that live and
travel in the valence band of the constituent
minerals. These charge carriers are also called
Temple collapse caused by the 2004 Mid Niigata Prefecture Earthquake in Japan
positive holes or p-holes for short.
Looking back over the 30 years since
their discovery, I am surprised to note that I
always returned to these strange and elusive
charge carriers. I tried to understand their
nature and to predict their behavior. The
breakthrough came when I realized that
these p-holes could be activated by stress.
This put me squarely on the track to study
earthquake-related phenomena.
Still, it took several years and several
wrong starts until I was able to conceive an
experiment that is amazingly simple and, at
the same time, full of surprises. In Figure
A is shown a 1.2 meter long slab of granite
which, together with my coworkers Dr. Akihiro
Takeuchi and Dr. Bobby Lau, I had fitted
with copper electrodes at both ends to
measure currents and with a capacitor plate
on the top surface to measure potentials. We
inserted one end of the slab into a powerful
press, but insulated it from the pistons.
Then, we started to squeeze. We squeezed
the rock many times and recorded the currents
that started to flow out of both ends.
The experiment showed that the
stressed volume of rock becomes a source
of electronic charge carriers, p-holes and
electrons. Since p-holes and electrons flow
out in opposite directions, something important
must happen at the boundary between
the stressed and unstressed rock. The
boundary allows p-holes to pass but blocks
electrons. It therefore acts like a diode in a
transistor. Obviously the unstressed granite
is capable of conducting p-holes, meaning
that it behaves like a p-type semiconductor.
The electrons can flow out of the stressed
rock volume only if there is an n-type connection
– in our case the copper electrode.
Next we may wonder how long such
currents can flow if we keep the load constant.
We did a similar stress test with
Friedemann Freund
Figure A - 1.2m long granite slab fitted
with two copper electrodes and one noncontact
capacitive sensor set in the press.
Mitsutoshi Yoshimine, Tokyo Metropolitan University
Second Quarter 2005 - Celebrating our 20th Anniversary

gabbro, another igneous rock. Upon keeping
the load constant for 30 minutes, the
two currents flow with barely any loss in
their intensities. Even keeping the load constant
for 12 hours leads to not more than
a 15-20% reduction of the currents. This
shows that, once activated, the p-holes and
electrons in the stressed rock volume have a
very long lifetime.
Use for Earthquake Prediction
How can we apply this new knowledge
to earthquakes and to those hidden processes
that take place deep in the Earth’s
crust before tectonic stresses reach a critical
level where rupture occurs and the ground
starts to shake
Though we stand only at the beginning
of a long road to discoveries yet to come,
we can already project some of our findings
into geophysical reality.
In Figure B, you can see a sketch of a
very simplified model depicting a section
through the Earth’s crust where tectonic
forces begin to act on a large block of strong,
rigid rocks, maybe 100 - 1000 km wide, 20
km thick and 50 - 10 km in the thrust direction.
As stresses build up from the left, they
cause plastic deformation propagating toward
the right. The volume of rocks undergoing
deformation becomes the source of
p-holes and electrons. The p-holes can flow
out horizontally. The electrons can flow out
only if they can connect downward into the
deeper, hotter and, hence, n-type conducting
portions of the lower crust.
In this model we obviously neglect to
take into account the role of water which
fills faults that deeply dissect the Earth’s
crust in all tectonically active regions.
Faults filled with water or brines will introduce
complications, but we already know
from laboratory experiments that water
may short-circuit the p-hole conduction
through the rocks but it does not “kill” it.
Therefore we can cautiously go ahead and
project some of the consequences of the
p-hole activation in rocks that experience
ever-increasing levels of stress.
One of these consequences is that the
p-hole current flowing horizontally through
the crust should couple to the electron current
flowing downward. The coupling is
provided by their respective electric fields.
As a result, both currents can be expected
to fluctuate just like the p-hole and electron
currents did in our laboratory experiments.
Fluctuating currents are a source
of low frequency electromagnetic (EM)
radiation. Thus our model, simple as it may
be, points to the possibility that the often
reported pre-earthquake low frequency
EM emissions arise from ground currents
flowing deep in the Earth’s crust. The
ground currents may be very powerful. For
instance, taking the currents flowing out of
the squeezed end of the granite slab in our
experiment, we may ask what would be the
current flowing out of a cubic kilometer of
granite or gabbro in the crust, all other conditions
being the same. The answer is a surprisingly
large value, somewhere between
100,000 and 1,000,000 amperes. Since huge
volumes of rocks – tens of thousands of
cubic kilometers – come under increasing
stress during the build-up of large earthquakes,
the ground currents could indeed
be enormous. Looking at it from a different
perspective, we can say that, even if most
of the currents generated in the ground
are short-circuited or annihilated by other
factors, those that remain might still reach
impressively large values.
Atmospheric Disturbances
Another result of stress-activated currents
flowing in the ground would be that
some p-holes will reach the surface of the
Earth. They would change the ground
potential over large areas, making it more
positive relative to the surrounding areas.
This would have many consequences, of
which I only want to mention one.
Roughly 90 - 120 km above the Earth’s
surface the ionosphere begins, which is
composed of a highly dynamic plasma of
electrons and ions generated under the
daily assault of extreme ultraviolet radiation
from the Sun, solar wind bombardment,
and cosmic rays. If the land surface
below becomes increasingly positive, this
plasma sheet will react. Maybe the source
for the well-documented pre-earthquake
ionospheric perturbations lies in the
activation of p-holes deep in the Earth’s
crust and the mischief that they play at the
Earth’s surface.
In hindsight it is quite amazing to see
how a line of basic research that, at its outset
three decades ago, seemed to have no
connection whatsoever to the origin of
life and to earthquakes, has become a treasure
trove of insights and discoveries. It is
certainly too early to say that earthquake
prediction is just around the corner. However,
I feel confident that the discovery of
p-holes in rocks and their activation by stress
represents a crucial step toward cracking
the code of the Earth’s multifaceted preearthquake
signals.
Figure B - Simple model of a large, rigid block of the Earth’s crust being pushed from
the left and undergoing increasing levels of stress.
Friedemann Freund
Dr. Friedemann Freund
Physicist, SETI Institute
Dr. Freund is associated with
the SETI Institute, San Jose
State University and NASA’s
Goddard Space Flight Center.
SETI Institute Explorer

Astrobiology
Perseids
© Wally Pacholka/ www.astropics.com
Tune In!
Are We Alone
the SETI Institute’s
Weekly Science
Radio Program
by Peter Jenniskens
For as long as records exist, the
Perseid meteor showers have always
been strong. This summer’s
Perseid shower will be exceptional.
The moon is mostly out of
the way later in the night, and higher-thannormal
activity rates are expected over the
United States.
The Perseid shower’s parent body, comet
109P/Swift-Tuttle, is notable in being a
comparatively huge comet in an orbit that
passes close to Earth’s orbit frequently. It
measures 24 - 31 kilometers in diameter, 2
to 3 times the size of comet Halley, and is so
big that the continuous ejection of water vapor
and dust during its approach to the Sun
does not move the comet much off course.
It has spewed dust for at least 5,000 years
and most likely thirty times longer. It has
built a massive meteoroid stream, most of
which is located just outside of Earth’s orbit.
Earth passes through the outer regions
of that stream in July, and hits the center on
August 12. At that time, the annual Perseid
shower peaks at 80 meteors per hour under
ideal circumstances (no clouds or moon,
dark sky, stars of magnitude +6.5 just visible).
When comet 109P/Swift-Tuttle was
rediscovered in 1992, scientists noticed in
alarm that a delay of 17 days in the next
projected return of the comet in 2126 could
cause it to collide with Earth. That fear dissipated
when the orbit was recomputed
using data from sightings in 188 A.D. and 69
B.C. The more precise orbit has the comet
approach Earth in 2126 to within only 23
million kilometers, but there’s no danger of
us being hit. In September 4479, the comet
will approach Earth even closer, to within
about 6 million kilometers. It will then be
as bright as Jupiter (-2.1 magnitude) in
the sky.
The dust released will spread along the
comet orbit because some dust grains make
wider orbits than others and return later.
When Earth encounters these dust trails,
a meteor storm may be observed. But only
if the very narrow trail is steered smack in
Earth’s path by perturbations of the planets.
Most dust does wander far from the comet,
which is why the best showers are observed
in the years following when the comet returns,
while lesser outbursts occur when
dust further along the comet orbit wanders
into Earth’s path.
The next big shower is not expected until
the next return of the comet. For now,
a nice outburst is projected for August 12,
2005, at 08:18h UT (= 04:18 EDT and 01:18
PDT), when Earth will encounter the dust
ejected in the return of 1479. Rates can go
up four fold to about 240 per hour on top of
the 80 per hour annual activity, for a brief
period of time (approximately 1.2 hours).
In addition, rates may increase again
around 13h UT, when Earth is slated to encounter
the Filament component, rising to
less than 86 per hour on top of normal, annual
activity. That Filament is older dust
presumably in mean-motion resonance
with Jupiter.
Dr. Peter Jenniskens
Astronomer, SETI Institute
Dr. Jenniskens studies meteor
showers in order to understand
the origins of life on Earth.
Listen to
Are We Alone
Hosted by Dr. Seth Shostak
Live Sunday nights at 7pm PST
(Check your local listings)
or
visit www.seti.org/radio
for more information
Second Quarter 2005 - Celebrating our 20th Anniversary

Astrobiology
Artist’s concept of an asteroid striking
near an inhabited region.
© David A. Hardy/ www.astroart.org
Planetary Defense in Space
by Claudio Maccone
Saving the Earth from collision
with asteroids and comets is the
number one imperative for all
those who care about the survival
of humankind. Unfortunately, this
deadly threat was not clearly perceived until
1980, when the American Nobel laureate
Louis Alvarez suggested that the dinosaurs
were wiped out by the collision of a ~20 km
asteroid about 65 million years ago.
Ever since, a few scientists of good will
have tried to convince their governments
that something must be done (the set of all
such actions is called “planetary defense”),
but without any significant success so far.
Apart from the obvious lack of funding, the
problem of how to divert an asteroid threat
is so difficult to tackle that even the scientists
don’t know exactly what to do, let alone
the managers of the national space agencies
and the various military establishments.
Also, movies like “Armageddon” and
“Deep Impact” have dramatized the story,
but the solutions they portrayed are simply
impossible because no Shuttle would be capable
of reaching so far into space, and with
such short notice.
In 2002, this author put forward a new
idea: orchestrate planetary defense from
outposts in space, rather than sit and wait
on the Earth. This would give us at least
a bit more time (days) to try to divert asteroids
by shooting missiles against them
from two space bases, best located at the
Lagrangian points L1 and L3 of the Earth-
Moon system. The author showed that:
(1) This defense system would be ideal for
deflecting small impactors, less than
1 km in diameter. These are the most
difficult ones to detect far in advance,
and with sufficient orbital accuracy.
(2) The deflection is achieved by pure
lateral push (momentum transfer).
No nuclear weapons in space would
be needed. This is because the missiles
are hitting the impactor at the
optimal angle of 90° from their arrival
direction.
(3) In case one missile was not enough to
deflect the impactor off its collision
trajectory, the new, slightly-deflected
impactor can be hit at 90° by another
missile. So, a sufficient number
of missiles could be launched in a
sequence from L1 and L3 to finally
throw the impactor off its collision
trajectory with Earth.
The Five Earth-Moon
Lagrangian Points
In 1772, Joseph Louis Lagrange demonstrated
that there are five positions of zero
gravity in a rotating two-body system, like
the Moon around the Earth.
Three are located on the line joining
the two massive bodies, and are nowadays
called “colinear points,” or L1, L2 and L3,
as shown in Figure A. Two more points
(L4 and L5) form equilateral triangles with
the two massive bodies, and so are called
“triangular points.” The distance to L1
is about 32,300 km, and to L3 is roughly
382,000 km.
10
SETI Institute Explorer

Figure A - The five Lagrangian points
of the Earth-Moon system and their
distances from Earth and Moon
expressed in terms of R, the Earth-Moon
distance (supposing the Moon’s orbit to
be circular).
Figure B - The two families of confocal
ellipses and confocal hyperbolas.
Trajectories for Best Deflection
The best trajectories for deflecting impactors
involve launching missiles from either
of two colinear Lagrangian points, L1
and L3.
Consider a family of ellipses and a family
of hyperbolas that have all the same two
foci, said to be “confocal.” The great property
of confocal conics is that any pair of
different confocal conics, namely one ellipse
and one hyperbola, always intersect
each other at angles of 90°.
Consider one of the two foci, for example
the one on the left. Imagine the Earth
is situated there. Then both the confocal ellipse
and the confocal hyperbola are trajectories
(paths) that moving bodies around
the Earth follow naturally, because of Kepler’s
First Law.
Now imagine that a dangerous impactor
arrives from infinity, namely from outside
the gravitational sphere of influence
of the Earth. So, it must follow a hyperbolic
trajectory with respect to the Earth, with
Comet Wild 2 is about five kilometers
(3.1 miles) in diameter.
the focus of this hyperbola located just at
the center of the Earth.
The ellipse confocal to the impactor’s
hyperbola is the path of a missile launched
against the incoming impactor from any
point in space, but better from the two colinear
Lagrangian points L1 and L3, each
located on one side of the Earth for defense
on both sides. The selection of the colinear
Lagrangian points L1 and L3 as space bases
for missiles is now self-evident: they ensure
the cylindrical symmetry of the problem
around the Earth-Moon axis. So, the direction
in space from which the impactor is
arriving becomes irrelevant: we will just
be studying confocal orbits in the Earth-
Moon-asteroid plane.
Being confocal, the missile’s ellipse is
automatically orthogonal to the impactor’s
hyperbola, meaning that the collision of
the missile with the impactors always occurs
at a right angle with the impactor’s
path. This is really the best we can hope for,
since the missile’s full momentum is then
transferred to the impactor sidewise.
Finally, if one missile fails to sufficiently
deflect the impactor, we can always send
additional missiles along the new ellipse
that is confocal to the new and slightly deflected
impactor’s hyperbolic path. Once
again, the mathematical representation of
the trajectories matches perfectly with the
physical problem of diverting impactors.
Ellipses for Missiles Shot from
L1 and L3
NASA/JPL-Caltech/NOAO
Figure C (which is not to scale) shows
an example: the incoming impactor is
missing the Earth (represented by the
larger circle located at the origin), but is
of course deflected along an hyperbola. A
missile shot from the Lagrangian point L3
(the smaller circle on the left) can hit the
impactor before it approaches the Earth,
colliding with it at an orthogonal angle. In
Figure D is shown an actual impact trajectory.
But a missile shot from the Lagrangian
point L3 along the shown ellipse, confocal
to the impactor’s hyperbola, could
rescue humankind. Similar considerations
apply to missiles shot from L1.
Political Problems and the Lagrangian
Points
The Cold War ended about ten years
ago, but many people still have Cold War
attitudes. Since nuclear weapons in space
are forbidden by international treaties, a
proposal to locate missiles with possible
nuclear warheads at the Lagrangian points
Figure C - Impactor missing the Earth,
and elliptical path of the missile shot at
it from L3. The orthogonality of the two
paths at their collision point is evident.
Figure D - Impactor hitting the Earth.
Before it reaches the Earth, it could be
diverted by the collision of a missile
shot from L3 along the shown ellipse,
orthogonal to the impactor’s path to
achieve maximum deflection.
L1 and L3 would immediately be perceived
as an attempt to revive the Cold
War.
see PLANETARY, pg. 13
Second Quarter 2005 - Celebrating our 20th Anniversary 11

Astrobiology
Artist’s Concept of Deep Impact’s
Encounter with Comet Tempel 1
NASA/JPL/UMD
Reacting to Disaster
by Douglas Vakoch
The scenario is familiar from Hollywood blockbusters
like Armageddon and Deep Impact. A massive asteroid
– perhaps ten miles in diameter – is headed straight
for Earth. An all-out effort to deflect it is mounted. If
the mission succeeds, civilization as we know it will
continue.
But if natural human reactions to threats interfere, the ending
could be far from uplifting. If fear and denial postpone an adequate
response, dust and debris could make the daytime sky look like
night, the Earth’s surface could be razed by a global firestorm, and
tsunamis could obliterate coastal cities.
In theory, threats from space may be detected far in advance
of their arrival, giving plenty of time to deflect them (see pages
10 - 11) or at least prepare for the aftermath. But that’s in theory.
“What we may actually get,” says psychologist Albert Harrison, “is
an obsessive focus on a very constricted range of options, a refusal
to consider or integrate new data, defensiveness that prevents decision
makers from appreciating threats and developing alternatives,
and panicky, ineffective last-minute choices.”
The result would be devastating. “In some respects,” Harrison
suggests, “post-impact Earth may resemble an off-world destination:
a dangerous place bombarded with harmful forms of radiation,
a toxic atmosphere, and little or no useful vegetation.” If some
part of humanity survives, its future may be bleak. In the case of
extreme destruction,
Harrison says, “hopes
generated by looking
forward to emerging
from shelter will be overpowered
by the realities
of living on a dead and
barren planet.”
The Human
Response
As a social psychologist
at the University of
California at Davis,
Harrison has long
contemplated the impact
of space, ranging from longduration
spaceflights to
the societal implications of
12
SETI Institute Explorer

detecting life beyond Earth. His emphasis
is squarely on the human factor, as is
evident from the subtitles of several of his
books, including Spacefaring:
The Human Dimension and After Contact:
The Human Response to Extraterrestrial
Life. Recently, Harrison has turned his attention
to a different sort of impact from
space: the threat of a massive Near Earth
Object (NEO) that could wipe out civilization
as we know it. “If volcanic activity or
a NEO strike were sufficiently energetic to
produce the equivalent of a nuclear winter,”
Harrison says, “there would be no
speedy return to normal.”
At some level, we can anticipate life in a
post-impact world by looking at other natural
disasters. But the scale of destruction
makes many comparisons irrelevant. We
might expect to see heroic acts of altruism
and charity following such a catastrophe,
for example, but the magnitude of the devastation
may limit the role that good intentions
can play. “Following a major NEO
impact,” Harrison explains, “there may be
no rich people to aid the poor.”
But given our natural ways of coping
with disasters, fear and denial may be the
critical factors that threaten humanity’s
very survival. Learning of an impending
NEO impact might well lead to responses
akin to those observed by psychiatric
social worker Terrance O’Connor when
people face environmental problems – or
refuse to face them. “Avoidance reactions
are common,” he notes. “Most boil down
to ‘I don’t want to hear about it,’ or
‘It’s not my responsibility.’ Some
people convince themselves
that ‘it’s not happening.’”
Clinical psychologist Sarah
Conn describes a similar
reaction to threats. “We feel
either overwhelmed by or
removed from what we
learned about environmental
deterioration,”
she suggests. “We become
helpless or indifferent in
the face of it, and unable
to respond except with
numbness and denial.”
In the face of
an impending NEO
impact, similar denial
may have irreversible
consequences.
Strategies for Survival
What then should we do if danger is
upon us The key, Harrison notes, is to
remain open to new information that
pours in during the weeks, months, and
years following the first detection of a
menacing NEO.
Such openness will be difficult to maintain
in tense and ambiguous times. In spite
of our natural tendency to choose quickly
one plan of defense and stay with it, it will
be critical to evaluate alternative strategies
as updated information is received.
At each step of the way, if we can
anticipate our automatic responses, we
can beware of their potential problems.
For example, a natural tendency will be to
focus on the view of the majority, excluding
alternative solutions. And yet, innovative
approaches that take into account
new data or different perspectives may be
the key to survival. But what, practically,
can we do to promote more productive responses
First, we need to be aware of our
tendency to latch quickly onto one answer,
even when subsequent information calls it
into question. To guard against such uncritical
acceptance of one position, some
key decision makers may be selected to
play the role of devil’s advocate. By sanctioning
the role of dissident, unpopular
but potentially vital alternatives can be
explored, providing one safeguard against
monolithic “groupthink.”
“Of course the ultimate protection for
our race,” suggests Harrison, “is dispersal
beyond our home planet.” In tandem
with preparations to protect the welfare
of Earth-bound people, colonies might
also be established on other planets. “Dispersal
throughout the solar system will
not necessarily protect us from all risks,”
he acknowledges, “but we would be far
better protected from extinction than we
are right now.”
Dr. Douglas Vakoch
Director of Interstellar
Message Composition
SETI Institute
Dr. Vakoch is a clinical
psychologist who serves on
the International Academy of
Astronautics’ Study Group on
Earth-threatening Asteroids
and Comets.
PLANETARY, continued from pg. 11
So, it is realistic to take for granted
that any such proposal, if put forward officially
to any country’s political institutions,
would immediately be rejected by
politicians as well as by the public at large.
Just think of all the problems that NASA
and ESA are having with ecologists simply
in order to put Radioactive Thermal Generators
(RTGs) aboard their spacecraft.
Ecologists against RTGs actually support a
narrow-minded view of ecology, based on
the oversimplified belief that whatever is
“nuclear” is “dangerous.” This is the heritage
of the Cold War and of all wars that
went before it.
The threat of impactors creating havoc
on the Earth’s surface is real, as was well
proven by the Tunguska event of 1908.
However (and fortunately!) the Tunguska
disaster took place in a lonely forest of Siberia,
and so there were no casualties. In
addition, back in 1908 not even the scientific
community was ready to accept that
such an disaster could possibly occur, not
to mention that governments and lay people
were not ready at all to learn the Tunguska
lesson. So, everything went on just
as if nothing had happened at Tunguska,
until the first scientists took some notice
in 1927.
All this shows well that humankind still
is not yet ready to face the threat of impactors
and comets. Only when humans stop
planning and conducting big wars among
themselves will governments have more
time to think about new dangers coming
from space. And ecologists will mature to
the point of not hampering their governmental
agencies in putting up missiles and
weapons in space if these will prevent dangerous
asteroids and comets from obliterating
humankind, including the ecologists
themselves.
In conclusion, this new consciousness
about a danger that affects the whole of
humankind will sooner or later surface for
the vast majority of people, and prepare
them for the challenges of a new millennium.
Dr. Claudio Maccone
Mathematician
Dr. Maccone is a member of
the International Academy
of Astronautics, as well as
an active member of its SETI
Permanent Study Group. He
lives in Torino, Italy.
Second Quarter 2005 - Celebrating our 20th Anniversary 13

Astrobiology
Cosmic Catastrophe and
Armageddon
by Mark Brake and Martin Griffiths
Modern science has known
for some time that Earth
is continually bombarded
by a celestial rain of
cosmic debris. Much of
it is either fine dust, or larger objects that
mostly burn up in the atmosphere, and
are of little consequence to the terrestrial
environment. But occasionally, larger
objects survive the journey through the
atmosphere, finding their way to the ground
where they are known as meteorites.
Giant asteroids and comets
pose a threat to the entire
planet; one that is now
being taken very seriously
due to apocalyptic evidence
from the fossil record.
Every couple of years such meteorites cause
damage: they punch holes in houses, or
take the wing off a car in Queens, New
York. Well not merely a particular car in
Queens of course; this is just one instance
of the many reported! Meteorites have also
been known to brain the odd dog; in 1911
near the town of Nakhla, Egypt a Martian
meteorite caused the only known case of a
canine fatality due to a cosmic object.
Such events are newsworthy only
because of their esoteric rarity. Yet what is
disturbing about this cosmic rain is that the
distribution of this meteoritic material has
no large-size cut-off, and, unlike other terrestrial
natural hazards, a collision with a
large object from space may have extreme
consequences for our planet. Estimates
indicate that every few 100,000 years or
so, impactors such as comets or asteroids
more than a mile in diameter strike Earth
with serious global environmental consequences.
Research also shows that every 100
million years or so, a cosmic impactor 5 to
10 miles across strikes, with consequences
so terrible that most species are threatened
with extinction. It is plausible that an even
larger object, perhaps 25 miles across or
Artist’s concept of a meteor shower in
prehistoric times.
© David A. Hardy/ www.astroart.org
more, will strike the Earth during our Sun’s
lifetime with the possibility of sterilizing
the surface of our planet.
This astronomical discovery has generated
a rather belated, though nonetheless
welcome, program called Spacewatch that
attempts to give prior warning of any impactors
that come within striking distance
of the Earth. The destructive scenario envisioned
from such impactors has given
a more contemporarily relevant ring to
the words apocalypse and Armageddon.
The projected cosmic catastrophe is of
biblical proportions, and differs from all
other natural hazards in two ways:
4 the potential consequences of a
major impact exceed any other
known natural or man-made
hazard (including nuclear war);
4 the probability of a major
impact occurring in a politically
relevant time scale (say, during
our lifetimes) is extremely low,
but not outside the bounds of
possibility.
14
SETI Institute Explorer

The impact hazard is, therefore, a terrifying
prospect that remains the ultimate
high-consequence, low-probability hazard
that could lead to Armageddon. However,
trying to predict such a catastrophe is not
easy, and predictions incur various associated
risks. According to astronomers at
Spacewatch:
“... this peril is evolving from one that was
almost unknown two decades ago (hence a
serious impact would certainly not have been
predicted) to one in which 75% of the risk
could, within two more decades, be predicted
so exactly that mitigation measures within
our technological capability could be applied
with a high degree of effectiveness. For the
remaining 25%, the prediction would
either be too late to mount more than partial
countermeasures or there might be a wholly
unforecast ‘act of God’ if a comet were suddenly
to appear from the direction of the Sun,
therefore rendering it invisible to all observational
techniques here on Earth.”
(History of the Asteroid/Comet Impact
Hazard, Clark R. Chapman, 1998)
Predicting Armageddon is more than
producing an array of facts and figures;
it involves genuine concern based upon
evidence of recent impacts. Although
astronomers and insurance underwriters
use the term “act of God,” a catastrophe
of this type is simply a hazard of living in
a planetary system. A number of impacts
are known to have occurred in the last
century. The first impact was in Siberia, at
a place known as Tunguska in June, 1908.
The second was in Brazil in 1930. Thankfully,
both areas are unpopulated, and not
a single human being was killed. But the
consequences could have been very different,
and the threat brought to the world’s
attention sooner, if these impactors had demolished
a city or town.
Now that the threat of NEOs (Near Earth
Objects) is out in the open, greater attention
is being paid to astronomical programs
that search for these threats from space.
Astronomers are able to counter the content
of otherwise startling media reports,
such as the one proclaiming a forthcoming
“near-miss” of Earth by a mile-wide asteroid,
predicted for the year 2028 with initial
reports suggesting a serious possibility of
actual impact. This generated front-page
news in March 1998. Since these headlines
appeared, two major blockbuster science
fiction films, Deep Impact and Armageddon,
released in the summer of 1998, helped
raise the profile of this type of threat, particularly
among politicians and populace.
Spacewatch is now a relatively major
player in impact detection. Although at
present our telescope technology could
provide precise predictions about where
a potential impactor is in space, they
cannot tell us where on Earth such an
impact might occur. There are also uncertainties
regarding such forecasting, almost
akin to the uncertainties of forecasting
events such as hurricanes and tornados,
global warming, the ozone hole, and El
Nino – we cannot predict results in advance,
and all we are left with are models
of worst-case scenarios. Global warming
and the destruction of the ozone layer
are ‘invisible’ problems in the sense that
people are unaware of their stealthy effect
on our environment; the detection of an
asteroid and its subsequent impact will be
a highly ‘visible’ problem which will raise
questions about how individuals, society,
and political institutions prepare for, and
conceivably respond to, predictions of such
a horrific, but unlikely disaster.
Nevertheless, astronomers dare not
appear to be like Aesop’s “boy who cried
wolf” by playing on fears and making banner
headlines whenever an object passes
close by, but far enough away to cause no
harm. To do so would mean a loss of credibility
in an arena in which they conceivably
might someday have to forecast an event
that would deserve to be taken seriously at
the highest public and governmental levels.
Getting out of the way
What could be done about an impending
impact According to David Morrison
of the NASA Ames Research Center, once
we know that an impending impact event
is likely, we might attempt to deflect the
impactor from its collision course with the
Earth. This could be achieved with a highyield
nuclear weapon, which could deflect
the impactor slightly from its trajectory if
the weapon is delivered in plenty of time,
months or years before the impact event. At
present there is no rocket vehicle capable of
lifting a high yield warhead into deep space,
and one is unlikely to be developed due to
the high cost factor in the face of such a low
risk event.
The alternative approach to this threat
would involve destroying the potential impactor
completely. Depending on the size of
the incoming object, a high-yield warhead
may be able to accomplish this goal. The
problem of delivery and synchronization of
the explosions have yet to be overcome, and
few scientists are worried enough to provide
alternate solutions.
Giant asteroids and comets pose a threat
to the entire planet; one that is now being
taken very seriously due to apocalyptic evidence
from the fossil record. It is believed
than an impactor approximately 6 miles in
diameter impacting the Earth was a contributory
factor in the extinction of the
dinosaurs some 65 million years ago. The
primary evidence, discovered by the late
physicist Luis Alvarez and his son Walter, a
geologist, is a layer of the element iridium
laid down in sedimentary rock in Gubbio,
Italy, at about the time the giant reptiles
disappeared. Iridium is rare on the Earth’s
surface but far more common in asteroids.
If an enormous chunk of space rock hit
the planet, the Alvarez team theorized, it
would have largely disintegrated, casting a
pall of iridium‐rich dust and other debris
over the world that could have lasted for
months. Deprived of sunlight by this natural
version of nuclear winter, plants, and
the animals that fed on them, would have
died in significant numbers. And when the
dust finally settled, the iridium it contained
would have formed just such a layer as the
Alvarez team found.
Smoking Gun
Since publishing their findings in 1980, a
host of geologists, paleontologists, astronomers,
and physicists have looked for further
evidence, including a crater of similar age to
the dinosaur extinction which could be the
‘smoking gun’ of such an impact. The crater
was eventually discovered by Glen Penfield,
a geologist working for PEMEX, the Mexican
oil company that was drilling in the
Yucatan peninsula. What Penfield uncovered
was a large, 65 million year old crater,
120 miles in diameter. Known today as the
Chicxulub Crater, Penfield uncovered this
ancient impact site using instruments that
sense gravitational and magnetic anomalies.
An in-depth study of various geological
features throughout the western hemisphere
has revealed the dreadful details of
the impact. The force of the collision initially
sprayed molten rock and debris worldwide,
which re-entered the atmosphere and
heated it to 500 – 900 F, killing off most animal
life within a matter of hours or days.
Plant life and smaller creatures who may
have survived the initial impact were killed
as vaporized minerals thrown into the upper
atmosphere took months or years to
settle, creating a permanent ‘winter’ which
plunged the ecosystem into a freeze from
which few species emerged. The dinosaurs
never stood a chance.
Second Quarter 2005 - Celebrating our 20th Anniversary 15

Board Profile
Most astronomers downplay the threat
of such events, and statistically they are
correct to do so. According to David Morrison,
we have a 1 in 20,000 chance of such
an impact event happening within our
lifetime, and as our technological capability
to discover and deal with such threats
grows, so do our chances of avoiding this
kind of apocalypse. However, the current
scientific debate about protecting the Earth
from such impacts is essentially the latest
chapter in the long and violent history of
our planet. Morrison recommends that we
simply get on with our everyday lives with a
fateful acceptance of the facts.
Conclusion
We have to accept the apocalyptic nature
of some events that have happened to Earth
in the past, and may threaten us again in
the future. As this threat is perceived, man
stands at a crossroads in his evolution.
For the first time in history, a species has
emerged on this planet that has a technological
capability that could defer this menace,
and even obliterate it from our collective
consciousness. If this is so, then Earth
will continue along its path of life’s history,
and perhaps apocalypse will come through
measures that are unforeseeable as human
evolution continues. However, such a form
of apocalypse will hardly be catastrophic,
but will result from minute changes over
long periods of time.
Whatever the case, apocalypse and catastrophism
in their various forms will always
be a part of cosmological and astronomical
study because they generate wonder about
the universal home we inhabit. In the final
analysis, we continue to be inspired and
awed by the physical processes that make
up our universe, and we realize, despite our
imposed self-importance, that we are just a
very small part of a cosmos that interacts
with humanity in ways that the ancients
could never foresee.
Mark Brake and Martin Griffiths
University of Glamorgan
United Kingdom
Mark Brake and Martin
Griffiths are members of
NASA’s Astrobiology Science
Communication Group at the
Centre for Astronomy and
Science Education, University of
Glamorgan, United Kingdom.
This article originally appeared
in proceedings from the
“Apocalypse 2000” conference.
Inside the Boardroom with
Alan Bagley
Seth Shostak
The successful stewardship of the
SETI Institute depends upon
its Board of Trustees, which
counts among its 17 members
two Nobel Prize winners,
four members of the National Academy of
Sciences, one member of the National
Academy of Engineering, and several current
and former Fortune 500 business
executives. This series profiles our Board
members and gives insight as to why such
important people have chosen to be part of
the SETI Institute.
When did you become aware of
the SETI Institute’s work, and what
initially intrigued you
Sometime around 1965, Barney Oliver,
Director of Research at Hewlett-Packard
Company, attended a meeting where Frank
Drake brought forth his now-famous equation
and used it as an agenda for a scientific
symposium. Barney told us at HP about
that meeting. He was greatly impressed by
the logic in the equation and the caliber of
scientists there to discuss the probability of
life in outer space. His interest in the SETI
concept grew. Before long he had shown us
the advantages of using a large radio-telescope
array in the search for intelligent life.
At one point, when the Institute was
receiving NASA funds, I was one of the
people Barney invited to attend a three-day
review of scientific progress at the Institute.
I think the comments of our review committee
were useful in confirming a certain
bureaucratic sickness that had crept in.
That problem was properly medicated. In
that review process, I became more aware
of the excellent scientific and engineering
talent engaged in the search. Later, when
asked to take a place on the Board, I was
delighted to accept.
What area of research most intrigues
you
I am intrigued by the broad research being
carried on at LITU (Life in the Universe),
in the search for any possible cosmic life
forms.
What do you see as the greatest
challenges for the Institute
The Institute has difficulty in obtaining sufficient
funding to carry on its programs. As
we face that challenge, we must be sure to
maintain absolute scientific honesty in any
promotions used for funding as well as in
all of our public relations efforts.
What do your friends say when you
tell them you’re involved with the
SETI Institute
Some of my friends are a bit skeptical regarding
the odds against our getting any
“return on investment.” I like to point out
that discoveries in astronomy are slowly
but steadily improving those odds. Also, it
is worth noting that the world is better today
because of risk-takers. Among some of
the more successful in that regard are Dave
Packard, Bill Hewlett, Gordon Moore, Barney
Oliver and Paul Allen, all of whom have
placed their bets on SETI. To bet against
them would seem unwise.
Alan Bagley
Board of Trustees, SETI Institute
Mr. Bagley spent 37 years as
a Hewlett Packard Executive
including general manager. He
is the founder of the Los Altos
Community Foundation.
16
SETI Institute Explorer

COSMIC NEWS
NASA/JPL-Caltech/NOAO
In April, the SETI Institute hosted an exhibit
and sale of Chinese brush and finger
paintings by artist and Institute supporter
Inger Friis. Mrs. Friis donated proceeds
from the art sales to a scholarship for
summer interns at the Institute. Born in
New York in 1910 to Danish parents, Friis
began painting very early in life, and has
received numerous awards for her artwork,
which has been displayed in museums
from New Jersey to Taiwan.
Jill Tarter attended the Time100 Bash in
NYC April 19 to receive her award as one
of Time Magazine’s 100 most “influential
and powerful people” of 2004. As mentioned
in a previous issue of Explorer, Dr.
Tarter was chosen in the “Scientist and
Thinker” category for her leadership role
in the scientific search for evidence of life
on other worlds, and for her efforts to
promote scientific literacy among youth,
particularly girls and young women.
May was a busy time for SETI Institute
scientists. Jon Jenkins spoke at UCLA on
May 13. Nathalie Cabrol reported on the
progress of the Mars Exploration Rovers
at Foothill College as part of the Silicon
Valley Astronomy Lecture Series. On May
19 Seth Shostak was the featured scientist
for Ask a Scientist, a free lecture series held
each month at a café in San Francisco.
Jill Tarter spoke at the CEN meeting in
Seattle on the 25. Ken Souza was part of a
panel discussion at the International Satellite
Convention on May 31.
On May 14 the SETI Institute held our
second annual Science Day event. A
day of lectures featuring scientists and
educators from The Center for the Study
of Life in the Universe, The Center
for SETI Research, and Education and
Public Outreach, as well as several guest
speakers. Over 300 guests attended the
event, held at NASA Ames Research Center
in Mountain View, California. Become
a member of TeamSETI to receive invitations
to events like this, and more!
The Luncheon Society of San Francisco
welcomed Jill Tarter as their speaker on
June 11. Peter Backus was the featured
speaker at the IEEE EMC Society meeting
in Michigan on June 15.
On June 16, Seth Shostak was a distinguished
lecturer at the AIAA meeting in
Houston, and spoke at the Salado Institute
later that week. Douglas Vakoch was
a panelist(via videolink) at the Dana Center
in London. On June 19 he presented
his research at the Society for Interpersonal
Theory and Research conference in
Montreal, Canada.
On June 22, Principal Investigator Jon
Jenkins spoke at the NASA Explorer
Schools (NES) workshop at Ames Research
Center in Mountain View about
the Kepler Mission.
On June 28 the SETI Institute welcomed
students from the National Youth
Leadership Forum on Technology, an
annual program that brings together
the most gifted high school students
from across the United States with industry
professionals and educators for a
behind-the-scenes view into the field of
technology. The Institute’s participation
included both a site visit in which students
heard presentations from Jill Tarter, Peter
Backus, Emma Bakes and Tom Kilsdonk,
as well as interactive seminars at
the Fairmont in San Jose held by Institute
Principal Investigators Margaret Race
and Nathalie Cabrol. Postcards from Saturn
is the subject of Mark Showalter’s
talk at the Mt. Tam Astronomy program
on July 9.
As mentioned in our last issue, the Astrobiology
Summer Science Experience for
Teachers (ASSET) program will take place
July 10-16. A science and curriculum institute
for high school science teachers, the
workshop features a combination of cutting
edge science, inquiry-based teaching
and learning, and leadership skills development.
The program includes presentations
by leading astrobiology researchers
from the SETI Institute, NASA, and the
California Academy of Sciences.
Also in July the SETI Institute will host
the NAI First Workshop on the Habitability
of Planets Orbiting M-Stars. The workshop
runs July 18-20 and will feature many of
the Institute’s scientists among the working
groups.
The SETI Institute’s Frank Drake contributed
the afterword to a new astrobiology
book featuring text by Ray Villard
and Lynette Cook’s stunning artwork of
extrasolar worlds. Infinite Worlds – An
Illustrated Voyage to Planets Beyond Our
Sun includes 78 full-page color paintings
and 38 color photographs, in tandem with
Villard’s commentary on the current state
of astronomy, and what may lie in the
future.
Second Quarter 2005 - Celebrating our 20th Anniversary 17

Astrobiology
Magnetic Field Reversal
The Andromeda Galaxy
NASA/JPL-Caltech/NOAO
Here Comes
Andromeda
by Laurance Doyle
Looking at the last term of the Drake Equation, we see that it relates to the lifetime
of technological civilizations – how long they last as technological (meaning
interstellar communicating) entities. The three biggest considerations for
our civilization at the moment could be characterized as a) getting along with
each other, b) getting along with the environment, and c) staying technologically
alert for large-scale concerns from space.
Some dinosaurs were bipedal, had opposable claws, and were pretty intelligent—so
why didn’t they, for example, invent space travel Well, that’s a topic for another essay.
Meanwhile, let’s stick to a few of the things we might want to deal with “out there” at
various times in the future, from a few thousand to a few billion years from now.
The Earth’s magnetic field is thought to
be generated by a dynamo effect – that is,
the movement of charged particles in its
huge iron and nickel core as it spins. Other
planets have magnetic fields also, and there
seems to be some relationship between the
strength of the magnetic field and the size
and spin rate of the magnetic core. Jupiter,
with a huge core and a 10-day rotation
period, generates a massive magnetic field,
for example, and spacecraft sent there have
to be specially built to withstand this intense
field. You may remember the science
fiction movie Outland with Sean Connery
stranded in a mining colony on Io, one
of Jupiter’s moons. However, Io would be
uninhabitable since the magnetic field of
Jupiter causes a 5 million ampere electric
current to flow through it.
However, magnetic fields can also be
helpful. They can protect the inhabitants
of the planet from high energy particles
from, for example, the solar wind. (Yes, the
Sun has a wind component, one that can
be used to power solar-sail spacecraft in the
near future.) When the high energy particles
from the Sun encounter the Earth’s
magnetic field, they are deflected toward
the poles, causing beautiful auroral “curtains”
of color as they hit the atmosphere.
Without the magnetic field of the Earth,
these high energy particles could do damage
to biology on Earth.
When rocks containing magnetite cool
from volcanoes or are baked (as in clay pottery),
they record the direction of the magnetic
field of the Earth at the time of cooling.
It turns out, from examining rocks of
various ages, that the Earth has reversed its
magnetic field many times – the last about
750,000 years ago (the average being about
every few hundred thousand years). Recent
measurements of ancient pottery and other
evidence suggest that the Earth’s magnetic
field may be declining – perhaps getting
ready for an overdue reversal. This could
take place within the next couple of thousand
years. If the Earth’s magnetic field is
just beginning to reverse, it would certainly
be important for us to protect ourselves
from the high energy particles of the solar
wind and of space. It would not be as devastating
an event as, for example, a comet
impact, but it does indicate that we do not
have the luxury of indulging in another
Dark Age over the next thousand years
or so. If civilization is to maintain itself,
we need to be on our technological “toes”
pretty much from now on.
18
SETI Institute Explorer

http://www.oldstarlight.com
The Moon absorbs any transfer of orbital to rotational angular moment, preventing
the Earth from flipping.
Moon Stabilizes Earth’s
Rotation
The most popular theory for the origin
of the moon is that it came from the
Earth. We can calculate evolutionary histories
of the moon’s orbit as it moved away
from the Earth after formation. (It is still
moving away due to the Earth’s tidal pull
at about one inch per year. The majority of
the tidal dragging comes from Earth’s rotational
slowdown, with most being caused
by waters dragging over the fairly shallow
Bering Sea.) In doing some of these kinds
of calculations for Mars, it was discovered
that the direction of Mars’ rotational axis
could flip rather suddenly. Now this is not
the normal “precession” (as it is called) of a
few degrees that changes, for example, our
north star though the millennia. Mars was
calculated to have flipped its rotation axis
up to 90 degrees in as little as a couple of
million years. This was a result of the orbital
angular momentum, under certain
circumstances, being transferred to the
rotational angular momentum and causing
a coupling that led to such a flip in rotation
axis direction.
So why has this not occurred on Earth,
whose axis has seemingly not flipped by
more than a few degrees The apparent
explanation is that the Moon absorbs any
transfer of orbital to rotational angular
moment, preventing the flip.
Would such a flip be important It could
get very serious – like the time a couple
of hundred million years ago when all the
continents were combined into one big
continent called “Pangaea”—if the Earth’s
rotation axis flipped such that this one big
continent became a polar continent like
Antarctica. So, it would appear that a moon
is required for a stable planet with life.
This was perhaps surprising news to
folks that would like to see habitable planets
widespread in the galaxy requiring, as it
does, both an earthlike planet in the circumstellar
habitable zone as well as a fairly large
satellite. This would seem to rule out habitable
planets being very common. However,
additional research into the rotational histories
of the planets shows that the Earth
used to spin a lot faster. If the earth spins
faster, that also acts as a protection against
flipping of the rotation axis. So, perhaps if
the moon had not come off the Earth, our
world would still be spinning fast enough
to stabilize itself against flipping. Thus
there may be many other habitable planets
without a large moon, but the inhabitants
will have even fewer hours in their day than
we do.
The moon, of course, is now perfectly
placed to exactly cover the solar disk during
eclipses. This perfect fit has allowed,
for example, a test of General Relativity,
the uncovering of the element helium,
and the discovery of the solar corona. And
clearly the moon has been a great stimulus
and practice ground for our first efforts at
space travel. However, moving out at an
inch a year, in about 1.6 billion years the
moon will no longer be able to stabilize
our planet’s spin. We’ll have to be ready for
a climatologically wild ride by then unless
we figure out what to do. Eventually the
Earth will have the same rotation period as
the moon’s orbit (i.e., the day will equal the
month) and then the moon may be expected
to fall back toward the Earth, forming a
ring perhaps not dissimilar to those around
Saturn. It will, no doubt, be a great show.
see ANDROMEDA, pg. 20
SAVE THE DATE
Sunday September 25, 2005!
Join us for
the SETI Institute’s
Annual TeamSETI
Ice Cream Social
To sign up for TeamSETI
visit: www.seti.org/teamseti
Second Quarter 2005 - Celebrating our 20th Anniversary 19

ANDROMEDA, continued from pg. 19
Here Comes Andromeda
We could talk about many more interesting
phenomena, but perhaps the most
spectacular will be the merging of the
Andromeda spiral galaxy with the Milky
Way in about six billion years. Although no
stars will likely touch (the spacing between
stars is huge), this interaction will most
certainly gravitationally affect every star
in both galaxies. The Milky Way, in its 12
billion year history, has swallowed up many
smaller galaxies, but such a merger will be
a unique experience. Every star is thought
to have a cloud (called the “Oort Cloud” in
our solar system) that consists of about a
trillion comets. As the two galaxies merge,
these comet clouds will get scrambled, causing
increased impacts onto each star’s inner
planets. Billions of stellar systems being tidally
flung around may also cause instability
in the orbits of the planets around them.
Nicolai Kardeshev has suggested that
there could be three classes of civilizations
– Type I controlling the resources of
its planet, Type II controlling the resources
of its star, and Type III controlling the
resources of its galaxy. At the moment we
are estimated to be about type 0.1 or so. A
Type II builds such things as Dyson spheres
(structures encompassing the star so as to
capture all of its energy). Clearly, a Type III
civilization would be needed to deal with
the merging of Andromeda with the Milky
Way.
So, there we have it – some items on
the agenda for the next few billion years.
We have some time for planning, but it’s
important that we stay alert – we really
can’t afford to indulge in another extended
Dark Age, for example. And who knows, we
might make it to Type III before Andromeda
gets here. If not, perhaps some other
species in the galaxy may have gotten it
together enough to help us out.
TeamSETI members can read the unabridged
version of this article online at the member
page at www.seti.org
20
Dr. Laurance Doyle
Astronomer, SETI Institute
Dr. Doyle’s projects range
from the search for terrestrial
extrasolar planets to
information theory. He is also
the president and founder of
PlanetQuest.
Provide For Your Future
and the SETI Institute’s
That’s exactly what Vera
Buescher is doing by creating
a SETI Institute Life Income
Trust.
“I had some stocks that were paying
very little in dividends, but the capital
gains tax on selling them would have
been tremendous. I realized that
making a Life Income Trust with the
SETI Institute would work to benefit
both of us.”
Advantages of a SETI Institute Life
Income Trust include lifetime payments
at attractive rates, plus significant
tax benefits for your charitable
contribution.
Rates from 6% to 11%
Vera Buescher,
a special friend who is thinking of
the SETI Institute’s future.
Fill out the form below and mail it to the SETI Institute to learn more.
Send information on a SETI Institute Life Income Trust
Birthdate(s): ___________________________
Amt: $10,000 $50,000 $100,000 Other
I want to know more about gifts to the SETI Institute that
provide me with income for life.
Send information on including the SETI Institute in my will.
I have already included the SETI Institute in my will.
Name: _____________________________________________
Address: ____________________________________________________
City: _____________________ State: ______ Zip: _______________
Phone: ______________________________
Email: _______________________________
Mail to:
ATTN: Legacy
SETI Institute
515 N. Whisman Road
Mountain View, CA 94043
or
Contact us by email/phone
Email: legacy@seti.org
1-650-961-6633
ask for Karen Randall
Seth Shostak
SETI Institute Explorer

Allen Telescope Array Update
David DeBoer
The entire assembly is carried out
to its pedestal on the end of this
flexible forklift. Pins on the top of
the pedestal align the mounting
“alidade,” and it is then bolted in
place.
David DeBoer
by Dave DeBoer
David DeBoer
Above is the assembled antenna within
the construction tent. The subreflector
has yet to be added and the antenna will
be carried out to its waiting pedestal.
The tent looked so big when it
was first installed. The vaulted
top stands 35 feet above the
ground. It is 40 feet wide. The
door is almost 30 feet high. It’s
gleaming white. In short, it’s a perfect place
within which to build the antennas for the
Allen Telescope Array.
Well, when you build an entire 20 x 24
foot antenna on a pedestal inside of it, all
of a sudden the tent doesn’t look so big.
In fact, the door looks a skosh too small.
But the assembly does fit in the tent; even
the somewhat tricky “flip” needed in the
assembly process cleared the ceiling. It also
fit through the door, with an inch or two
to spare, just as we knew it would. But we
still sighed a bit in relief. Our factory was
in production! And it all went superbly, a
tremendous credit to our chief mechanical
engineer, Matt Fleming, who conceived and
designed the antenna mount and all of the
associated fixtures and hardware.
It has been very gratifying to begin the
emplacement of antennas at the Hat Creek
Radio Observatory site, something which
we’ve been working towards for several
years now. The entire antenna gets assembled
using a series of “fixtures” inside
of this tent. A fancy forklift then picks up
the antenna (complete with the subreflector,
cabling, and electronics), carries it out
to the waiting pedestal and sets it carefully
in place. This procession will continue until
later this year, when the 42 nd antenna in
Phase I goes up. After a short hiatus, the
procession will continue as we proceed
toward our full complement of antennas.
The new cryogenics on the log-periodic
feed have been working flawlessly, cooling
the small low-noise amplifiers that sit at
the focus of each antenna to a very chilly 50
K, about 30 K lower than our design goal.
Since these amplifiers are the first electronic
components that the received electromagnetic
waves have seen in possibly billions
of years, we treat them gently with these
amplifiers. The low temperatures assure
that the thermal wiggles of the electrons
in the device don’t add much noise to the
weak signal.
Once the signals have been amplified, we
can treat the signal a bit more harshly, as
we convert the microwave signals to optical
signals and transport them back to the lab,
where they are converted back to microwave
signals and digitized. Once the signals
are in the digital domain, we can treat
them with impunity. In fact, we clone them
repeatedly. In this way, we can send bit-perfect
copies to several back-end processors
which can individually handle the data to
produce many types of data products useful
for SETI researchers and astronomers.
So, from the large machines installing
the big structures which gently receive
the incoming wave to the small machines
that pick and place the tiny-yet-powerful
digital electronics which manipulate the
signals, the progress is tangible. We all look
excitedly to the near-term and the
burgeoning capability of this pioneering
new telescope.
Dr. David DeBoer
Project Manager
Allen Telescope Array
Dr. DeBoer’s Research and
Development efforts include
the new signal processing
algorithms and new search
technologies that are
incorporated into observing
projects.
Second Quarter 2005 - Celebrating our 20th Anniversary 21

The SETI Institute’s
New Educational Classes
Sign up now for one of our classes, held at the SETI Institute
LIFE IN SPACE
Course #001
Taught by Senior Astronomer Seth Shostak
Course Description:
There is now compelling evidence that many
billions of planets orbit silently and unseen
within the star fields of the Milky Way, including
at least one that’s only slightly larger than
Earth. Could some of these support life
The search for life beyond Earth is ramping
up. Scientists are planning increased reconnaissance
of Mars and some of the moons of the outer
solar system in a hunt for nearby biology, while other researchers
are aiming massive telescopes towards nearby stars as they search
for intelligent beings on other worlds.
In this course, we’ll investigate one of the greatest quests of all
time. We’ll consider (1) why we think life could be as common as
phone poles, (2) how we could find it, (3) whether it’s possible that
life could spread from planet to planet, or star to star, and (4) supposing
we do find biology elsewhere, what would be the effect on
our own society
ASTRO LAB
Course #002
Taught by Senior Astronomer Seth Shostak
Course Description:
Finally, a hands-on course in astronomy! Astro
Lab is different from other informal courses in
sky science. As a student, you will actively participate,
using photos of galaxies, supernova
remnants and stars to do your own “research”
at the classroom desk. Rather than hours of
non-stop lecture, you’ll investigate the expansion
of the universe by measuring it yourself. You’ll
classify stars on the basis of their spectral appearance, and estimate
the age of a supernova. It’s all done with photocopied versions of
real astronomical data.
What do you have to bring to this new course An
inquiring mind and a pocket calculator. All else will be supplied.
Learn astronomy by doing it ... in Astro Lab.
Ages: Adults and Teens age 15 and up
One 2-hour course
Ages: Adults and children age 12 and up
A 4-hour course taught over two evenings
Dates: Tuesday, August 16, and Tuesday, August 23
Time: 7pm-9pm
General Public: $35 per person
TeamSETI members: $25 per person
Dr. Seth Shostak
Senior Astronomer, SETI Institute
Dr. Shostak is a Senior Astronomer at the SETI Institute. He
has an undergraduate degree in physics from Princeton University,
and a doctorate in astronomy from the California Institute of
Technology. For much of his career, Seth conducted radio astronomy
research on galaxies, and has published approximately fifty
Seth Shostak
Date: Thursday August 25
Time: 7pm-9pm
General Public: $35 per person
TeamSETI members: $25 per person
papers in professional journals. During more than a decade, he
worked at the Kapteyn Astronomical Institute, in Groningen, The
Netherlands, using the Westerbork Radio Synthesis Telescope. He
also founded and ran a company producing computer animation
for TV.
Seth has written several hundred popular magazine and Web
articles on various topics in astronomy, technology, film and television.
He frequently lectures on astronomy and other subjects,
and gives approximately 70 talks annually at both educational
and corporate institutions. For the last six years, Seth has been a
Distinquished Speaker for the American Institute of Aeronautics
and Astronautics.
Seth has written, edited and contributed to a half dozen books.
His first popular tome, Sharing the Universe: Perspectives on Extraterrestrial
Life (Berkeley Hills Books) appeared in March, 1998. In
1999, it was chosen as a Book of the Month Club science selection.
He has also co-authored an astrobiology text, Life in the Universe
(Addison-Wesley), and his latest is book is Cosmic Company (Cambridge
Univ. Press). In 2004, he was awarded the Klumpke-Roberts
Prize for the popularization of astronomy.
22
SETI Institute Explorer

3 easy ways to register for classes:
1. Online: http://www.seti.org/classes/
2. By Phone: Contact Jennifer Bugnatto at 650-960-4517
3. Complete the form below and mail with your payment (check or credit card) to:
Attn: Jennifer Bugnatto/Class Registration
SETI Institute
515 N. Whisman Road
Mountain View, CA 94043
(Make checks payable to “SETI Institute”)
Name _____________________________________ Course Number(s) ______________
Address ____________________________________________________________
City _______________ State ____________ Zip__________ Date of Birth ______________
Phone: ________________________ Email address: _____________________________
Method of Payment: rCheck rCredit Card
Card Type: rAMEX rVISA rMastercard
Card# ______________________________________________ Expiration _________
Signature ___________________________________
TeamSETI Member Yes ____ No ____ If you’re not a member, visit www.seti.org/teamseti/ to join now!
Include Member number to receive $10 off each class fee: ________________________
Registration Fees: #Classes ______ x $35 = $ _________
Less TeamSETI discounts if applicable: $ _________
TOTAL FEES Enclosed: $ _________
Quick survey
1. What other class topics would you be interested in _______________________________________________
__________________________________________________________________________________________
2. What other events/benefits would you like to see the SETI Institute offer its members ___________________
__________________________________________________________________________________________
(copy this form for additional registrants, or please enclose a separate sheet of paper with the information above)
Second Quarter 2005 - Celebrating our 20th Anniversary 23

Next Issue:
Extrasolar Planets
Jason Williamson
SETI Institute
515 North Whisman Road
Mountain View, CA 94043
Telephone 650-961-6633
FAX
50-961-7099
Visit us online at:
http://www.seti.org
24
SETI Institute Explorer