PLEASE NOTE:
*
CCNet 145/2002 - 17 December 2002
--------------------------------
"In view of a realistic threat from Near Earth Objects
(comets and
asteroids), The Aerospace Corporation has joined with the
American
Institute of Aeronautics and Astronautics to address technical
and policy
issues relative to the defense of Planet Earth. A new forum,
slated
for February 2004: AIAA's 1st Planetary Defense Conference:
Protecting
Earth From Asteroids, will approach the threat from the
perspective of three
levels of warnings: 1) Short term (less than 10 years warning of
possible
impact); 2) Medium term (10 to 30 years warning); and 3) Long
term (more
than 30 years warning), with an overarching intent to define
several
possible threat scenarios and develop potential responses for
each."
--American Institute of Aeronautics and Astronautics, 16
December 2002
"Disguised as futuristic ants, newly designed artificial
intelligence will be able to venture into the nooks and crannies
of space
as never before possible. They're tiny and weigh in at about 2.2
pounds, but they could fan among the hundreds of thousands of
asteroids
and begin to explore. They're called ANTS -- it's an acronym for
Autonomous
Nano Technology Swarm, a fleet of tiny insect-like spacecraft
which could
cruise all by themselves to the asteroid belt. The ANTS could
provide a
hands-on survey of the asteroid belt to determine which
individual
rocks had the greatest potential to generate the mother
lode."
--Carole Rutland, Ledger-Enquirer, 16 December 2002
(1) PROTECTING EARTH FROM NEO IMPACTS: AIAA PLANETARY DEFENSE
CONFERENCE
American Institute of Aeronautics and
Astronautics, 16 December 2002
(2) "METEOR TRACKING IMPACT IS LARGE"
The Albuquerque Tribune, 16 December 2002
(3) STARS IN THEIR EYES: TUCSON AMATEUR ASTRONOMERS SCAN SKY FOR
ASTEROIDS
Tucson Citizen, 16 December 2002
(4) EXPLORING SPACE WILL REQUIRE NEW ROBOTS
Ledger-Enquirer, 16 December 2002
(5) PANSPERMIA VERIFIED? "MICROBES FROM EDGE OF SPACE
REVIDED"
New Scientist, 17 December 02
(6) NEW PREMISE IN SCIENCE: GET THE WORD OUT QUICKLY, ONLINE
The New York Times, 17 December 2002
(7) FORMATION OF ASTEROID FAMILIES BY CATASTROPHIC DISRUPTION
P. Michel et al.
(8) ESO LARGE PROGRAM ON PHYSICAL STUDIES OF TRANSNEPTUNIAN
OBJECTS AND
CENTAURS
H. Boehnhardt et al.
(9) CATACLYSMIC BOMBARDMENT THROUGHOUT THE INNER SOLAR SYSTEM
3.9-4.0 GA
D.A. Kring & B.A. Cohen
(10) ASTROPHYSICAL & ASTROCHEMICAL INSIGHTS INTO THE ORIGIN
OF LIFE
P. Ehrenfreund et al.
(11) AND FINALLY: SCIENTIFIC DESPERADOS PREDICT THE END OF
HUMANKIND IS NIGH
The Sunday Times, 15 December 2002
===========
(1) PROTECTING EARTH FROM NEO IMPACTS: PLANETARY DEFENSE
CONFERENCE 2003
>From American Institute of Aeronautics and Astronautics, 16
December 2002
http://biz.yahoo.com/prnews/021216/dcm049_1.html
The Aerospace Corporation to Chair AIAA's First Planetary Defense
Conference:
Protecting Earth From Asteroids
Monday December 16, 7:58 pm ET
EL SEGUNDO, Calif., Dec. 16 /PRNewswire/ -- In view of a
realistic threat
from Near Earth Objects (comets and asteroids), The Aerospace
Corporation
has joined with the American Institute of Aeronautics and
Astronautics to
address technical and policy issues relative to the defense of
Planet Earth.
A new forum, slated for February 2004: AIAA's 1st Planetary
Defense
Conference: Protecting Earth From Asteroids, will approach the
threat from
the perspective of three levels of warnings: 1) Short term (less
than 10
years warning of possible impact); 2) Medium term (10 to 30 years
warning);
and 3) Long term (more than 30 years warning), with an
overarching intent to
define several possible threat scenarios and develop potential
responses for
each.
Focused conference topics will:
* Examine current and
future detection capabilities and options
* Consider current and
future techniques, hardware and systems
available
to mitigate threats
* Discuss national and
international policy implications of mounting a
planetary
defense effort
* Develop
recommendations for future work, strategies, and policies
* Develop
recommendations for demonstrations/experiments/near-term
activities
* Discuss public
safety and disaster preparedness implications of
possible
asteroid or comet impacts
Dr. William Ailor of The Aerospace Corporation is General
Chairman of the
conference.
A Call for Papers is currently being issued, which will solicit
studies on
(1) the physical characteristics of the threat population (type,
size,
shape, velocity, trajectory, direction, frequency); (2) threat
detection and
warning (detection capabilities and methods, probability of
collision with
Earth, action thresholds); (3) mitigation techniques and
scenarios
(capabilities for diverting away from Earth -- imminent vs.
long-term threat
objects); (4) disaster preparedness (impact scenarios and
consequences,
public notification and coordination); (5) policy and planning
(political,
policy, regulatory and planning issues related to planetary
defense, and
minimum level of ongoing research to maintain readiness).
For the complete Call for Papers and more information, visit the
AIAA Web
site at http://www.aiaa.org/events/PDC04
===========
(2) "METEOR TRACKING IMPACT IS LARGE"
>From The Albuquerque Tribune, 16 December 2002
http://www.abqtrib.com/archives/news02/121602_news_meteor.shtml
By Sue Vorenberg
Tribune Reporter
Predicting when the next big meteor will hit the Earth is a
tricky business,
but scientists in New Mexico are making the process easier and
more
accurate.
After an 8-year study, scientists at Los Alamos and Sandia
national
laboratories have made a graph of the size and energy of meteors
and the
frequency at which they occur.
Even with that data, there is still a lot of work to be done
before anybody
will know how to stop them, said Doug ReVelle, a Los Alamos
researcher who
worked on the project.
"From an energy standpoint, the farther from Earth we find
these things, the
easier it will be to push them away and protect ourselves,"
ReVelle said.
"The real worry is the number of people around the world
trying to track
these things, and the information we have about them, is really
small. There
are probably about two dozen people working on this around the
globe -
that's a lot of space to cover."
A big problem with the lack of information is that most countries
have no
way to tell when a meteor has hit, or if it has hit at all. And
with recent
threats of military action, especially in the Middle East, that
can create
some worrisome problems, said Dick Spalding, a Sandia senior
engineer.
"We can see these things pretty well in the United
States," Spalding said.
"But the problem is other countries might mistake a large
meteor for
something else. In fact, it might be mistaken for a nuclear
detonation.
Suppose a large impact event occurs over India and Pakistan,
which has
happened before. If it had been big enough, since they couldn't
see where it
came from, certainly one country or another might feel they had
been
attacked and retaliate."
Destroying meteors and dispersing information about them is one
thing, but
scientists are still scrambling to see what types and sizes of
meteors are
hitting the Earth, what they're made of and where they're coming
from.
Lab scientists from New Mexico, working with astrophysicists from
the
University of Western Ontario in Canada and U.S. Space Command in
Colorado,
have made the first small steps in the effort to understand the
threat these
meteors pose.
They published their work - a graph of the size and frequency of
meteor
strikes - in a paper in the November issue of the journal Nature.
"The question of how frequently meteor strikes, or bolides,
occur, depends
on our ability to understand the amount of energy each one of the
events
has," ReVelle said. "The typical satellite optical
record gives you how much
light they emit, but until this study we weren't able to
determine how that
light was related to the size and energy of one of these
objects."
The scientists used sound waves lower than the human ear can hear
- called
infrasound - and coupled the information with satellites and
ground-based
telescopes. They cataloged detailed information about 300 strikes
during the
study, and through that information found a way to associate the
light
generated from an object and how much energy it has.
Through that information they were able to graph data from the
300 strikes.
They found the information matched up almost exactly with other
studies.
"The amazing thing is when you plot the results against
these other
techniques it lowers the rate at which these really huge objects
hit the
Earth," ReVelle said.
The last documented large event happened in northern Russia in
1908. The
event, called the Tanguska meteor, created a 10-megaton explosion
- about 70
times greater than the Hiroshima bomb - leveling forests for 40
miles in
every direction.
Scientists had previously predicted such events occurred every
150 to 300
years, but through the graph, they were able to recompute the
averages. They
now think such events occur about every 800 to 1,200 years,
ReVelle said.
Smaller, but still dangerous, one-megaton explosions, about seven
times
greater than the Hiroshima bomb, occur about every 100 years.
S.P. Worden, an Air Force brigadier general and astrophysics
Ph.D. who
worked on the project, testified before Congress this summer that
even
smaller meteor strikes could be mistaken for a missile by
countries that
don't have accurate identification technology.
He has been trying to get the government to create a full-time
office to
monitor meteor strikes and quickly disperse information to
countries to
prevent such retaliation, Spalding said.
"That's one of the things Gen. Worden is proposing right
now, and I think
he's got good reason to do so," Spalding said. "The
things we're seeing
range from ordinary strikes to events that appear very similar to
nuclear
explosions. Getting funding for an office like that is going to
be very
hard, though. Apparently there has been good sentiment in the
Senate, but I
haven't heard about any movement on that front."
Worden did not return The Tribune's phone calls despite several
requests to
the Air Force for an interview.
Even with the graph, a variety of other questions about meteors
remain,
ReVelle said.
"These meteors come in all different flavors - some are made
of iron or
nickel, some of carbon, some are comet material," ReVelle
said. "Techniques
for nudging an object away from the Earth would depend on the
object. Some
softer materials could actually break up when we try to move it
and end up
turning into buckshot."
It would probably cost between $5 million and $10 million a year
to improve
the work being done to understand meteors, but no country has
volunteered to
set up an office.
In the meantime, a lot of the work is done by scientists in their
spare
time, ReVelle said.
"I think the sad thing is what it would cost to really do
this job, compared
to what we're doing in other areas, is really nothing,"
ReVelle said. "I
find it ludicrous when you consider the consequences. Military
problems
aside, eventually the Earth is going to get hammered by a really
big event
that will do tremendous damage - kill people, bring down power
systems,
destroy homes or cities. This is a real problem somebody is going
to have to
deal with sooner or later."
© The Albuquerque Tribune.
==========
(3) STARS IN THEIR EYES: TUCSON AMATEUR ASTRONOMERS SCAN SKY FOR
ASTEROIDS
>From Tucson Citizen, 16 December 2002
http://www.tucsoncitizen.com/local/12_16_02astronomers.html
IRENE HSIAO
Roy Tucker stares into the icy heart of the universe most nights
- via a
computer in his cozy West Side home. Unless clouds interfere,
Tucker starts
his evenings by cranking up five computers that control four
telescopes in
his back yard. He walks out back, opens the roof of an
8-by-12-foot homemade
structure, exposing the 14-inch telescopes. Then he takes the lid
off
another telescope that sits in a nearby dome and pets his dog,
Bear, before
going back inside to sit at the computers.
Tucker is among a growing group of advanced amateur astronomers
worldwide
who aid professional astronomers in their research. "I
thought it would be
fun to give them some friendly competition," said Tucker,
who has been
monitoring the skies regularly for about six years.
Tucker, who by day is a senior engineer at the University of
Arizona's
Steward Observatory, hunts mostly for near-Earth objects -
asteroids or
comets.
About 11 p.m. he usually performs one final chore.
With a click of a mouse, he sends his observations to the Minor
Planet
Center at the Smithsonian Astrophysical Observatory in Cambridge,
Mass. The
non-profit organization, run by the International Astronomical
Union, tracks
the orbits of asteroids and comets.
Most of the Minor Planet Center's observers are amateurs - just
20 percent
are professionals, including members of research programs at UA
and the Jet
Propulsion Laboratory in Pasadena, Calif. Tucker, 50, is one of
about 100
amateur observers who deliver data to the Minor Planet Center,
and he is
part of Tucson's handful of amateur astronomers who feed free
information to
professionals.
"Roy surveys the skies and gets lots of different objects
that we then try
to identify," said Brian Marsden, director of the Minor
Planet Center. "He's
almost like Space Watch himself."
The University of Arizona's Space Watch program provides the
center with
several hundred observations per day.
Tucker says it's become more difficult to discover asteroids
since he
started tracking them in 1996, when less than 10,000 had been
chronicled.
"Back then discovering asteroids was like frolicking through
the meadows and
picking daisies," said Tucker, who has discovered 160
asteroids and one
comet.
Increasingly affordable equipment and the global reach of the
Internet are
behind the rise of sophisticated amateur astronomers.
The charged-coupled device, or CCD, revolutionized the
capabilities of
amateur astronomers, said Leif Robinson, former editor of Sky and
Telescope
magazine. CCDs, developed in the 1980s, are chips that allow
astronomers to
transfer images of celestial objects electronically.
Technological
improvements in the past five years such as more affordable
digital cameras
also have spurred the growth in research by amateur astronomers.
"Amateurs have incredible access to equipment very similar
to
professionals," says Jim Bell, an astronomy professor at
Cornell University.
"Telescope makers are trying to target these folks now. In
some cases they
are willing to spend a substantial amount of money."
Bell describes the amount of money amateur astronomers are
spending on
telescopes and other equipment this way: "Hey, honey, let's
not buy a car,
let's buy a telescope next year."
Tucker made his first CCD camera in 1993 and bought some of the
components
from a line of parts that were initially developed for the
Galileo space
mission.
He now has put together eight of the cameras, spending about
$1,200 on parts
for each one.
The most famous local amateur astronomer is David Levy, who has
discovered
21 comets - eight by himself and 13 that he co-discovered with
Gene and
Carolyn Shoemaker. One of the comets, Shoemaker-Levy 9, collided
with
Jupiter in the summer of 1994, resulting in the greatest
explosion ever
witnessed on another world, according to Levy's Web site.
Robinson estimates there are half a million amateur astronomers
in the
United States, including thousands who are engaged in research
ranging from
a "simple guesstimating of star brightness to discovering a
new spot on
Jupiter."
"There's no way the (5,000) to 6,000 (professionals) in the
United States
can look at everything," Robinson said. "You just have
a larger cadre of
people scanning the sky."
Astronomy has long benefited from the involvement of amateurs.
Nicholas
Copernicus, who had many interests besides astronomy, determined
in 1543
that the sun, not the Earth, was at the center of the solar
system.
Edmond Halley, who predicted the return of the comet that would
bear his
name, was an amateur, and Johannes Kepler, who made a living
through
teaching and publishing books, discovered that planets orbit in
ellipses,
not circles.
"Astronomy sees more serious amateur activity than in any
other science,"
Marsden said.
James McGaha, 56, another Tucson amateur astronomer, lives near
Sabino
Canyon on the Northeast Side. He searches the night skies for
supernovas in
galaxies outside the Milky Way and for asteroids. McGaha has
discovered 15
asteroids but no supernovas.
"I have come close, but no bananas," he said.
The retired U.S. Air Force pilot has taught astronomy as an
adjunct
instructor at Pima Community College. He has a master's degree in
astronomy
from the University of Arizona, but has never been a professional
astronomer.
McGaha has an observatory with a 12-inch telescope in his back
yard and uses
a 24-inch telescope near Sonoita that he operates with another
amateur.
McGaha conducts "follow-up research" that he e-mails to
the Minor Planetary
Center between 3 and 4 a.m.
Once a professional astronomer has listed on the Internet an
asteroid that
may be coming close to Earth, McGaha will generally monitor the
asteroid the
next night.
McGaha's contribution is significant, said the Minor Planet
Center's
Marsden, because it can help verify the existence of an object
that could
potentially hit Earth.
"I very much value what James McGaha does," Marsden
said.
Tucker, who received his first telescope as a Christmas present
when he was
15, said he has no regrets about not turning professional.
"I guess I've never lost the excitement of astronomy,"
he said. "If you do
astronomy as a professional, you lose some of that."
Copyright © 2002 Tucson Citizen
=========
(4) EXPLORING SPACE WILL REQUIRE NEW ROBOTS
>From Ledger-Enquirer, 16 December 2002
http://www.ledger-enquirer.com/mld/ledgerenquirer/news/4750884.htm
BY CAROLE RUTLAND
Oh the places we will go!
Disguised as futuristic ants, newly designed artificial
intelligence will be
able to venture into the nooks and crannies of space as never
before
possible.
They're tiny and weigh in at about 2.2 pounds, but they could fan
among the
hundreds of thousands of asteroids and begin to explore.
They're called ANTS -- it's an acronym for Autonomous Nano
Technology Swarm,
a fleet of tiny insect-like spacecraft which could cruise all by
themselves
to the asteroid belt. Equipped with mini solar sails, each
high-tech critter
would use the delicate pressure of the sun's rays to push it
along on its
journey.
The ANTS could provide a hands-on survey of the asteroid belt to
determine
which individual rocks had the greatest potential to generate the
mother
lode. They would provide a guide to the most important and
predominant
mineral resources for the future.
The ANTS mission would not launch before 2020 at the earliest,
and once
we're there it will be necessary to use something called
Lagrangian orbits,
or L-points, if we are to park our probes for any length of time
in space.
These invisible orbits are points where the gravitational
attractions of two
celestial bodies are in perfect balance. That means that a
particle of
negligible mass could remain in equilibrium.
For example, between the Earth and moon there are five such
points, as there
would be between any two bodies in circular orbits about each
other. These
points are designated L1 through L5.
Scientists refer to these points as invisible planets, large
amounts of
space where one can stop and hang out for a while without using
great
amounts of energy. The view is wonderful, with no atmosphere to
interfere.
The swarm would take three or more years to travel to the main
belt of
asteroids. Once there, about 100 chief administrators and middle
management
ANTS would consult while looking on and guiding operations.
In the meantime, some 900 or so staff assistant ANTS robots do
the bulk of
the work. Only a small number of the chief administrator probes
would then
make the return trip to their space-based safe harbor at the
L-point,
ferrying with them the precious information acquired during the
mission.
Scientists dream of creating colonies of insect-like robots,
which not only
move like but also think like their biological counterparts. They
would
divide responsibilities and roles much like the colonies of ants
or bees
found in your backyard.
In the case of the ANTS proposal, the probes would perform their
tasks
individually, but they would also swap what they've learned back
and forth
so the colony would behave as a single unit or network, as would
a single,
larger spacecraft.
Exploration of space began hundreds of years ago, when we looked
through a
tiny telescope and learned that we were not at the center of the
universe as
previously believed.
Years pass and we explore with larger telescopes that look much
deeper into
the universe through eyes that can image infrared, X-rays and
gamma rays. We
send spacecraft out to investigate objects in our own backyard --
the
planets of our solar system.
And now we want to send investigative robots for a more in-depth
study of
these planets. Their permanent presence would give us geological
information
and a more realistic look at the processes necessary to move into
the next
era of exploration, when the human expansion into the solar
system begins in
earnest.
----------------------------------------------------------------------------
----
Carole Rutland is executive director of the Columbus State
University
Coca-Cola Space Science Center.
Copyright 2002, Ledger-Enquirer
===============
(5) PANSPERMIA VERIFIED? "MICROBES FROM EDGE OF SPACE
REVIDED"
>From New Scientist, 17 December 02
http://www.newscientist.com/news/news.jsp?id=ns99993186
Microbes collected from the edge of space have been brought back
to life in
the lab.
This enabled the high-flying organisms to be identified, almost
two years
after they were found in air samples collected by a weather
balloon cruising
at 41,000 metres (135,000 feet) over southern India.
The two species of bacteria (B. simplex, S. pasteuri) and one
fungus (E.
albus) are similar to common ground-dwelling microbes which lurk
in soil and
vegetation, says Milton Wainwright of the University of
Sheffield, UK, who
worked out how to culture the cells.
How the bugs got there is not known, but there are three
possibilities: they
were carried up on winds, they sneaked into the samples on Earth
or they
have flown through space and are aliens making their way down to
our planet.
The latter possibility fits with a theory developed by Chandra
Wickramasinghe and the late Fred Hoyle in the 1970s, which
proposes that
life originated elsewhere in the Universe and hitched a lift to
Earth on a
passing comet.
Wickramasinghe, at the Cardiff University Centre for Astrobiology
in Wales,
is Wainwright's co-author on the new paper, along with the Indian
scientists
that sent up the balloon. If the microbes were indeed drifting in
from
space, Wickramasinghe calculates that up to a tonne could be
landing each
year, based on the density of microbes found in the air samples.
Up draught
Wainwright admits that the simplest explanation is that the
organisms, found
above 99 per cent of the Earth's atmosphere, have terrestrial
origins. But,
he asks, how did they get up there?
Turbulent winds at ground level are certainly capable of sweeping
particles
up into the atmosphere. But this kind of weather is confined
beneath the
tropopause, which acts like a lid at about 17,000 metres.
Volcanic eruptions can push matter through the tropopause. But
there were no
such events in the months before the samples were taken, and
gravity would
be expected to drag any microbes back down in a few days.
However, the man-made greenhouse gases called CFCs have been
found at
similar altitudes, showing that global air currents can pierce
the
tropopause. Martin Juckes, an atmospheric scientist at the
Rutherford
Appleton Laboratory, UK, says that air flows upwards at the
tropics at about
one metre per hour, and may carry material with it. But whether
particles as
large as microbes could be carried to such heights is not known.
Freeze-dried
The third possibility, that the microbes represent experimental
contamination, is dismissed by Wainwright. The experimental
protocol was
carefully designed to exclude contamination before the samples
were
collected during the balloon flight (New Scientist print edition,
4 August
2001).
And contamination after the samples had been returned to Earth is
unlikely,
he argues, because the microbes were freeze-dried. This was due
to the cold,
dry conditions at 41,000 metres, he says.
To coax them into growing, Wainwright had to soak them in a
nutrient
solution. They refused to multiply when spread on the jellies
usually used
to culture samples - but any contaminant cells would have shown
up at this
stage, he says.
Journal Reference: FEMS Microbiology Letters) (Article 10778)
Jenny Hogan
Copyright 2002, New Scientist
=============
(6) NEW PREMISE IN SCIENCE: GET THE WORD OUT QUICKLY, ONLINE
>From The New York Times, 17 December 2002
http://www.nytimes.com/2002/12/17/science/17JOUR.html
By AMY HARMON
A group of prominent scientists is mounting an electronic
challenge to the
leading scientific journals, accusing them of holding back the
progress of
science by restricting online access to their articles so they
can reap
higher profits.
Supported by a $9 million grant from the Gordon and Betty Moore
Foundation,
the scientists say that this week they will announce the creation
of two
peer-reviewed online journals on biology and medicine, with the
goal of
cornering the best scientific papers and immediately depositing
them in the
public domain.
By providing a highly visible alternative to what they view as an
outmoded
system of distributing information, the founders hope science
itself will be
transformed. The two journals are the first of what they envision
as a vast
electronic library in which no one has to pay dues or seek
permission to
read, copy or use the collective product of the world's academic
research.
"The written record is the lifeblood of science," said
Dr. Harold E. Varmus,
a Nobel laureate in medicine who is serving as the chairman of
the new
nonprofit publisher. "Our ability to build on the old to
discover the new is
all based on the way we disseminate our results."
By contrast, established journals like Science and Nature charge
steep
annual subscription fees and bar access to their online editions
to
nonsubscribers, although Science recently began providing free
electronic
access to articles a year after publication.
The new publishing venture, Public Library of Science, is an
outgrowth of
several years of friction between scientists and the journals
over who
should control access to scientific literature in the electronic
age. For
most scientists, who typically assign their copyright to the
journals for no
compensation, the main goal is to distribute their work as widely
as
possible.
Academic publishers argue that if they made the articles more
widely
available they would lose the subscription revenue they need to
ensure the
quality of the editorial process. Far from holding back science,
they say,
the journals have played a crucial role in its advancement as a
trusted
repository of significant discovery.
"We have very high standards, and it is somewhat
costly," said Dr. Donald
Kennedy, the editor of Science. "We're dealing in a market
whether we like
it or not."
Science estimates that 800,000 people read the magazine
electronically now,
compared with 140,000 readers of the print version. Given the
number of
downloads at universities like Harvard and Stanford, which buy
site licenses
for about $5,000 a year, the magazine says people are reading
articles for
only a few cents each.
In many cases even such small per-article charges to access a
digital
database can make for substantial income. The Dutch-British
conglomerate
Reed Elsevier Group, the world's largest academic publisher,
posted a 30
percent profit last year on its science publishing activities.
Science took
in $34 million last year on advertising alone.
But supporters of the Public Library of Science say the point is
not how
much money the journals make, but their monopoly control over
literature
that should belong to the public.
"We would be perfectly happy for them to have huge profit
margins providing
that in exchange for all this money we're giving them we got to
own the
literature and the literature did not belong to them," said
Dr. Michael B.
Eisen, a biologist at Lawrence Berkeley National Laboratory and
the
University of California, and a founder of the Public Library of
Science.
When scientists relied on print-and-paper journals to distribute
their work,
the Library's supporters argue, it made sense to charge for
access, since
each copy represented an additional expense. But they say that at
a time
when the Internet has reduced distribution costs to almost zero,
a system
that grants journals exclusive rights over distribution is no
longer
necessary.
By publishing on the Internet and forgoing any profits, the new
venture says
it is now possible to maintain a high-quality journal without
charging
subscription fees.
FULL ARTICLE AT http://www.nytimes.com/2002/12/17/science/17JOUR.html
==============
(7) FORMATION OF ASTEROID FAMILIES BY CATASTROPHIC DISRUPTION
Michel P, Tanga P, Benz W, Richardson DC: Formation of asteroid
families by
catastrophic disruption: Simulations with fragmentation and
gravitational
reaccumulation
ICARUS 160 (1): 10-23 NOV 2002
This paper builds on preliminary work in which numerical
simulations of the
collisional disruption of large asteroids (represented by the
Eunomia and
Koronis family parent bodies) were performed and which accounted
not only
for the fragmentation of the solid body through crack
propagation, but also
for the mutual gravitational interaction of the resulting
fragments. It was
found that the parent body is first completely shattered at the
end of the
fragmentation phase, and then subsequent gravitational
reaccumulations lead
to the formation of an entire family of large and small objects
with
dynamical properties similar to those of the parent body. In this
work, we
present new and improved numerical simulations in detail. As
before, we use
the same numerical procedure, i.e., a 3D SPH hydrocode to compute
the
fragmentation phase and the parallel N-body code pkdgrav to
compute the
subsequent gravitational reaccumulation phase. However, this
reaccumulation
phase is now treated more realistically by using a merging
criterion based
on energy and angular momentum and by allowing dissipation to
occur during
fragment collisions. We also extend our previous studies to the
as yet
unexplored intermediate impact energy regime (represented by the
Flora
family formation) for which the largest fragment's mass is about
half that
of the parent body. Finally, we examine the robustness of the
results by
changing various assumptions, the numerical resolution, and
different
numerical parameters. We find that in the lowest impact energy
regime the
more realistic physical approach of reaccumulation leads to
results that are
statistically identical to those obtained with our previous
simplistic
approach. Some quantitative changes arise only as the impact
energy
increases such that higher relative velocities are reached during
fragment
collisions, but they do not modify the global outcome
qualitatively. As a
consequence, these new simulations confirm previous main results
and still
lead to the conclusion that: (1) all large family members must be
made of
gravitationally reaccumulated fragments; (2) the original
fragment size
distribution and their orbital dispersion are respectively
steeper and
smaller than currently observed for the real families, supporting
recent
studies on subsequent evolution and diffusion of family members;
and (3) the
formation of satellites around family members is a frequent and
natural
outcome of collisional processes. (C) 2002 Elsevier Science
(USA).
Addresses:
Michel P, Observ Cote Azur, BP 4229, F-06304 Nice 4, France
Observ Cote Azur, F-06304 Nice 4, France
Univ Bern, Inst Phys, CH-3012 Bern, Switzerland
Univ Maryland, Dept Astron, College Pk, MD 20742 USA
Copyright © 2002 Institute for Scientific Information
============
(8) ESO LARGE PROGRAM ON PHYSICAL STUDIES OF TRANSNEPTUNIAN
OBJECTS AND
CENTAURS
Boehnhardt H, Delsanti A, Barucci A, Hainaut O, Doressoundiram A,
Lazzarin
M, Barrera L, de Bergh C, Birkle K, Dotto E, Meech K, Ortiz JE,
Romon J,
Sekiguchi T, Thomas N, Tozzi GP, Watanabe J, West RM: ESO large
program on
physical studies of Transneptunian Objects and Centaurs: Visible
photometry
- First results
ASTRONOMY & ASTROPHYSICS 395 (1): 297-303 NOV 2002
We present the first results of BVRI photometry of Transneptunian
Objects
(TNOs) and Centaurs obtained through the ESO Large Program on
physical
studies of these icy bodies in the outer solar system. In total
28 objects
were observed of which 18 are new measurements. Combining our new
BVRI
photometry with the data summary published by Hainaut &
Delsanti (2002)
results in a database of 94 objects: 45 Cubewanos, 22 Plutinos,
13 scattered
disk objects, 14 Centaurs. The reddening range seems to be
similar among the
four dynamical classes (-5 to 55%/100 nm) and only one outlier
(1994 ES2)
exists. The spectral gradient distribution of the Cubewanos peaks
between 25
to 35%/100 nm, while for the three other types the maximum seems
to fall
below 20%/100 nm. A clustering of red Cubewanos with perihelia
beyond
similar to41 AU in low eccentricity and low inclination orbit
suggests that
these objects are less affected by the physical processes that
potentially
produce neutral colors, i.e. resurfacing by collision and by
intrinsic
activity. For Cubewanos and scattered disk objects, the range of
reddening
increases with decreasing perihelion distance and with increasing
orbital
excitation. A correlation of the spectral slope with inclination
is present
for Cubewanos and scattered disk objects, and is non-existent for
the other
dynamical types. It is unclear whether these trends (or their
absence) are
discriminative for the correctness of the resurfacing scenarios.
If
intrinsic activity is responsible for resurfacing, the start of
the effect
inside similar to41 AU from the Sun may be indicative for the
driving agent,
while in the collision scenario the survival of the red Cubewano
cluster in
the central region of the Kuiper-Belt argues for the existence of
a
population of bodies the surface of which is heavily radiation
processed
without impact resurfacing.
Addresses:
Boehnhardt H, European So Observ, Alonso de Cordova 3107,
Santiago, Chile
European So Observ, Santiago, Chile
Observ Paris, F-92195 Meudon, France
Astron Observ Padova, I-35122 Padua, Italy
Univ Catolica Norte, Inst Astron, Antofagasta, Chile
Max Planck Inst Astron, D-69117 Heidelberg, Germany
Osserv Astron Torino, INAF, I-10025 Pino Torinese, TO, Italy
Osserv Astron Roma, INAF, I-00040 Rome, Italy
Univ Hawaii, Honolulu, HI 96822 USA
Inst Astron Andalucia, Granada 18080, Spain
Natl Astron Observ, Tokyo 181, Japan
Max Planck Inst Aeron, D-37189 Katlenburg Lindau, Germany
Osserv Astrofis Arcetri, I-50125 Florence, Italy
European So Observ, D-85748 Garching, Germany
Copyright © 2002 Institute for Scientific Information
=============
(9) CATACLYSMIC BOMBARDMENT THROUGHOUT THE INNER SOLAR SYSTEM
3.9-4.0 GA
Kring DA, Cohen BA
JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS 107 (E2): art. no. 5009
FEB 25 2002
[1] Cohen et al. [2000] recently confirmed the hypothesis that
the Moon was
resurfaced by an intense period of impact cratering similar to3.9
Ga ago
and, by inference, that the Earth also sustained bombardment.
Analyses of
lunar impact melts indicate that at least one of the projectiles
that hit
the Moon was a differentiated iron-rich core, implying the
bombardment was
caused by asteroids. Meteorite analyses indicate asteroids in the
asteroid
belt were also heavily cratered similar to3.9 Ga and that the
ancient
cratered highlands of Mars suffered impacts at this time.
Collectively,
these data suggest there was an impact cataclysm that affected
the entire
inner solar system, resurfacing the terrestrial planets, and that
the source
of the impacting debris was the asteroid belt. Comets do not
appear to have
been important.
Addresses:
Kring DA, Univ Arizona, Lunar & Planetary Lab, 1629 E Univ
Blvd, Tucson, AZ
85721 USA
Univ Arizona, Lunar & Planetary Lab, Tucson, AZ 85721 USA
Univ Tennessee, Dept Geol Sci, Knoxville, TN 37996 USA
Copyright © 2002 Institute for Scientific Information
============
(10) ASTROPHYSICAL & ASTROCHEMICAL INSIGHTS INTO THE ORIGIN
OF LIFE
Ehrenfreund P, Irvine W, Becker L, Blank J, Brucato JR, Colangeli
L, Derenne
S, Despois D, Dutrey A, Fraaije H, Lazcano A, Owen T, Robert F
REPORTS ON PROGRESS IN PHYSICS 65 (10): 1427-1487 OCT 2002
Stellar nucleosynthesis of heavy elements such as carbon allowed
the
formation of organic molecules in space, which appear to be
widespread in
our Galaxy. The physical and chemical conditions-including
density,
temperature, ultraviolet (UV) radiation and energetic
particles-determine
reaction pathways and the complexity of organic molecules in
different space
environments. Dense interstellar clouds are the birth sites of
stars of all
masses and their planetary systems. During the protostellar
collapse,
interstellar organic molecules in gaseous and solid phases-are
integrated
into protostellar disks from which planets and smaller solar
system bodies
form. After the formation of the planets 4.6 billion years ago,
our solar
system, including the Earth, was subjected to frequent impacts
for several
hundred million years. Life on Earth may have emerged during or
shortly
after this heavy bombardment phase, perhaps as early as 3.90-3.85
billion
years ago, but the exact timing remains uncertain. A prebiotic
reducing
atmosphere, if present, predicts that building blocks of
biopolymers-such as
amino acids, sugars, purines and pyrimidines-would be formed in
abundance.
Recent modelling of the Earth's early atmosphere suggests, in
contrast, more
neutral conditions (e.g. H2O, N-2, CO2), thus, precluding the
formation of
significant concentrations of prebiotic organic compounds.
Moreover, even if
the Earth's atmosphere were reducing, the presence of UV photons
would
readily destroy organic compounds unless they were quickly
sequestered away
in rocks or in the prebiotic ocean. Other possible sources of
organic
compounds would be high temperature vent chemistry, although the
stability
of such compounds (bases, amino acids) in these environments
remains
problematic. Finally, organic compounds may have been delivered
to the Earth
by asteroids, comets and smaller fragments, such as meteorites
and
interplanetary dust particles.
It is likely that a combination of these sources contributed to
the building
blocks of life on the early Earth. It may even have taken several
starts
before life surpassed the less than ideal conditions at the
surface. What is
certain is that once life emerged, it learned to adapt quickly
taking
advantage of every available refuge and energy source (e.g.
photosynthesis
and chemosynthesis), an attribute that eventually led to complex
metabolic
life and even. our own existence.
Current experimental research investigating the origin of life is
focused on
the spontaneous formation of stable polymers out of monomers.
However,
understanding the spontaneous formation of structure is not
enough to
understand the formation of life. The introduction and evolution
of
information and complexity is essential to our definition of
life. The
formation of complexity and the means to distribute and store
information
are currently being investigated in a number of theoretical
frameworks, such
as evolving algorithms, chaos theory and modem evolution theory.
In this paper we review the physical and chemical processes that
form and
process organic matter in space. In particular we discuss the
chemical
pathways of organic matter in the interstellar medium, its
evolution in
protoplanetary disks and its integration into solar system
material.
Furthermore, we investigate the role of impacts and the delivery
of organic
matter to the prebiotic Earth. Processes that may have assembled
prebiotic
molecules to produce the first genetic material and ideas about
the
formation of complexity in chemical networks are also discussed.
Addresses:
Ehrenfreund P, Leiden Observ, POB 9513, NL-2300 RA Leiden,
Netherlands
Leiden Observ, NL-2300 RA Leiden, Netherlands
Leiden Univ, Leiden Inst Chem, Soft Matter Astrobiol Lab, NL-2300
RA Leiden,
Netherlands
Univ Massachusetts, Dept Astron, Lederle Grad Res Ctr 619,
Amherst, MA 01003
USA
Univ Calif Santa Barbara, Inst Crystal Studies, Dept Geol Sci,
Santa
Barbara, CA 93106 USA
Lawrence Livermore Natl Lab, H Div, Shock Phys Grp, Livermore, CA
94551 USA
Osserv Astron Capodimonte, INAF, I-80131 Naples, Italy
Ecole Natl Super Chim Paris, CNRS, UMR 7573, Lab Chim Bioorgan
& Organ Phys,
F-75231 Paris 05, France
Observ Aquitain Sci Univers OASO, F-33270 Florac, France
Observ Grenoble, LAOG, Astrophys Lab, F-38041 Grenoble 9, France
Univ Nacl Autonoma Mexico, Fac Ciencias, Mexico City 04510, DF,
Mexico
Univ Hawaii, Inst Astron, Honolulu, HI 96822 USA
Museum Natl Hist Nat, Lab Mineral, F-75005 Paris, France
Copyright © 2002 Institute for Scientific Information
===========
(11) AND FINALLY: SCIENTIFIC DESPERADOS PREDICT THE END OF
HUMANKIND IS NIGH
>From The Sunday Times, 15 December 2002
http://www.timesonline.co.uk/article/0,,2099-505027,00.html
COUNTDOWN TO CATASTROPHE
It is set to be the great debate of 2003. Fifty years after the
discovery of
DNA, even as we unlock the secrets of life, humanity is on the
verge of
being snuffed out. Serious scientific voices are raising concerns
that this
world may not survive the new century. We are threatened from
without and
from within - by forces beyond our control, and by those we have
engineered
and which may yet come to control us Bryan Appleyard reveals the
10 main
threats to life on Earth
To be brutally frank, we're not going to make it. The human race
is doomed,
either through what insurers coyly describe as an 'act of God' or
through
our own stupidity. Earth, we know for sure, will be destroyed in
5 billion
years when the sun turns into a red giant and engulfs the inner
planets of
the solar system. But don't console yourself with the idea that,
by then, we
shall have happily colonised some other corner of the galaxy:
human survival
even into the 22nd century is already looking like a long shot.
In his forthcoming book, Our Final Century, the British
cosmologist Sir
Martin Rees rates our chances as no better than 50-50. Bill Joy,
the founder
of Sun Microsystems and one of the leading technocrats of our
time, thinks
machines will soon usurp the human race. Others think
nanotechnology - the
construction of molecular-sized machines - will reduce the
Earth's surface
to a featureless goo. Genetically engineering viruses or bacteria
may have
the same effect. Meanwhile, we are overdue for a super-volcanic
eruption -
the most recent was 74,000 years ago - or an asteroid or comet
impact like
the one that wiped out the dinosaurs 65m years ago. Then there's
global
warming. And don't get me started on the impending vacuum
metastability
disaster.The good news is you can make money out of this. William
Hill
offered me absurd odds of 1m to 1 against the end of the world by
2200,
based on the assumption, as one William Hill spokesman said, that
'bookmakers will go to heaven - albeit temporarily - to pay those
punters
who have bet on the end of the world'. I told them Rees's odds,
but they
were unmoved on the basis that he and his publishers would say
that,
wouldn't they?
But the bookies are wrong. The threats to our survival are
numerous and
imminent. There are two categories of catastrophe to be
considered: the end
of the world (killing all humans and perhaps destroying the
planet), and the
end of the world as we know it (a disaster large enough to
transform human
civilisation, killing millions if not billions, but leaving
survivors). Both
scenarios can be caused by nature or by humanity.
And why is this suddenly an issue? The answer is knowledge. We
now
understand that the human race has prospered in a period of
unusual cosmic
and geological calm. We know that the issue is not if some awful
natural
disaster will happen, but when. And our knowledge has brought us
to a
technological brink: we have the means to destroy the world. 'If
hamadryas
baboons had nuclear weapons, they would destroy the world in a
week,' said
the great biologist E O Wilson. But just a few fragments of DNA
separate us
from baboons. Furthermore, when the Americans tested the first
atom bomb in
1945, some scientists believed the test would set the atmosphere
on fire or
start a catastrophic chain reaction in the hydrogen locked up in
the oceans.
But they went ahead and did it on that well-known principle of
modern
physics: 'What the hell, let's give it a whirl.'Here, then, are
the top-10
terrible things that might happen. The only question is whether
they will
finish us off completely, or just knock us back. We are 6 billion
ill-tempered neurotics clinging to a rock in an utterly
indifferent, violent
universe. Never has the fragility of our existence been more
apparent. That
thought alone might be of some hope. The first images of Earth
from space
fired the environmental movement with the vision of a species
that trod more
lightly on our delicate planet. New awareness of how easily we
might be
extinguished by our own or nature's actions might lead us to draw
back from
more obvious dangers. But it might not. Life on Earth will then
turn out to
have been a temporary anomaly, a pale flicker, a brief cry in the
darkness
and silence, seen and heard only by God.
FULL CATALOGUE OF END-TIME PROPHECIES AT
http://www.timesonline.co.uk/article/0,,2099-505027,00.html
MODERATOR'S NOTE: CCNet subscribers are reminded that cultural
pessimism and
secular apocalypticism is a 20th century European ailment that -
thank
goodness - is not shared universally. For a much optimistic
outlook to the
21st century, see
MASTERS OF THE UNIVERSE
http://reason.com/9801/bk.silber.shtml
By Kenneth Silber
Visions: How Science Will Revolutionize the 21st Century, by
Michio Kaku,
New York: Anchor Books/Doubleday, 403 pages, $24.95
Visions begins on a note of arrogance. Unlike previous efforts to
chart the
future of technology, Michio Kaku assures us, his predictions are
likely to
be correct. As science approaches a full understanding of the
laws of
nature, a scientific consensus is emerging about where technology
is headed
and on what timetable. This book, Kaku asserts, reflects that
consensus.
Baloney. What is remarkable about many of the advanced
technologies Kaku
discusses--artificial intelligence, genetic engineering, nuclear
fusion,
electric cars--is the distinct lack of scientific unanimity about
their
potential. For every physicist who says that fusion is "the
energy of the
future," there's another who replies, "Yes--and it
always will be." Even
when the experts are in general agreement--as they once were
about the
infeasibility of cloning an adult sheep--consensus has hardly
proven a
guarantee of predictive accuracy.
Nonetheless, Kaku, a theoretical physicist and high-profile
popularizer of
science, has written an absorbing book, filled with thoughtful
speculations
about the 21st century and beyond. Visions sketches what might
emerge from
three 20th-century scientific upheavals: the "computer
revolution," the
"bio-molecular revolution," and the "quantum
revolution." These revolutions
are interconnected, as Kaku notes; discovery of the DNA double
helix, for
example, relied on X-ray crystallography, a technique derived
from quantum
physics. Such linkages, he expects, will take on growing
importance in the
next century, in the form of DNA-based computers and other hybrid
technologies.
Visions provides an intriguing (and explicit) rejoinder to The
End of
Science, the 1996 book in which journalist John Horgan argued
that the era
of scientific discovery is sputtering out in disappointment and
confusion.
Similar to Horgan (but unlike eminent scientists such as Roger
Penrose and
Freeman Dyson), Kaku believes that breakthrough insights into
nature's
workings, such as evolution and relativity, are now mainly things
of the
past. But where Horgan detected intellectual drift and
technological
stagnation, Kaku sees something very different: The age of
discovery is
giving way to the age of mastery. Having learned the universe's
rules,
humans are finally ready to become full-fledged players in the
game.
The quantum, biomolecular, and computer revolutions, in other
words, are
enabling us to be "choreographers of matter, life, and
intelligence," no
longer mere passive observers of nature's dance. Yet even while
taking this
expansive view of technology's potential, Kaku is adept at
recognizing
technological hurdles and limits.
Computing power, Kaku expects, will become increasingly cheap and
ubiquitous
in the next two decades, manifested in such products as wearable
computers,
smart cars, and digital scrap paper. Helpful (but sometimes
annoying)
"intelligent agents" will sort your e-mail, update your
schedule, and remind
you to watch your diet. But before long, Kaku notes, chip making
will bump
up against the physical limits of silicon, and further progress
will depend
on the development of holographic memory, organic processors,
quantum
transistors, and other exotic technologies.
After 2020, Kaku predicts, the first glimmerings of true
artificial
intelligence will appear, as computers acquire common sense and
as the
Internet evolves into something similar to the "magic
mirror" that imparts
wisdom in fairy tales. After 2050, robots endowed with some
degree of
consciousness and self-awareness may roam the earth. Might
humanity
eventually be enslaved or slaughtered by its robotic creations?
Kaku closes
his discussion of artificial intelligence with an overview of the
built-in
safeguards that should be devised to prevent such an outcome.
Biotechnology also will make vast strides in the early 21st
century,
according to Kaku. By 2020, the genetic underpinnings of many
hereditary
diseases will be understood, and entire classes of cancer will be
curable.
People will own CD-ROMs containing their own personal DNA codes.
Between
2020 and 2050, genetic research will see slower progress, as
scientists
grapple with the intricacies of gene function and protein
folding. During
this period, however, it will become possible to grow new vital
organs in
the lab, perhaps extending the human life span by decades.
After the century's midpoint, Kaku writes, "we may be able
to manipulate
life itself." Yet he is impenetra-bly vague about what this
means. More
interesting is Kaku's discussion of feats that probably lie
beyond biotech's
reach. Performing major design changes on human beings--say,
growing wings
on a person's back, in Kaku's whimsical example--is unlikely to
be feasible
even in the late 21st century. Consider the obstacles involved:
The genes
that initiate wing formation in a bird or insect may do nothing
in a human
(or may activate homologous organs, such as arms); these genes
would have to
be altered to allow a wingspan of some 20 feet; and the human's
entire
genome would have to be transformed to create the lighter bones
and stronger
muscles required for flight.
Surveying the "quantum future," Kaku assesses a broad
range of possibilities
for manipulating matter and developing new sources of energy.
Electric cars
and magnetic-levitation trains are emerging as viable forms of
transportation, he argues, and solar power is poised to become a
leading
energy source. Room-temperature superconductors and microscopic
lasers may
find numerous industrial applications. Nanotechnology's
molecule-sized
machines are of uncertain feasibility, Kaku notes, but dust-sized
sensors
and motors will be used widely in the coming decades. Some other
staples of
science fiction, such as force fields and portable ray guns,
appear to be
incompatible with known laws of physics, he adds.
Space technology will make steady, if unspectacular, progress in
the next
few decades, according to Visions. Kaku is dismissive of the
notion of a
manned mission to Mars in the early 21st century, basing his
argument on
exorbitant cost estimates now widely regarded as erroneous. Yet
after 2020,
he emphasizes, astronomical instruments may be sensitive enough
to detect
Earth-like planets in other solar systems. The century's latter
half may see
ambitious efforts to develop fusion-powered interstellar rocket
ships.
Antimatter engines loom as an intriguing prospect sometime beyond
2100.
Kaku's social and political asides are less imaginative than his
technological speculations. He argues, plausibly but predictably,
that the
economic strength of nations in the 21st century will depend on
their
technological prowess. In chapters devoted to "second
thoughts," he presents
grim scenarios of "information ghettos" and
bioengineered germ weapons; his
solutions are unremarkable generalities about education and
international
cooperation. Some of Kaku's political pronouncements are mere
clichés.
Discussing the nation-state's future, he writes, "As John
Lennon said in his
song `Imagine,' perhaps it's not hard to imagine a world without
nations."
Might a public backlash against technology derail much of the
progress
forecast in this book? The history of advanced technologies in
the 20th
century--nuclear energy comes to mind--indicates that not
everything that is
technically feasible will end up receiving political and social
acceptance.
Certainly, the 21st century's "choreographers of matter,
life, and
intelligence" will face their share of protest movements and
hostile
regulators. Visions, however, has little to say about such
matters.
That is unfortunate, since Kaku's own experience might have
provided an
interesting perspective. A longtime antinuclear activist, he was
a leading
figure in the 1997 protest campaign against the Cassini space
probe, a
plutonium-using scientific mission to Saturn. Critics of the
anti-Cassini
movement, including me, argued that the campaign relied on gross
exaggerations of the mission's risks and that the broad
opposition to "nukes
in space" threatened to cripple space exploration. In
addressing the
uncertainties of technological change, Kaku the author might have
taken some
tips from Kaku the activist.
Yet even if technology follows a more unpredictable--and
politically
volatile--path than the one glimpsed in Visions, the book's
strengths
readily outweigh its weaknesses. Kaku's predictions are
intelligent and
thought-provoking, and his technological optimism never veers
into an
unconvincing techno-utopianism. Moreover, no one can accuse him
of thinking
small. Looking beyond the 21st century, Kaku sketches out a bold
future of
galactic colonization and more.
Drawing upon categories devised by Russian astronomer Nikolai
Kardashev,
Kaku sees technological civilizations advancing through several
phases:
Types I, II, and III. Type I refers to a global civilization, the
masters of
a single planet. A Type II civilization utilizes the resources of
an entire
solar system; such a society might even build a vast shell or
"Dyson sphere"
around its star. A Type III civilization operates on a galactic
scale,
occupying numerous solar systems. In this scheme of things,
humanity is
currently a backward society, or Type 0, but is on the verge of
attaining
Type I status.
Becoming a Type II civilization will take many centuries,
according to Kaku,
and achieving galactic Type III status requires many millennia.
But it's
worth the effort: Civilizations of Types II and III are
invulnerable to
asteroid impacts, supernova explosions, and other natural
disasters.
Toward the book's end, Kaku launches into a discussion of
wormholes,
superstrings, and other exotica of modern cosmology. After
billions of
years, even galactic civilizations are doomed, as the universe
freezes in a
Big Chill or collapses in a Big Crunch. But on the book's last
page a new
category is introduced: the Type IV civilization, masters of
space and time.
Such beings might be able to build tunnels to parallel universes.
Here,
then, is Kaku's ultimate statement of technological optimism:
Intelligent
life might survive the end of our universe.
Kenneth Silber writes about science, technology, and economics.
Copyright 2002, Reason Magazine
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