CCNet 81/2002 - 11 July  2002

"Rep. Dana Rohrbacher (R-Calif.), chairman of the space and
aeronautics subcommittee of the House Science Committee, said the
potential danger to Earth from space objects is greater than that
posed by global warming. He suggested that some of the money spent on global
warming research could be used to fund more work on tracking space objects.
Such funding could be used to first locate and track asteroids and
comets, and later to find ways to defend Earth against the threats and
eventually to use the space objects for the benefits of the Earth's
population, Rohrbacher said."
--Jason Bates,, 10 July 2002

"Let us now do the groundwork for the yet unknown environmental
challenge that will come some day in the form of a major impact. If
we don't develop anything now, and we suddenly find something on a
collision course with the Earth, our only choice will be to use nuclear
weapons, with all the associated risks of blowing the object into pieces or
not providing enough push. Therefore, it is important to test and develop
something now."
  --PROJECT B612


    Ron Baalke <>

    Steve Koppes <>

    The New York Times, 10 July 2002


    inSight, 10 July 2002

    Scientific American, 8 July 2002

    SwRI Boulder Office (Dept. of Space Studies)

    Space Daily, 11 July 2002

     Richard Clark <>

     James Perry <>

subscription might help ...)
     BBC News Online, 11 July 2002


>From, 10 July 2002

By Jason Bates
Space News Staff Writer

WASHINGTON D.C. - The U.S. government should invest more money in tracking
near-Earth objects that might threaten Earth, said members of a space
roundtable on Capitol Hill Wednesday.

While the Air Force is not tasked with tracking near-Earth objects, U.S. Air
Force Brig. Gen. S. Pete Worden said such a mission would be appropriate for
the service and an assignment could occur "in the next few years," he said.

A warning center could be run by the Air Force and coordinate with
non-military groups that currently track objects, Worden said during the
roundtable, which was titled "The Asteroid Threat: Identification and
Mitigation Strategies" and sponsored by an organization called ProSpace.

Worden, deputy director of operations for U.S. Space Command, Peterson Air
Force Base, Colo., was not attending the panel as an official representative
of the U.S. Department of Defense. He has in the past spoken often about the
need to widen the search for potentially threatening asteroids.

Currently, NASA spends about $4 million per year on programs that track
space objects larger than a kilometer in diameter (0.62 miles), said Colleen
Hartman, director of NASA's Solar System Exploration Division.

NASA, however, does not track objects the size of the recently discovered
2002 MN2, an object between 50-100 meters in diameter (roughly 50-100 yards)
that passed within 75,000 miles of Earth in June, the panelists said. The
rock was found three days after it flew by. Increased funding should be used
to track these smaller objects as well, the panelists said. Some vocal
advocates of increased asteroid monitoring around the globe have long called
for similar changes, whether funded by NASA or some other agency or

If the U.S. government were to take a more active role in tracking all space
objects, the Air Force could be responsible for tracking and cataloguing,
while NASA could be responsible for scientific investigation, Worden said.

Rep. Dana Rohrbacher (R-Calif.), chairman of the space and aeronautics
subcommittee of the House Science Committee, said the potential danger to
Earth from space objects is greater than that posed by global warming. He
suggested that some of the money spent on global warming research could be
used to fund more work on tracking space objects.

Such funding could be used to first locate and track asteroids and comets,
and later to find ways to defend Earth against the threats and eventually to
use the space objects for the benefits of the Earth's population, Rohrbacher

Other researchers in the past have suggested mining asteroids for valuable
metals and minerals as one way to make them useful to humanity. Some have
even suggested setting up small colonies on larger asteroids.

Copyright 2002,


>From Ron Baalke <>

The Associated Press, 9 July 2002

HENRYETTA - Police said today they still don't know what to make of more
than 20 reports of a mysterious fireball in the sky.

Henryetta Police Chief Audie Cole said his officers have exhausted their
investigation into the object, which streaked through the sky for about 10
to 15 seconds Saturday night. Two minutes later, residents felt the tremors
of an explosion.

Full story here:

>From Steve Koppes <>


An item of potential interest to CCNet's subscribers...


American Geophysical Union
AGU Journal Highlights - 9 July 2002

1. Bolide detection can help verify nuclear test ban treaty

New monitoring stations designed to hear ultra low-frequency atmospheric
sounds, including those of bolides (exploding meteors), are helping to
verify the accuracy of sensors that ensure compliance with the Comprehensive
Test Ban Treaty (CTBT), by listening for nuclear explosions. Brown et al.
point out that as listening systems are perfected that can pinpoint and
identify the
boom from bolides, the ability to detect the sound of nuclear detonations
improves, helping regulators catch treaty cheaters. The electronic ears are
designed to detect explosions of approximately one kiloton of TNT, which
includes nuclear tests as well as the energy released from the approximately
10 large bolides that enter the atmosphere annually. The authors compared
records from the monitors with satellite information to infer the energy,
location and physical characteristics of two large bolides over the Western
Pacific in 2000 and 2001. They suggest that as more monitoring stations
become active, the chance of not detecting, or falsely detecting, nuclear
detonations is diminished.

Title: "Multi-station infrasonic observations of two large bolides: Signal
interpretation and implications for monitoring of atmospheric explosions"

Peter G. Brown, Rodney W. Whitaker, Douglas O. ReVelle, Los Alamos National
Laboratory, Los Alamos, New Mexico; Edward Tagliaferri, ET Space Systems,
Camarillo, California.

Source: Geophysical Research Letters (GRL) paper
10.1029/2001GL13778, 2002


>From The New York Times, 10 July 2002


BEIJING (Reuters) - The head of China's state-owned television industry is
sleeping in his office to prevent hijackers from once again beaming
forbidden images of the outlawed Falun Gong movement to televisions around
the country.

An engineer at state broadcaster China Central Television (CCTV), whose
channels were among those interrupted, said Minister Xu Guangchun of the
State Administration of Radio, Film and Television (SARFT) was spending
nights at the office.

"The reason he is sleeping in his office is so that he can have instant
access if anything unexpected happens and can handle the problem instantly,"
the engineer said.

Between June 23 and 30, hijackers cut into broadcasts of: the World Cup
soccer finals, the fifth anniversary of Hong Kong's return to Chinese rule
attended by President Jiang Zemin and news of devastating floods, officials

Falun Gong, outlawed in 1999 after an estimated 10,000 followers
demonstrated peacefully outside the Communist government's leadership
compound in Beijing, has not claimed responsibility for hijacking the
satellite broadcasts.

But Beijing blames Falun Gong, which it calls an "evil-cult," for the
disruptions and said they were done in retaliation after a after a
government campaign sent thousands of its followers to labor camps or jail.

"This is extremely despicable and represents yet another crime committed by
Falun Gong," senior official Liu Lihua said.


Followers began hacking into local cable TV networks earlier this year to
show Falun Gong videos after once frequent demonstrations in Beijing petered

Falun Gong spokespeople in New York, where founder Li Hongzhi lives, said
those were the work of grassroots followers.

But hacking into national satellite beams is a big step up from cutting into
a city-wide cable television network -- especially in a year fraught with
change as a Party leadership reshuffle looms and economic reforms threaten
millions of jobs.

"Falun Gong obviously is playing a very sophisticated game of sabotage. They
know where to hit," said a television executive with a foreign company in

Experts said the hijackers could not, as one Chinese official told a news
conference, have popped into an electronics store and bought the required

"If all they wanted to do was disrupt the signal, that's relatively
trivial," said Giovanni Verlini, editor of AsiaPacific
magazine, from his base near London. "But they wanted to hijack the signal.
That's not easy at all."

Experts said the hijackers would have needed access to a multimillion dollar
earth station from which signals are beamed to satellites, or a satellite
dish at least 30 feet wide.


Government sensitivity over Falun Gong was highlighted last week when
Beijing stopped transmission of the BBC's World Service Television channel
after it showed group members protesting in Hong Kong against Jiang's
crackdown on the movement.

According to Hong Kong newspapers, CCTV scrapped live coverage of Jiang's
speech and the swearing-in ceremony of Hong Kong's Chief Executive Tung
Chee-hwa last week in fear that the satellite signal might be hijacked.

The June hijackings were aimed at the Chinese Sinosat-1 satellite, which
also serves the national weather bureau and other strategic interests, the
official news agency Xinhua said.

Sinosat-1 carries about 46 foreign and Chinese channels, according to the
Web site Most foreign channels are allowed to broadcast
only to luxury hotels and apartment blocks allowed to house foreigners.

Copyright 2002, The New York Times


>From, 10 July 2002

By Erik Baard
Special to

More than 40 years of an increasingly global push into space have placed
hundreds of artificial satellites in Low Earth Orbit (LEO) and at the same
time created a cloud of hazardous debris around the planet.

A small bolt or a chunk of metal leftover from a spent upper stage can
become a lethal weapon to the expensive and sophisticated machines should
any orbiting debris strike. Impossible as it might be to believe, the
traditional protection against unavoidable collisions is eminently low tech:
essentially, aluminum siding.

However, the U.S. Air Force Space Command, NASA and other space agencies are
seeking more innovative solutions for spotting potential threats and
eliminating them before they happen -- or if they do, increasing the odds
the satellite will survive by modifying the protective materials used.

New radar systems, saucer-like hull patch kits and new ceramic shielding are
being brought into the effort and more exotic solutions are in the offing.
The ideas include lining the walls of spacecraft and spacesuits with spider
silk to absorb impacts, using ball bearings to plug punctures, sweeping
debris aside with laser "brooms," or building robots to serve as roving
garbage scowls.

The problem is compounded as the amount of debris grows on its own. Larger
pieces become many more smaller pieces as their orbits decay and debris
collides with each other. Moreover, debris producing accidents with live
spacecraft do occur, leaving enough material in orbit to concern spacecraft
operators worldwide.

A NASA illustration referred to as the "beehive" depicts Earth shrouded by a
swarm of catalogued debris that's pushing toward 10,000 items, and reflects
the fact that millions more smaller items aren't precisely charted.

Last year, the International Space Station had to dodge a foot clamp dropped
by astronaut Jim Voss during a spacewalk before it swung around the Earth
again. The French military had to improvise a way to keep a satellite stable
when its balance boom was sliced in half after colliding with the remains of
one of their own Ariane rockets.

Still, no catastrophic crashes have occurred to threaten astronauts' lives,
but the odds have so far been on our side, observes NASA's Nicholas Johnson,
the resident space junk expert at the Johnson Spaceflight Center in Houston.

Johnson, however, downplays the panicked assessments of the danger from a
junk belt surrounding our planet. He discounts the "lightning strike"
analogy for debris collisions so often invoked by outsiders trying to convey
the rarity of such crashes.

Lightning, he emphasizes, is far more common and it doesn't usually threaten
an investment of hundreds of millions or even billions of dollars -- and
repair crews aren't stuck hundreds of miles out of reach.

Eyes Wide Open

Erring on the side of caution, space agencies and private companies are
working to eliminate risk. The first hurdle to overcome is a significant
blind spot. At present, space agencies can steadily track only pieces of
debris that stretch more than four inches (10 centimeters) across.

NASA will cast a cold snake eye on that problem in October when it makes use
of the Cobra Dane Radar System on the Alaskan island of Shemya. Cobra Dane
was designed to give early warning of ballistic missile attacks using an
L-band phased array. That powerful hardware should bring detection levels
down to two inches (5 centimeters), Johnson said.

The Japanese government and several nonprofit groups also are joining the
effort, building two new near Earth orbit scanning facilities in Okayama, a
prefecture better known for growing peaches. The stations are nearly
complete and in many ways already operating.

The Kamisaibara Spaceguard Center uses radar to detect debris in LEO, while
the Bisei Spaceguard Center uses 20-inch (50 centimeters) and 39-inch (one
meter) optical telescopes for such observations. Next year, Japan's National
Space Development Agency (NASDA) will start using its new Central Processing
Station at the Tsukuba Space Center to crunch data collected by the
spaceguard centers to calculate the orbits of registered debris.

European resources also are dedicated to the space junk hunt, including a
new 39-inch (one-meter) telescope in the Canary Islands, but they and the
Japanese rely on U.S. Space Command data for the safety of their launches,
Johnson said.

"They will not track on a routine basis 10,000 objects like we do. The
Russians have equipment to feed them routine information though. It's not
quite as good as ours, but it's very, very close," Johnson said.

NASA also is able to take snapshots of orbital debris as small as
eight-hundredths of an inch (two millimeters) across using a wide network of
ground stations, but such objects can't be tracked consistently yet, Johnson

Instead, statistical modeling is used to calculate probable hot zones of
debris and how forces like solar wind, molecular oxygen and magnetic fields
push around those flecks. One bit of help in increasing NASA's knowledge
base came from a surprising source - mirrored balls made by school children,
which provided oodles of data on orbit decay caused by those influences.

All of these programs, however, still leave space voyagers nervous at the
prospect of stepping into a vaguely understood spinning obstacle course of
millions of small, bullet-like shards. Indeed, the International Space
Station (ISS) is expected to be hit 100,000 times in its twenty-year life.
The immediate urge is to simply make them all go away. One proposal called
for "a classic garbage scowl.

"It's technically feasible but very difficult and very expensive - not cost
effective at all," Johnson said.

A team of researchers from Massachusetts Institute of Technology and NASDA
conceived robots that could be deployed from the space station, or an
independent station, and using clamps and magnets remove dangerous debris.
However, costs were much higher than maneuvering craft away from jeopardy,
or passively surviving hits.

Build a Better Spacecraft

It was Fed Whipple, the renowned cometary astronomer, who came up with the
idea for the spacecraft shielding that NASA devised decades ago. The design
is simple - a bumper layer of aluminum absorbs impacts and turns that
kinetic energy into heat. Small debris is thus turned into liquids and vapor
before it can move onto the main hull of the craft.

Layers can be added to the basic design, and many spacecraft including the
ISS supplement the shield with ceramic materials like Nextel and Kevlar,
which is perhaps best known as the stuffing in bullet proof vests. After
examining other concepts, the Japanese also chose the Whipple idea for their
new Kibo ISS module set for attachment in 2004, NASDA engineer Kuniaki
Shiraki told

More exotic materials might also be used in the construction of future
spacecraft. Carbon nanotubes have become a hot item of discussion across all
fields of engineering because, in part, the cylinders constructed from
hexagonal links of carbon atoms are believed to be perhaps the strongest
manmade material.

One primary inventor of ways to synthesize them, Nobel Laureate Richard
Smalley, is right down the road from Johnson Space Center at Rice

"We are certainly talking to them," Johnson said, but so far only tiny
strands have been produced, and at great cost. It may be a decade before
large scale manufacturing of carbon nanotubes is achieved.

A more bizarre possibility is that astronauts may one day owe their survival
to spider silk.

Science Fact Meets Science Fiction

Nexia Biotechnologies made headlines a few years ago with its "Spider Goats"
-- transgenic animals that can produce an approximation of spider silk in
their mammary glands.

The proteins are marketed as BioSteel and the company continues to refine
them to edge closer and closer to nature's product. The company also is
researching ways to grow it in plants. Dragline spider silk - the kind used
by the creatures to raise and lower themselves - has long filled engineers
with envy because of its toughness.

"Spider silk is not as strong as Kevlar, but spider silk is ... "tougher"
than Kevlar. Toughness refers to the ability to absorb kinetic energy," said
Mark Kaufmann, vice president for of corporate development and
biopharmaceuticals at Nexia.

While Kevlar can support more weight than spider silk, it's more brittle, he
said. BioSteel would allow enough give to stop more debris without getting

What that means for mission planners, Kaufmann said, is that while in tight
astronaut suits BioSteel would afford much protection. It might be great as
a layer inside the space station walls -- it's too heat-sensitive for the
exterior -- because there's enough room for a skin of it to stretch a bit on
impact. However, like nanotubes, no one has produced BioSteel in sufficient
quantity to seriously consider it for near-term projects.

Another approach, designed by Hidehiro Hata at the Kyushu Institute of
Technology, is to fill a double hull with balls that would be sucked into a
small breach like the proverbial Dutch boy's finger in the dyke. This
invention wouldn't be a true defense or even an automatic repair job, but it
would slow the gush of escaping air from seconds to minutes, giving
astronauts time to escape.

"It's a very interesting idea but it's not ready yet for the Kibo," said
Shiraki, who heads the module's shielding program

Copyright 2002,


>From inSight, 10 July 2002

Most experts agree that the solar system's most ancient rocks from asteroids
and comets should be sprinkled with microscopic diamond dust, a remnant of
ancient stars. But a group of researchers has found that at least some of
the most primitive, unaltered rock in the solar system contains no diamond
star dust at all. The finding raises questions about just how star stuff
came to form the solar system.

Researchers have found interstellar dust grains in some less-altered
meteorites by a drastic procedure: dissolving a specimen until all that
remains are the hardy mineral bits condensed in the atmospheres of stars
long ago--silicon carbide, graphite, and diamond. The diamond flecks are so
small that a single grain may contain just a few thousand atoms. Three years
ago, microscopist Zurong Dai of Georgia Institute of Technology in Atlanta
and his colleagues decided to extend the diamond hunt to microscopic
interplanetary dust particles (IDPs) that flaked off asteroids and comets
and now sift down through the stratosphere.

In an analytical tour de force, Dai and his colleagues exposed the
nanodiamonds a gentler way. They partially dissolved samples and identified
diamonds by measuring their distinctive atom-to-atom distance under
high-resolution transmission electron microscopy. As the team reports in the
11 July issue of Nature, there were plenty of nanodiamonds in four large,
cluster-type IDPs from the stratosphere. But none turned up in five smaller
IDPs, although they were just as primitive as the cluster IDPs--and
therefore also presumably came from the outer parts of the solar system,
where stellar nanodiamonds are most likely to have survived.

"It really was an unexpected result," comments microscopist Lindsay Keller
of NASA's Johnson Space Center in Houston. "Why nanodiamonds are not there
is uncertain." The simplest answer, Dai's group writes, would be that most
nanodiamonds were not formed around ancient stars at all, but in the inner
parts of the disk-shaped solar nebula as the solar system formed. But if
popular theories about chemical conditions in the early solar system are
correct, diamonds shouldn't have been able to form there.


2001 The American Association for the Advancement of Science
This item is supplied by the AAAS Science News Service


>From Scientific American, 8 July 2002

After last month's near miss with an asteroid 100 meters in diameter, a
former astronaut discusses what to do about the danger to Earth from huge
space rocks.

By Lucy Komisar

On June 15, 2002, an asteroid the size of a football field, dubbed 2002MN,
came within 120,000 kilometers of hitting Earth. The rocky body was
traveling at a speed of 36,800 kilometers per hour--and if it struck, it
would have wreaked as much destruction as a nuclear weapon. It was one of
the closest passes ever recorded for an object of that size. And astronomers
didn't detect it till three days afterward.

"Years too late," is what former astronaut Rusty Schweickart would say.
Schweickart is working with an informal group of scientists to try to
prevent the crash of a giant asteroid--one even larger than 2002MN--that he
says could destroy vast tracts of land, with disastrous, long-term effects
on the climate. Schweickart says that future asteroids that threaten to
strike must be pushed out of their orbits by advanced space technologies. He
described his concerns recently at Forum 21, a private annual
current-affairs meeting of Americans and Europeans, held this year in
Divonne, France.

The lunar module pilot for the Apollo 9 space flight in 1969, Schweickart
has worked on making several aspects of human space exploration safer. (For
more, see his bio.) But the ex-astronaut is now focused more on dangers to
Earth. He says he is worried about "the improbable but real threat to life
posed by the existence of near-earth asteroids, which are being discovered
today in quantities of hundreds."

>From Shooting Stars to Smashing Siberia

Asteroids circle the sun on paths that may cross the orbit of Earth. From
time to time through history, huge asteroids have collided with the planet.
"The reality is we get hit 100,000 times every day; but they're so small,
you call them shooting stars," Schweickart says. Earth's atmosphere protects
us from bodies smaller than 50 meters. "But when they get to the size of 50
meters, they start coming though the atmosphere instead of burning up in it.
The Tunguska thing didn't make it to the ground, but it blew up so close to
the ground that it flattened a big hunk of Siberia." The famous 1908
explosion at Tunguska leveled 2,000 square kilometers of forest. It involved
an asteroid some 100 meters in diameter. Impacts with bodies that size may
occur once in a century on average, according to estimates. Though far less
frequent, an asteroid of 10 to 15 kilometers in size could wreak the kind of
destruction that wiped out the dinosaurs 65 million years ago, says
Schweickart. Impacts of that size occur perhaps once in every 1,000,000
centuries, according to the JPL Near Earth Asteroid Tracking Team.

To learn more about such hazards, Congress in 1994 directed NASA to detect
and track near-Earth objects greater than one kilometer in size, whose
impact would create global catastrophe. Geochemistry shows that such
collisions played a significant role in the creation and destruction of life
on earth--and that this process is not over. (For more on the role of
asteroids in life's development, see "Repeated Blows," by Luann Becker;
Scientific American, March 2002, available for purchase on the Scientific
American Archive.)

In 1998 (sic), NASA formally initiated the Spaceguard Survey--adopting the
objective of finding 90 percent of all near-Earth objects larger than one
kilometer in diameter. That year, NASA also set up a Near-earth Object
Program Office at the Jet Propulsion Laboratory in Pasadena, California; a
similar facility exists in Pisa, Italy. Today, there are several teams
tracking near-Earth objects. In addition to 2002MN, Spaceguard (sic)
discovered another asteroid, 2002 EM7, that passed within 463,000 kilometers
in March 2002; this asteroid also was not found until after its flyby of

Also, in April 2002, NASA announced that its Sentry automatic impact
monitoring system had identified a potential close encounter. Asteroid
1950DA, which is two-thirds of a mile wide, is expected to come close to
Earth in the year 2880. If it hits, it would destroy everything within a few
hundred miles. Those far from ground zero would suffer from environmental
effects similar to a nuclear winter, as the dust and debris blocked the sun
for months or even years. NASA said that the odds were 300 to one that the
asteroid would hit, and that there was plenty of time--eight centuries--to
figure out what to do before then.

Thousands of Threats

But Schweickart is still worried: "Don't relax; there's more where that one
comes from." He says that one must assume that large asteroids exist in the
thousands. Astronomers estimate that there are at least 1,000 near-earth
objects of one kilometer or more and perhaps a million larger than 50
meters. "The estimate is that every month one that size [100 meters] not
only passes between Earth and the moon, but has passed between Earth and the
moon for billions of years. The difference is now we can see them because
we're looking."

Adds Schweickart: "It's like Las Vegas: the odds are the odds. We are going
to get whacked at some point, and we should know it in advance. We probably
will have decades of warning." Enough time, perhaps, to do something about
the threat.

Toward that end, he says that work on the detection side needs to continue
beyond the congressional mandate to identify 90 percent of near-earth
objects over one kilometer. "Once we get those catalogued, there are many
more in small sizes that are still very dangerous to life on Earth," he
explains. "We need to go from the program we have now to a program that
picks up things down to 300 meters in diameter. Even though they won't cause
extinction, they could cause serious global disturbances--wipe out regions,
let alone cities. And because there are a lot more [of the smaller-size
asteroids], the probability is higher we're going to find one that's going
to hit us."

Stopping the Impact

Then the task will be to prevent the impact. Right now, says Schweickart,
the only known technology for the purpose is "the wrong thing--a nuclear
weapon that you send out there to blow it up." The result, he says: "You
turn a rifle bullet into a shotgun blast."

Instead, "I'm interested in going beyond detection by using technology which
is or will shortly become available to actively change the orbits of these
potentially threatening asteroids in a controlled way, so that they no
longer threaten life on Earth," he says. "You have to go out and meet it
with a 'tugboat,' a space vehicle that would allow us to push it around for
years at a time. You change the orbit by very small velocities, which causes
it to miss, rather than hit, Earth."

The process would be based on developing rocket technology, but Schweickart
declined to be more specific, explaining, "We're talking about things that
have existed, but haven't been put to use for this purpose."

He is discussing the problem in a small, private international group that
includes astronomers, biologists, engineers and others. He says he will
reveal more about the group in six months to a year, when it is ready to
publish the results of its work. Some of the group members met in October
2001 at NASA Johnson Space Flight Center in a workshop organized by Piet Hut
and Ed Lu. It was called Project B612, after the name of the small asteroid
that was home to the Little Prince in the novel "Le Petit Prince," by
Antoine de Saint-Exupery. Among the ideas discussed during the workshop was
using a plasma-drive system such as nuclear-electric propulsion for
controlled flight near an problem asteroid.

In the meantime, understanding of the issue is not at a point where the
government could address it--that is, get a Congressional budget item and
spend money, says Schweickart. "The problem, partly--as far as the general
public is concerned--is that it would be a laugher," he says of the idea of
"somebody talk[ing] about spending a few billion dollars to push the next
asteroid out of the way." For the moment, he says, the matter should be
studied and analyzed quietly. "It's one of those things which you want to
keep people's attention on and at the same time not panic. If we keep on
with the detection program, we should know [about a problem asteroid] ahead
of time, and that will give us, with developing technology, the opportunity
to deflect it."

Lucy Komisar is New York journalist who writes on international issues.

Copyright 2002, Scientific American


>From SwRI Boulder Office (Dept. of Space Studies)

Note: B612 is the name of the small asteroid on which the Little Prince
lived (from the novel `Le Petit Prince' by Antoine de St. Exupery).

These are some informal notes, summarizing the round-table discussion during
a workshop on Deflecting Asteroids, held at NASA Johnson Space Center,
Houston, Texas, Oct. 20 2001, and organized by Piet Hut and Ed Lu (see below
for a full list of participants).


The goal of this workshop was to brainstorm about the idea of altering the
orbit of an asteroid using a plasma engine powered by a nuclear reactor. We
would like to produce a white paper, and start a discussion that hopefully
will lead to a proposal for a real mission.

We talked about the need to educate the public, and to emphasize the
difference between launching hot nuclear material, as in the case of
Cassini, and launching a nuclear reactor of the type we advocate, which is
started up only in space, after launch. Interesting examples were given of
common items such as dental X-rays with radioactivity equivalent to the
proposed 300 KW reactor at launch, which is less than 10 Curies. This is
about the same radioactivity as two truck loads of New Mexico dirt.


The discussion quickly focused on the question of what the real goal of a
project would be. Are we trying to alter the orbit of an asteroid, and
proposing a detailed study of methods to see whether the plasma engine with
nuclear reactor comes out on top? Or are we trying to define a mission for
the latter, with the prime application the deflection of an asteroid? It was
felt that having a succinct and clear goal was important, because that gets
every one on the same page, and drives the concrete implementation of the

The general feeling was to focus primarily on changing the orbit of an
asteroid. At some point soon, we will have to do a detailed study of all of
the methods proposed to change the orbit of an asteroid. However, given the
current state of our knowledge of the composition and surface properties of
asteroids, and given the huge range of sizes, orbits, and histories of
asteroids, it may not be possible to say with any certainty that there is a
single "best" method for deflecting asteroids. Therefore additional
considerations will be very important in choosing which methods merit
initial development now. We have to address questions such as how general
the proposed technologies to the problem of deflecting asteroids are, and
what other potential benefits and uses the proposed technology has?

It was felt by at least several participants that the Nuclear Electric
Plasma Rocket mission is the best choice for a first demonstration mission,
while others would prefer to see a more detailed investigations before
stating their initial preference. One advantage of our current proposal are
the capability to fly rapidly around the Solar System, a feature that is
generally useful for most asteroid mitigation strategies. In addition, such
technology would also provide a tremendous capability for all manner of
scientific probes, especially given that an abundant source of electrical
power is also part of the package.

To sum up, it is quite likely that our plasma engine plus nuclear reactor
approach may be the best way to do the job, since a major advantage of our
proposed nudging technique is that we can apply it to any type of asteroid.
However, the case is not yet clear, and we will have to investigate other
methods (cf. Jay Melosh in "Hazards from Comets and Asteroids", Univ. of
Arizona Pr., 1994, p. 1111; Sagan, C. and S. Ostro, 1994, Nature 368:501;
Sagan, C., "The Marsh of Camarina"). However, even if a case could be made
for another approach to be cheaper, it might still be worthwhile to develop
and test our approach, since a nuclear-driven plasma engine will be useful
for many other applications as well, from a manned mission to Mars to a fast
track to the Kuiper belt.

Goal: Alter the trajectory of a small asteroid in a controlled manner.

Approach: write a report about different technologies for deflecting
asteroids. If we conclude that our approach is at least reasonable, we can
propose to explore it further, since it has so many other spin-offs.

Motivation: let us now do the groundwork for the yet unknown environmental
challenge that will come some day in the form of a major impact. If we don't
develop anything now, and we suddenly find something on a collision course
with the Earth, our only choice will be to use nuclear weapons, with all the
associated risks of blowing the object into pieces or not providing enough
push. Therefore, it is important to test and develop something now.

Alternative more detailed goal formulation: A combination of two emerging
space propulsion technologies -- magnetic plasma rockets and simple
lightweight fission reactors -- offers to open up the solar system for fast,
vigorous robotic reconnaissance and human exploration. To focus and
accelerate development of these technologies, while at the same time taking
the first step toward a capability to protect Earth from cosmic impacts, we
propose a nuclear powered, plasma driven mission to fly to a Near Earth
Asteroid of ~100 m diameter, 'dock' with it, and apply thrust to measurably
change its orbit.

We also wondered whether we could develop a bigger vision. It took 12 years
to move from the very first Sputnik to a manned landing on the moon. Since
then, we have been flying circles around the Earth for more than 30 years.
Wouldn't it be time to develop a whole new mission for manned spaceflight?
Instead of going to Mars first, it would be far cheaper and simpler to bring
humans to an asteroid. If the political will could be found to do this, then
plasma engines and nuclear reactors might be the best way to achieve this.
In addition, you would establish an interesting new application for the
International Space Station: with a plasma engine you can bring humans from
there to a small asteroid without any need for chemical propulsion.

Plasma engines could bring about a revolution in Space exploitation as
dramatic as the transition from balloon aviation to powered aircraft flight.
Currently, our capability to travel around the solar system is basically at
the mercy of our gravitational environment, in much the same way that
balloons are at the mercy of prevailing winds. With the huge delta V
capability of Nuclear Electric Propulsion, we can make the transition to
true "powered flight".


The most straightforward goal is to measurably alter the orbit of an
asteroid, i.e. by changing its velocity vector by 10-20 cm/sec, so that an
asteroid aimed at the Earth could be made to miss it if the pushing was done
at least a year before predicted impact. However, there are alternative ways
to demonstrate the ability to alter the dynamics of asteroids. For example,
we could play with the spin, either despinning an asteroid, or letting it
come apart (if it is a rubble pile) by spinning it up. The latter would form
a very literal science `spin-off', which could provide enough information
about internal structure to justify a mission in its own right. Or we could
play with the companion of a double asteroid, in which we could alter the
spin as well as the orbit of the smaller of the two asteroids.

Some numbers: 70 m diameter asteroid, few x 10^8 kg, v_esc = 4 cm/sec. 100
kWatt, specific impulse 10^4, exit velocity of 10^5 m/sec, 2 Newtons. dm/dt
= 2x10^-5 kg/sec, i.e. 2 kg/day. After half a year, 10 - 20 cm/sec change in
velocity, from 300 kg fuel.

A scientific motivation to visit a small asteroid, one with a radius < 0.1
km, is that they spin faster than the centrifugal limit (see Pravec and
Harris 2000, Icarus 148, 12-20, and Pravec et al. 2000, Icarus 147,
477-486). However, three days before our workshop, IAU Circular 7735 (2001
Oct. 17) reported that the Amor asteroid 2001 OE 84 has a rotation period of
29 minutes and a diameter of 0.9 km.

There was a discussion about how to couple the engine to the asteroid. One
option would be to use a frame with a large footprint, possibly in the shape
of an umbrella frame, and to push that onto the asteroid. Whether you wind
up burying that in the soil or just draping it over the rocks may not make a
difference, as long as you exert a continuous force of order of 1 Newton,
typical for a plasma engine powered by a 100 kWatt electric source. Driving
an asteroid is like pushing a beach ball across a swimming pool using your

There was a discussion about whether despinning was really necessary.
Landing on a pole, or landing anywhere, and firing the engine only when in
roughly the right position during a rotation period might be alternatives.

Another question was whether the dust of an asteroid might gum up the works?
This may pose a problem, and we will have to look into this, but it did not
seem to be a huge stumbling block. For example, some charged or magnetized
collectors could scavenge dust before it becomes a problem; these could also
double as scientific instruments. In contrast, the prospect of sinking into
the surface is more troubling. These discussions were triggered by a
presentation of the last pictures taken by the NEAR satellite before landing
on Eros, showing how different the surface of Eros is, compared to what we
expected. Some of these pictures look like they are made of Mars, with
wind-blown structures. Also, some areas have hardly any craters, but many
rocks, the opposite of what you see on the Moon.

Some of the alternative ways to deflect an asteroid would be through a
stand-off nuclear explosion, by hitting the asteroid by another smaller
object, by heating part of the asteroid with a large flexible mirror to
evaporate part of the rock and turn it effectively into a rocket, or by
putting a mass driver on the surface, throwing rocks into space. All of
these proposals have significant problems, and it is not yet clear how these
problems compare with obstacles that may be encountered by a nuclear-driven
plasma engine mission.

Bringing nuclear weapons into space will generate an outcry amongst the
public. Playing cosmic billiards will require a proven ability to change
orbits in the first place. Deploying and focusing a large enough mirror to
evaporate some of the rock will require significant development, but may be
an option. Putting a mass driver on an asteroid, finding the right rocks,
picking them up and throwing them out will pose a very serious problem of
design for an autonomous system. Rather than throwing mass off of an
asteroid, it could be more practical to blow it off, by burying an explosion
under the surface and expelling a plume of material. From a momentum/energy
standpoint, that might be more efficient than vaporizing surface matter by a
stand-off explosion or by a giant mirror. Clearly, these various options
need further study.

It might be possible to use a nuclear-driven plasma engine to alter the
orbit of an asteroid in a controlled manner without landing on the surface.
With a nuclear power source available, an ablative laser system may heat
part of the asteroid, turning it into rocket. Besides adding a second way to
move an asteroid, a non-contact system might also provide valuable
information about the surface materials and where the best landing location
might be. Comparison of the effectiveness of two techniques would be
extremely valuable.

Obviously, whatever we will propose, we should go to an asteroid that is not
currently on a Near-Earth orbit, in order to prevent possible public fears
of some worst-case scenario (sabotage?) causing an Armageddon.


It seems that NASA has focused mainly on the search for NEOs, not on
visiting them in order to do something with them. Nor has anyone else yet
tackled this goal. With our project, we are entering new terrain.

With the Clementine mission, first to the Moon with the intention of going
to an asteroid (it never got there), the view was that NASA was not in the
business of defense or deflection, that that would be DOE's or DOD's role.

There have been many `grey papers' and discussions about doing something
with asteroids, but nothing amounted to anything more specific than

There is a new Decadal committee of solar system exploration, headed by Mike
Belton, who is really interested in this type of stuff, including the Deep
Interior mission.

One of the participants mentioned that if he would be a reviewer for NASA,
he would be worried about the cost of our project. It is like a NEAR
mission, but more expensive, while NEO searches currently cost only a few
million dollars per year. Also, the chance is very small that something will
be found that will pose a severe threat to us in the next ten or twenty
years; most likely if we find a serious threat, we will have many years to
think about doing something about it.

The weight for the nuclear reactor would be 2-3 tons, for 100 kWatts. The
power system itself (reactor, shield, converter, power conditioning,
radiator, boom, etc.) should cost ~$300M to $400M. The cost is also tied to
the mass bogie - a 2 ton system will cost more the a 3 ton one (and will
have more technical/programmatic risk). This implies a total weight of the
spacecraft to be at least 5 tons, making it a Galileo/Cassini type mission.
The total price for the entire mission will be well over a billion dollars.
As long as we are dealing with a zero-sum game, it will be very difficult to
get NASA to pay for this. Promoting the mission as a
technology-demonstration may therefore be the best way to go, rather than
purely as a measure to protect the Earth.

To play the devil's advocate against the latter approach, note the following
statistics. Km-sized asteroid/comets should strike the Earth once every
500,000 years or so. The interval between impacts from a less hazardous
bolide capable of delivering 1000 MT should be once every 60,000 years.
Tunguska events probably occur once every few hundred years. Thus, one could
argue that the odds are low enough that this is not a pressing mission for
the US to undertake today. Moreover, it is very likely that an asteroid on
its way to strike the Earth will pass close to Earth several tens of years
before impact. This increases reaction time and decrease the need to take
immediate steps on this issue.

It was noted that NASA is keen on commercialization: mining an asteroid
might be of interest. If we get congress to put this in as a line item, NASA
will get the new technologies for free.

We have to add many components to make sure we can do the rendezvous,
laser-altimeter, etc. etc., many navigation instruments, star trackers, we
have to know very accurately where we are pointing our thrusters, to within
a percent or ideally even a lot better. Attitude control with hydrazine or
wheels or so. With a small asteroid, you are probably not going to orbit it,
but fly in formation; you will hardly feel its gravitation. Then there is
the problem of the time lag. We did it without autonomy on NEAR, but you
might want to add some autonomy, to get higher accuracy because of quicker
feed-back. You can say very fast "we are going to put it on the surface and
stop its spin". But in practice its not that easy.

It was noted that a technology that allows you to manipulate asteroids can
be used for destructive methods as well. This is a point that Carl Sagan has
made, and which has appeared widely in print (cf. Harris et al. in "Hazards
from Comets and Asteroids", Univ. of Arizona Pr., 1994, p. 1145). For all
its drawbacks, nuclear explosives are too blunt a tool to aim an asteroid at
enemy territory, by carefully changing its orbit. However, if you develop a
more precise way of driving an asteroid, you open up this issue again. Carl
Sagan stressed that occasionally you get a madman in power; in the 20th
century you had two people, Hitler and Stalin, and who knows whom you will
get in the future. We discussed this question, and we concluded that we will
have to take this aspect seriously.


Phase 1:
We talked about developing a concrete proposal for a first
mission.  Here is a possible list of Chapter Headings for a
Phase 1 Study:
               Project B612
     1. Introduction & Goal
     2. Options and Trade-offs
     3. Asteroid Threat
     4. History
     5. Action/response needs & requirements
     6. Mission requirements & characteristics
     7. Safety
     8. Technology Development Status
         a. Propulsion
         b. Power
         c. Navigation & Control
         d. Landing and attachment systems
         e. Communications
         f. Other
     9. Schedule
     10. Funding Analysis and Options
     11. Organizational Design
     12. Legal and Public Policy/Perceptions Issues
     13. Conclusions & Recommendations

Phase 2:
The mission would demonstrate the following mission segment:
-- rendez-vous
-- land & positive contact
-- null rotation of asteroid
-- apply delta V through non-explosive methods
-- high-power electric propulsion


It would be good to develop a roadmap, of which this mission is only the
first mission.

We talked about various funding options. Only NASA? Also DOE and perhaps
even DOD? How about international contributions? Or private funding?

A legal issue was raised. If we will partly get funding from private
sources, there are various legal models, and we have to be careful, and to
anticipate what options would be best.

It was mentioned that last March a workshop was held, which happens once
every few years, of an collection of international space groups; one of the
five topics was impact hazards. The UN/AIAA/CEAS/IAA report was available on
the following web site: (web
site currently broken; if it works for you, go to pg. 15 of the report,
about pg. 20 of the pdf document).

They also discussed the difficulty of multiple bureaucracies and the need
for strong leadership. Also, the Brits have had a parliamentary debate on
NEO hazards. They even founded a British national center for NEO.

It was noted that in a way this is the ultimate environmental project, and
that there could thus be a lot of prestige in it, to fund this privately.

The preliminary conclusion was that it was difficult to judge where the best
tradeoff lies: adding a mix of private and/or international money may make
it far more difficult to control the program and to avoid getting trapped in
bureaucracies. However, if we could get private money for a phase 1 study,
that would be great. A few million dollars would be ideal. You could then
advertise it and force the government to pay for the follow-up phase, if it
gets enough popular support.


With several million dollars, we could provide the activation energy, with a
very detailed initial study resulting in the necessary technical reports as
well as glossy brochures, to get it all going.

As a step to get there, we could try to get 50,000 dollar in order to
develop a mini-glossy brochure, together with a few preliminary reports,
which we can then use to get the several million dollars for the phase 1
study. We could approach the Planetary Society.

Clark Chapman, Dan Durda, and Bill Merline volunteered to set up a web site
for our project, at SwRI, with help from Franklin Chang-Diaz's nephew.


Here is a list of participants in our workshop, followed by
their email addresses and tel. numbers (Bill Bottke, Tony
Dobrovolskis and David Morrison were present via telecom):

William Bottke      []          
Dennis Byrnes       []     
Franklin Chang-Diaz []
Clark Chapman       []        
Tony Dobrovolskis   []        
Dan Durda           []           
John Grunsfeld      []   
Piet Hut            []                     
Don Korycansky      []            
Stanley Love        []     
Ed Lu               []        
Andrew Petro        []     
Dan Mazanek         []        
Bill Merline        []    
David Morrison      []           
David Poston        []                  
Dan Scheeres        []               
Rusty Schweickart   []                      
Jared Squire        []       
Bobby Williams      []      

SwRI Boulder Office (Dept. of Space Studies)


>From Space Daily, 11 July 2002

Pasadena - Jul 11, 2002
NASA's Comet Nucleus Tour launched July 3, will rely on the Jet Propulsion
Laboratory's navigation team to guide the craft on its tricky journey toward
two comets to find out how the icy, rocky bodies evolve as they approach the

The spacecraft is poised for a 15-month journey to Comet Encke followed by a
two-and-a-half-year trip to Comet Schwassmann-Wachmann 3. The mission was
conceived so that scientists could compare the older, less active Encke to
the younger, dust-clouded Schwassmann-Wachmann 3. The different targets pose
a challenge to the navigators, too.

"We'll be flying by quickly and close to Comet Encke. There will be just ten
minutes of time to take the science data, and our job is to protect that
time," said Tony Taylor, chief of the navigation team at JPL, in Pasadena,

"On the other hand, Comet Schwassman-Wachmann 3 has more dust and gas
shooting from its inner body. We will fly past it a bit farther away to
avoid being hit by a particularly large particle, and we'll have more time
to observe the comet."

The navigation team will guide the spacecraft through its complex orbit. The
complex launch plan will first send the spacecraft into an Earth-circling
orbit. After six weeks, the navigators will steer the spacecraft toward the
first of the two comets.

"It's like having two launches," said Dr. Bobby Williams, a member of the
navigation team and the leader of the JPL navigation team that landed the
Near Earth Asteroid Rendezvous spacecraft on the asteroid Eros in February
2001. "We have to fire a rocket to go into orbit around Earth and then about
six weeks later fire another rocket to push the spacecraft out of Earth

The spacecraft will fly by each comet at the peak of its activity as it
approaches the Sun. During each encounter, the target comet will be well
situated in the night sky for astronomers worldwide to make concurrent
observations from the ground.

Protected by its dust shield, the spacecraft will fly by each comet nucleus
to within a distance of 100 kilometers (62 miles). The most intensive data
taking will occur within a day or so of each encounter.

The mission's design is flexible so that the spacecraft can be retargeted to
intercept an unexpected comet visitor. If a "new" comet passes close enough
to Earth's orbit, mission managers at the Johns Hopkins University Applied
Physics Laboratory, Laurel, Md., will design a new flight path to take
advantage of the opportunity to study the new comet. The JPL navigation team
will then calculate the amount of fuel the spacecraft should burn, and for
how long, to put it on the right path.

JPL will also provide communications support through the Deep Space Network,
the worldwide series of antennas that provide radio communications for all
of NASA's interplanetary spacecraft.

"JPL's participation is essential to making the mission happen," said Dr.
Joseph Veverka, principal investigator and leader of the mission from
Cornell University, Ithaca, N.Y. "We have to get the spacecraft very close
to the comets and we have to communicate with the spacecraft and we
couldn't do those things without JPL. And one of the world's experts on
comets, Dr. Don Yeomans of JPL, is part of our science team."

Copyright 2002, SpaceDaily



>From Richard Clark <>

Hello Benny,

The recent discussion on impact events triggering a larger human response
has been quite interesting. I would point out that, on a very small scale,
there has already been an incident of (anthropogenic) celestial fireworks in
a politically tense situation. During the Gulf War an upper stage from a
recent Russian launch reentered on a track that took it over Israel. It did
not trigger a response from Israel. A study of this event would be useful.
It is the closest we've come to the sort of event envisioned as a threat.

Was Israel given advance warning that there would be an entry over Tel Aviv?
Doubtful, the precise location of an uncontrolled reentry of an object in a
circular orbit is notoriously difficult to predict ahead of time. Only if
there is a NAVSPASUR pass on the final one or two orbits can this be done
with any degree of confidence. I don't have any details such as the final
TLEs for the upper stage, or even the NORAD or COSPAR designation to see if
this might have happened. On the other hand, a general warning of a pending
reentry that could happen in their area could have been issued to commanders
in the area.

How about recognition of the nature of the event in real time? How much
training in orbital mechanics and entry dynamics is included in the training
of the Patriot battery operators, etc? Observations from the public (all to
often in the form of UFO reports) following an entry, or sometimes an
evening launch out of VAFB in southern California show that humans are not
able to judge size and distance in unfamiliar situations. A comparison of
UFO reports with the actual cause, once determined, of a sighting
illustrates this. Reports from pilots and policemen or other 'reliable
authority figures' can be as far off the mark as those from the town drunk.
I am very doubtful that reports based on visual observations by the troops
in the field would have calmed any initial alarm caused by the entry.

However, that night in Israel the sky was being swept by numerous radars in
anticipation of Scud launches from Iraq. I'm not sure how extensive the
coverage at orbital altitudes would have been. It might have been this radar
tracking that provided the confirmation that the entry was not a threat.

A detailed, authoritative reconstruction of the events that night would be
most interesting in the light of our current discussion.

Richard Clark


>From James Perry <>


Your response to Grinspoon was right on the mark.  CCNet takes the right
approach, and I think you should remain firmly anti-alarmist. Besides, I
really enjoy forwarding CCNet articles to my Green friends and then hearing
them rant and froth...


subscription might help ...)
>From BBC News Online, 11 July 2002

Science lessons for teenagers are becoming so boring they are putting pupils
off science for life, a cross-party group of MPs is expected to warn.

GCSE science is based on rote learning of facts of little use and has made
practical work a "tedious and dull activity", the Commons science and
technology committee was to report.
The situation could have a major impact on scientific research in the future
with pupils not inspired to continue with science beyond 16, it is feared.

The report, published on Thursday morning, will call for greater flexibility
in the science curriculum and greater focus on contemporary science.

The MPs were likely to blame the exam boards and the Qualifications and
Curriculum Authority for the problem, saying their approach to testing GCSE
science was preventing good science from being taught in schools.


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CCNet contributions do not necessarily reflect the opinions, beliefs and
viewpoints of the moderator of this network.



Aerospace Daily, 11 July 2002

The Department of Defense should set up an early warning center so the
information it collects about asteroids, comets and other near-Earth
objects (NEOs) can quickly be shared with other countries, according to
Air Force Brig. Gen. Simon "Pete" Worden, deputy director for operations
at U.S. Space Command.

Worden said July 10 at a Capitol Hill space round-table that a June
incident involving an asteroid over the Mediterranean Sea underscored
the need for a center to warn about natural objects that could cross
Earth's orbit. When the asteroid, estimated at five to 10 meters in
diameter, collided with the Earth's atmosphere, it released a burst of
energy comparable to the nuclear bomb dropped on Hiroshima, Japan, in
World War II.

If the June 6 burst had occurred over India or Pakistan, which were on
the brink of war at the time, it could have been mistaken for a military
attack, pushing the two countries into a full-scale conflict, he said.

"Neither of those nations has the sophisticated sensors we do that can
determine the difference between a natural NEO impact and a nuclear
detonation," Worden said. "The resulting panic in the nuclear-armed and
hair-trigger militaries there could have been the spark" for a nuclear

DOD currently gives NEO information to foreign countries on an informal
basis, a process that can take weeks. Formalizing the process with a new
early warning center could expedite that process, Worden said.

A recent study concluded that such a center could be formed with just
five to 10 people at U.S. space facilities in Cheyenne Mountain, Colo.,
Worden added. While the center would need only a modest amount of
equipment to get started, it likely would influence the requirements for
the next-generation space surveillance system now under development. At
the moment, DOD has not given anyone the go-ahead to set up such a

Worden also said that the U.S. should step up efforts to develop
microsatellites, which can be produced and launched with far less money
and time than regular satellites. Microsatellites could collect detailed
information about a specific NEO, including its internal structure. Such
information could be critical to figuring out how to divert the NEO from
Earth's path.

Building a new set of ground-based telescopes that are three meters in
diameter also would be helpful because it would allow the U.S. to scan
the entire sky every few weeks, according to Worden. The nation's most
effective NEO sensor, MIT's Lincoln Lab LINEAR facility in New Mexico,
misses many NEOs because its main optics are only one meter in diameter.

Another roundtable speaker, Colleen Hartman, director of NASA's solar
system exploration division, said 602 NEOs with a diameter of one
kilometer or more have been identified, a number that could grow to as
many as 1,080 with further study. The U.S. has focused its detection
efforts on such large NEOs because they could cause a global
catastrophe. NASA is studying ways to detect smaller ones, which could
number in the hundreds of thousands, because they still could cause
serious devastation, Hartman said.

- Marc Selinger (

Copyright 2002, Aerospace Daily

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forany other purposes without prior permission of the copyright holders.
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found at DISCLAIMER: The
opinions, beliefs and viewpoints expressed in the articles and texts and
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CCCMENU CCC for 2002