PLEASE NOTE:

• Information circulated on the cambridge-conference network is for
  scholarly use only. The attached text may not be reproduced
  or transmitted without prior permission of the copyright holder.

*

CCNet 93/2001 - 24 August 2001
------------------------------


"They're called catastrophists, a group of British scientists who
question many of the aspects of Darwinian evolution and argue that life
on Earth and the geology of the planet have been constantly reshaped by
asteroid strikes and other external shocks."
--Barry James, International Herald Tribune, 23 August 2001


"Ceres, the first asteroid (minor planet) to be discovered in the
Solar System, has held the record as the largest known object of its kind
for two centuries. However, recent observations at the European
Southern Observatory with the world's first operational virtual
telescope, Astrovirtel, have determined that the newly discovered distant
asteroid '2001 KX76' is significantly larger, with a diameter of 1200
km, possibly even 1400 km."
--European Space Agency, 23 August 2001


"In 1999, the NEO community developed the Torino scale, a hazard
index structured something like the Richter Scale for earthquake
magnitude. The Torino scale was intended to improve definitions and
communications between scientists, as well as their ability to communicate
potential threats to the press and the public. But so far the Torino scale
has been nearly nonexistent as far as the public is concerned."
--Robert Britt, Space.com, 23 August 2001



(1) VIRTUAL TELESCOPE OBSERVES RECORD-BREAKING ASTEROID
    European Space Agency, 23 August 2001

(2) CHALLENGER CROWNED KING OF ASTEROIDS
    MSNBC, 24 August 2001

(3) ASTEROID NO THREAT, DESPITE RUMORS OF EARTH IMPACT
    Space.com, 23 August 2001

(4) IT CAME FROM OUTER SPACE: BRITISH NEO-CATASTROPHISM
    International Herald Tribune, 23 August 2001

(5) PROFESSOR SIR FRED HOYLE
    The Guardian, 23 August 2001

(6) BIG ENOUGH TO BURY DARWIN
    The Guardian 23 August 2001

(7) WELL PRESERVED METEORITE YIELDS CLUES TO CARBON EVOLUTION IN SPACE
    Andrew Yee <ayee@nova.astro.utoronto.ca>

(8) MINING ASTEROIDS
    IEEE SPECTRUM Online, 23 August 2001

(9) ASTEROID 2001 PM9
    Carl Hergenrother <chergen@fortuna.lpl.arizona.edu>

(10) 2001 PM9: WE LUCKY FEW
     Larry Robinson <lrobinsn@ix.netcom.com>

(12) 2001 PM9 & INTERNATIONAL SPACE COOPERATION REPORT
     Andy Smith <astrosafe@yahoo.com>

(13) PLANETARY DEFENSE
     Christian Gritzner <christian.gritzner@mailbox.tu-dresden.de>

(14) "RED HOT KILLER ASTEROID"
     Phil Plait <badastro@badastronomy.com>

(15) DEFLECTION OF ASTEROIDS WITH NUCLEAR BOMBS
     Michael Paine <mpaine@tpgi.com.au>

(16) DEFLECTION OF ASTEROIDS WITH NUCLEAR BOMBS
     John Michael Williams <jwill@AstraGate.net>

(17) UPDATE ON TUNGUSKA
     Luigi Foschini <foschini@tesre.bo.cnr.it>

(18) SCIENCE AND APPLICATIONS OF THE SPACE ENVIRONMENT
     Duncan Steel <D.I.Steel@salford.ac.uk>

(19) TAGISCH-LAKE METEORITE & SIR FRED HOYLE
     Hermann Burchard <burchar@mail.math.okstate.


===========
(1) VIRTUAL TELESCOPE OBSERVES RECORD-BREAKING ASTEROID

>From the European Space Agency, 23 August 2001
http://sci.esa.int/hubble/news/index.cfm?oid=28146
  
Virtual Telescope Observes Record-Breaking Asteroid - New data show that
'2001 KX76' is larger than Ceres  

23-Aug-2001
Ceres, the first asteroid (minor planet) to be discovered in the Solar
System, has held the record as the largest known object of its kind for two
centuries. However, recent observations at the European Southern Observatory
with the world's first operational virtual telescope, Astrovirtel, have
determined that the newly discovered distant asteroid '2001 KX76' is
significantly larger, with a diameter of 1200 km, possibly even 1400 km.

Astrovirtel provides decisive data about 2001 KX76

By combining data from the world's first operational 'virtual telescope',
Astrovirtel, with that from a conventional telescope at the European
Southern Observatory (ESO) at La Silla (Chile), European astronomers have
determined the size of the newly found, remote asteroid, 2001 KX76.

Their measurements indicate that this icy rock has a diameter of at least
1200 km and is therefore larger than any other known asteroid in the Solar
System. The previous record-holder, the asteroid Ceres, was also the first
object of its type to be discovered - by the Italian astronomer Giuseppe
Piazzi on January 1, 1801. Its diameter is about 950 km, relegating it to
second place after holding the asteroid size record for two hundred years.

This conclusion is based on data from Astrovirtel, which has been operating
at the ESO headquarters in Garching (Germany) for about one year. This
advanced prototype science tool which in effect mimics a telescope provides
astronomers with access to a wide variety of high-quality data. The first
scientific results from Astrovirtel have allowed a substantial improvement
of the accuracy of the computed orbit for 2001 KX76. It is now possible to
confirm that this object is just outside that of the most remote known major
planet Pluto. Further analysis carried out by the team seems to indicate
that the orbit of 2001 KX76 is very similar to that of Pluto. Asteroid 2001
KX76 is even larger than Pluto's moon Charon (diameter 1150 km), adding fuel
to the fiery discussions concerning Pluto's status as a 'major' or 'minor'
planet. The new data show that 2001 KX76 is about half the size of Pluto
(diameter about 2300 km) and this increases the likelihood that there are
other bodies still to be discovered in the outer Solar System that are
similar in size to Pluto.

Observations of 2001 KX76

On July 2 2001, a group of American astronomers lead by Robert Millis
(Lowell Observatory, Flagstaff, Arizona) announced the discovery of a
seemingly rather large so-called Kuiper Belt Object, designated 2001 KX76.
Objects of this type are icy planetary bodies that orbit beyond Neptune in
the distant region of the Solar System known as the Kuiper Belt. More than
400 such objects are currently known and they are believed to be remnants of
the formation of the Solar System and consequently amongst the most
primitive and least-evolved objects available for study in the Solar System.


The first observations of 2001 KX76 were quite sparse, so the initial
estimates of the size of the new asteroid were very uncertain. However, it
did look large, possibly about the same size as the largest known asteroid,
Ceres, the diameter of which had earlier been measured at about 950 km.

A team of German, Finnish and Swedish astronomers took the initiative to
carry out a more accurate measurement of the size of 2001 KX76 within a
unique collaboration between Astrovirtel and a conventional ESO telescope at
the La Silla Observatory in Chile. The results show that this object is
definitely the largest Kuiper Belt Object so far discovered.

Determining the size of a distant asteroid

In order to measure the size of any asteroid, it is necessary first to
determine its orbit around the Sun, which gives its present distance from
the Earth. The next step is to estimate its 'albedo', i.e. the percentage of
incident sunlight reflected from its surface. From these numbers and the
measured, apparent brightness of the asteroid (as seen from the Earth), its
diameter can finally be derived.

To determine the orbit of 2001 KX76 the group used Astrovirtel to apply
automatic search software to scan through 'old' photographic plates obtained
with various telescopes, as well as recent CCD observations made with the
ESO Wide Field Imager (WFI) at the MPG/ESO 2.2 m telescope on La Silla
(Chile).

The search was successful: the astronomers were able to find several
photographic plates on which faint images of 2001 KX76 could be identified -
some of these plates had been obtained as early as 1982. The exact sky
positions were measured and with accurate positional data now available over
a time span of no less than 18 years the team was able to compute the first,
high-precision orbit of 2001 KX76. This also allowed the current distance
from the Earth to be determined which turned out to be about 6.5 billion km
corresponding to 43 times the distance of the Earth from the Sun, or nearly
one-and-a-half times farther from the Sun than Neptune.

Combining this with a realistic assumption for the albedo of 2001 KX76 of 7
percent (corresponding to the albedo of another well-observed Kuiper Belt
Object, Varuna, and comparable to that of our own Moon), a diameter of no
less than 1200 km was obtained. Assuming instead an albedo of 2001 KX76 of
only 4 percent - a typical value for icy cometary nuclei - leads to the even
larger (although less likely) value of 1400 km.

A real name for 2001 KX76

Thanks to the work of this group of astronomers, the orbit of 2001 KX76 may
now be considered relatively secure and it may therefore soon receive a real
name. Following astronomical tradition, the discoverers have the right to
make a suggestion. The current custom dictates that a Kuiper Belt Object
must be given a mythological name associated with creation. The name must
then be confirmed by the International Astronomical Union before becoming
official.

With a little bit of luck ...

The observations made with ESO's Wide Field Imager were crucial for this
work to succeed in that they allowed this object's path to be tracked back
in time. However, luck admittedly also played a key role. "These
observations were originally made for a completely different project," says
Gerhard Hahn, team-leader for the project. "And we found the image of 2001
KX76 right at the edge of the WFI frames."

Jenni Virtanen, another member of the team, adds: "And if we hadn't used our
powerful methods to improve the orbit we would still be searching through
the archives."

Arno Gnaedig, a German amateur astronomer and team member, performed the new
and accurate position measurements and also calculated the new orbit on his
home computer: "To me this is a wonderful example of the fruitful
collaboration that can take place between well-equipped amateur astronomers
and professional astronomers," he says. "The Web and the access to 'virtual
observatories' means that amateur astronomers - located far from any 'real'
professional telescopes - can also make important contributions."

Following this success, the group is currently working on a study of the
long-term orbital evolution of 2001 KX76, accounting for orbital
uncertainties, in order to investigate the dynamical behaviour, and its
relationship to both Pluto and Neptune.

The Astrovirtel coordinator, Piero Benvenuti, comments: "These results are
thrilling for more than one reason. The latest in modern astronomical
technology combined with a novel scientific procedure have been able to
produce results that would otherwise have been very difficult to achieve. I
am very delighted to see the first important scientific results materialise
from our work with Astrovirtel."

The 'Virtual Observatory' concept, for which Astrovirtel is a prototype, is
the start of a new era in astronomy. A larger study project called the
'Astrophysical Virtual Observatory' is about to start within the Fifth EC
Framework programme as a collaboration between ESO, ESA (ST-ECF), the
University of Edinburgh (UK), CDS (Strasbourg, France), CNRS (Paris, France)
and the University of Manchester (UK).

Credit: ESA, ESO, Astrovirtel & Gerhard Hahn (German Aerospace Center, DLR,
Berlin)

Notes for editors

This is a joint Press Release by the Space Telescope European Coordinating
Facility (ST-ECF) and the European Southern Observatory (ESO).

Members of the group of scientists involved in these observations are:
Gerhard Hahn (German Aerospace Center, DLR, Berlin), Claes-Ingvar Lagerkvist
(Uppsala University, Sweden), Karri Muinonen, Jukka Piironen and Jenni
Virtanen (University of Helsinki, Finland), Andreas Doppler and Arno Gnaedig
(Archenhold Sternwarte, Berlin, Germany) and Francesco Pierfederici
(ST-ECF/ESO).

Acknowledgments: Observations from Siding Spring Observatory (Digitized Sky
Survey 1), and NEAT/JPL were also used in the orbit determination.

Contacts

Lars Lindberg Christensen
Hubble European Space Agency Information Centre, Garching, Germany
Phone: +49-89-3200-6306 (089 in Germany)
Cellular (24 hr): +49-173-38-72-621 (0173 in Germany)
E-mail: lars@eso.org


Richard West
European Southern Observatory, Garching, Germany
Phone: +49-(0)89-3200-6276
E-mail: rwest@eso.org

Gerhard Hahn
German Aerospace Center, DLR, Berlin, Germany
Phone: +49-30-670-55-417 (030 in Germany)
E-mail: gerhard.hahn@dlr.de

Karri Muinonen
Observatory, University of Helsinki, Finland
Phone: +358-(0)9-19122941
E-mail: Karri.Muinonen@Helsinki.Fi

Claes-Ingvar Lagerkvist
Uppsala Astronomical Observatory, Sweden
Phone: +46-18-471-5977
E-mail: classe@astro.uu.se

More about Astrovirtel

Astrovirtel is a collaboration between Europe's largest astronomical
organisation, the European Southern Observatory (ESO), and the European
Space Agency (ESA). It is the first virtual astronomical telescope dedicated
to data mining and provides an interface between the scientists and the huge
amounts of data stored in scientific archives. This interface partly
consists of a combination of the development of special software tools that
incorporate advanced data query methods and the dedicated support of archive
astronomers.

Astrovirtel is a response to the rapid developments currently taking place
in the fields of telescope and detector construction, computer hardware,
data processing, archiving, and telescope operation.

Astronomical data archives increasingly resemble virtual gold mines of
information. Nowadays astronomical telescopes can image increasingly large
areas of the sky. They use an ever greater variety of different instruments
and are equipped with ever-larger detectors. The quantity of astronomical
data collected is thus rising dramatically, generating a corresponding
increase in potentially interesting research projects. Astrovirtel
facilitates such projects by enabling astronomers to access these archives.

Astrovirtel is supported by the European Commission (EC) within the 'Access
to Research Infrastructures' action under the 'Improving Human Potential &
the Socio-economic Knowledge Base' of the EC Fifth Framework Programme.

============
(2) CHALLENGER CROWNED KING OF ASTEROIDS

>From MSNBC, 24 August 2001
http://www.msnbc.com/news/586894.asp

Challenger crowned king of asteroids    
Space Shorts: New diameter calculation favors 2001 KX76    
    
COMPILED BY MSNBC 
   
Aug. 23 -  Ceres, the first asteroid to be discovered, has held the record
as the largest known object of its kind for two centuries. However,
calculations using data collected by the world's first operational virtual
telescope have confirmed that the newly discovered asteroid 2001 KX76 is
significantly larger.    

EUROPEAN ASTRONOMERS say they used the "virtual telescope," known as
Astrovirtel, as well as other data from a conventional telescope at the
European Southern Observatory in Chile to determine that 2001 KX76 had a
diameter of at least as 750 miles (1,200 kilometers).

That would make it larger than Ceres, which was discovered on Jan. 1, 1801
and has a diameter of about 600 miles (950 kilometers). The result has
raised hopes that other celestial bodies might be found on the rim of the
solar system that are similar in size to the planet Pluto, which measures
about 1,425 miles (2,300 kilometers) in diameter.

2001 KX76, discovered on July 2 by a group of American astronomers, is just
one of hundreds of icy planetary bodies that orbit beyond Neptune in the
distant region of the solar system known as the Kuiper Belt. Such objects
are believed to be remnants of the formation of the solar system.

The first observations of 2001 KX76 were sparse, so the initial estimates of
the size of the new asteroid had a high degree of uncertainty. However, it
did look large, possibly about the same size as Ceres.

A team of German, Finnish and Swedish astronomers took the initiative to
carry out a more accurate measurement of the size of 2001 KX76, using
conventional observations as well as the analysis from Astrovirtel, a
prototype science tool at the ESO's headquarters in Germany that mimics a
telescope.

Astrovirtel scanned through the recent observations and past photographic
images of the sky - and found several faint images of 2001 KX76, going back
to 1982. Using those additional sky locations, the scientists could compute
the first high-precision orbital data for the asteroid. The scientists
combined that distance information with what they knew about the reflective
characteristics of asteroids, enabling them to estimate that the asteroid's
diameter ranged between 750 and 875 miles (1,200 to 1,400 kilometers).

Thanks to the work of this group of astronomers, the orbit of 2001 KX76 may
now be considered relatively secure, and it may therefore soon receive a
real name. Following astronomical tradition, the discoverers have the right
to make a suggestion. The current custom dictates that a Kuiper Belt Object
must be given a mythological name associated with creation. The name must
then be confirmed by the International Astronomical Union before becoming
official.
      
Copyright 2001, MSNBC

===============
(3) ASTEROID NO THREAT, DESPITE RUMORS OF EARTH IMPACT

>From Space.com, 23 August 2001
http://www.space.com/scienceastronomy/solarsystem/asteroid_threat_010823.html

By Robert Roy Britt
Senior Science Writer

A newly discovered asteroid whose orbit around the Sun had only been
tentatively investigated was rumored last weekend to be on a collision
course with Earth.

As with similar cases in recent years, further scientific observations
showed the asteroid, called 2001 PM9, poses no threat.

But before these additional observations could be made, the initial data
collected on the space rock was released on a public Web site called NEODyS,
which is run by scientists who hunt for and study potentially hazardous
asteroids. The site is intended to inform other astronomers of
newly found asteroids, in part so that additional observations can be made.

However, when 2001 PM9 was announced on NEODyS (Near Earth Objects Dynamic
Site) on Friday, Aug. 17, it included odds of a possible impact in 2005 and
2007 that were better than 1-in-a-million. Slim, but not none.

By early this week, the odds had been revised to none. Yet over the weekend,
a handful of other Web sites disseminated the earlier information, some
adding personal fears to their reports.

On a Web site called The Hot Sheets, a visitor posted details of the
asteroid that included this warning: "Dear Readers, following are some facts
that ought to set you right back in your chair, grow you some grey hairs --
or cause a certain amount of lost sleep."

Not the first time

While not widely published in the popular press, the case of 2001 PM9
mirrors other instances in which the public was warned of possible Earth
impacts that later turned out to be no threat at all. The first and most
infamous was asteroid 1997 XF11, which in 1998 was said to be on a
course that might hit the planet in 2040. Most major news organizations
reported the threat, which scientists later withdrew.

The scenario was repeated in 1999, when asteroid 1999 AN10 was said to have
a small chance to hit Earth in 2039. The release of that data, and
subsequent publication by some media outlets, was criticized by researchers
who still had a 1997 XF11 hangover and worried that their
credibility was being eroded.

NEODyS was created by a group of researchers at the University of Pisa in
Italy -- the same researchers who published the initial data about 1999
AN10. One goal was to provide better communication between scientists
regarding asteroids, so that asteroid scares could be
avoided.

But anyone can access the information, and other NEO (Near Earth Object)
organizations also reported the initial 2001 PM9 data. The first reports of
2001 PM9 were disseminated by NASA's Jet Propulsion Laboratory (JPL) and
another research group called Spaceguard Foundation.

However, Donald Yeomans at JPL said his organization did nothing wrong.
Though data on 2001 PM9 first appeared on JPL's Potentially Hazardous
Asteroid list on Aug. 13, Yeomans said it was a "routine posting of orbital
data and certainly not an announcement of any type of threat."

No impact probabilities were listed on the JPL site, he said.

"At no time did JPL formally or informally release any announcement about
asteroid 2001 PM9," Yeomans said. "Our activities were restricted to
requesting new data, soliciting archival data and working to compute updated
orbits so the results could show, as quickly as possible, that
this object was not a threat. We were rather proud that these activities
took place so rapidly that by last Friday, the computations showed no real
threat. That is exactly how things are supposed to work."

Floundering community of researchers

Brian Marsden is director of the International Astronomical Union's Minor
Planet Center, which serves as the ultimate clearinghouse for data and names
of asteroids and other small objects in the solar system. Marsden said
scientists' ability to properly deal with early asteroid
data has not improved since 1998, and the problem stems from how information
is communicated.

"This is not to say that NEODyS, or any other professionals working in the
area, is doing bad science," Marsden said in comments today on a newsletter
called CCNet, which provides a forum for discussing asteroid hazards. "It is
very clear, however, that our community continues to
flounder in the way such information is made public."

Marsden was particularly critical of the fact that after the risk was found
to be nil, a "risk page" about the asteroid was removed from the NEODyS
site, rather than being updated to reflect the change.

"Illogical though it may seem to us, some people tend to assume that such
removal means that the object has in fact become more dangerous, not less,
and that the astronomers are involved in a cover-up," Marsden said. "A
simple posting to confirm that the object is no longer dangerous would work
wonders."

Benny Peiser, a researcher at Liverpool John Moores University and the
moderator of CCNet, said, "I wonder how many more asteroid scares it will
take before the NEO community will heed the recurring calls for adjustment
and make a determined effort to resolve this thorny issue."

Efforts have been made.

In 1999, the NEO community developed the Torino scale, a hazard index
structured something like the Richter Scale for earthquake magnitude. The
Torino scale was intended to improve definitions and communications between
scientists, as well as their ability to communicate potential
threats to the press and the public.

But so far the Torino scale has been nearly nonexistent as far as the public
is concerned.

The threat

According to scientists at NASA's Jet Propulsion Laboratory, there are
currently 315 known "potentially hazardous asteroids," or PHAs. Each appears
to be on a course that will one day bring it close to Earth's orbit, but
scientists stress that none of them are known to be on a
collision course with the planet.

Many other asteroids that might be listed as PHAs are thought to be out
there but not yet found.

An asteroid capable of global disaster would have to be more than a
quarter-mile wide, researchers say. Asteroids that large strike Earth only
once every 1,000 centuries on average, according to NASA officials. Other
estimates range widely, reflecting the fact that researchers don't know how
many asteroids are out there, let alone how many might eventually cross the
path of Earth.

Smaller asteroids that are believed to strike Earth every 1,000 to 10,000
years could destroy a city or cause devastating tsunamis. Scientists have in
recent years called on governments to begin making plans for how to defend
the planet against such impacts.

Copyright 2001, Space.com

============
(4) IT CAME FROM OUTER SPACE: BRITISH NEO-CATASTROPHISM

>From International Herald Tribune, 23 August 2001
http://www.iht.com/articles/30113.html

Barry James
International Herald Tribune 

PARIS. They're called catastrophists, a group of British scientists who
question many of the aspects of Darwinian evolution and argue that life on
Earth and the geology of the planet have been constantly reshaped by
asteroid strikes and other external shocks.

The latest sally from the catastrophist camp comes from the astronomer and
mathematician Chandra Wickramasinghe, who told a scientific congress in
California in July that he had found microbes in air samples scooped up by a
balloon flying 25 miles (about 40 kilometers) above the Earth's surface.

Mr. Wickramasinghe, director of the department of Astrobiology at Cardiff
University in Wales, said it was the first positive identification of
extraterrestrial microbial life outside the atmosphere. The fact that a
major British university has set up a department dedicated to a theory still
regarded with much skepticism and hostility in the academic community is one
indication of how accepted catastrophist ideas have become in British
science.

There is no school of catastrophists as such in Britain. They are a loosely
linked community of scientists drawn together by the gravitational pull of
common interests, and who occasionally work together on joint projects or
books. "There is no sense in which we come together to push a common view,"
said Mark Bailey, an astronomer who is director of the Observatory at Armagh
in Northern Ireland, now a center for catastrophist thinking. "We are really
individuals," he continued, "although most of us have worked together in
different combinations, so in that sense we get on well with one another."

Catastrophism has never had much of a following in the United States, partly
because of the debate between creationists and evolutionists, and partly
because of the cultish influence of Immanuel Velikovsky, a pseudo-scientist
who believed ancient myths could be explained by a near collision between
Venus and Earth.

Because of the impact of the Velikovsky affair in America, "it is very hard
for practicing scientists there to embrace the concept that catastrophism is
really an ongoing process," Mr. Bailey said. On the other hand, the Society
for Interdisciplinary Studies in Britain, which Mr. Bailey described as "a
broad church," includes some Velikovskians.

Mr. Wickramasinghe and his mentor, the astronomer Fred Hoyle, have long
argued that diseases like influenza that strike suddenly and simultaneously
at many places around the Earth arrive here from space. They say that
bombardment by external viruses or bacteria is a more logical explanation of
life on Earth than the Darwinian view that micro-organisms evolved into
higher life forms by constant replication and evolution.

While the Venus theory has been dismissed, two other British astronomers,
Victor Clube and Bill Napier, developed the theory that the Earth is
orbiting in the tail of a giant destroyed comet, and is under constant
bombardment by bits of cometary debris, ranging from dust to sizable rocks.
Occasionally, they say, it is hit by a particularly large chunk of rock,
like the asteroid that fell in Siberia in 1908, or possibly a huge body that
resulted in the extinction of the dinosaurs.

A leading astronomer of the last century, Ernst Opik of Estonia, who was the
first scientist to compute the collision probabilities of comets and
asteroids against planets, worked at Armagh from the 1940s to the 1980s. His
grandson, Lembit Opik, a member of Parliament, successfully helped lead the
scientific campaign that led the British government to set up the official
Task Force on Potentially Hazardous Near Earth Objects.

Another leading catastrophist is Mike Baillie, an expert in early climate
change, at Queen's University in Belfast. Mr. Baillie starts from scientific
grounds, such as the measurement of tree rings and the examination of ice
core samples, and then delves into mythology to find out if legends can
throw light on the extraordinary, perhaps catastrophic climatic events
revealed by the records. In a book, "Exodus to Arthur," Mr. Baillie asks
whether the simultaneous emergence of legends about dragons in China and
angels in Western mythology were common reactions to the appearance of a
comet.

Mr. Baillie points out that contemporary accounts at the time of the Black
Death, which killed one third of Europe's population in the 14th century,
mentioned droughts, floods, masses of dead fish, earthquakes, sheets of
fire, stinking smoke, huge hailstones and blasts of hot wind - all possible
descriptions, he said, of a close encounter with an asteroid or comet.

One record spoke of a large bright star over Paris, and another said that
the sky looked yellow and the air red because of burning vapors. Tree ring
studies reveal evidence of massive climate disturbance at the same time, Mr.
Baillie added.

Catastrophism began receiving a fairer hearing in the 1980s after Walter and
Luis Alvarez published an article in Science proposing that the extinction
of the dinosaurs had been caused by the impact of an asteroid about six
miles in diameter.

This was later linked to the crater, about 110 miles in diameter, identified
in 1990 at Chicxulub in the Yucatan Peninsula of Mexico. About 130 such
craters have now been identified on Earth. In 1994, scientists watched at
least 21 large fragments from the Shoemaker-Levy 9 comet plunge into the
surface of Jupiter, throwing up fireballs as big as the Earth. That, and a
mass of research culled from space observation, lends some credence to the
catastrophist view that a future disastrous impact on Earth is not a
question of if, but when.

Copyright 2001, The International Herald Tribune

================
(5) PROFESSOR SIR FRED HOYLE

The Guardian, 23 August 2001
http://www.guardian.co.uk/obituaries/story/0,3604,540961,00.html

Always a controversial astronomer, he rejected 'big bang' theory, turned his
back on Cambridge and was mysteriously denied a Nobel prize

Bernard Lovell
Thursday August 23, 2001
The Guardian

Fred Hoyle, who has died aged 86, will be remembered as one of the most
distinguished and controversial scientists of the 20th century. Soon after
the end of the second world war he became widely known both by scientists
and the public as one of the originators of a new theory of the universe. He
was a fluent writer and speaker and became the main expositor of this new
theory of the steady state, or continuous creation, according to which the
universe had existed for an infinite past time and would continue infinitely
into the future, as opposed to what Hoyle styled the "big bang" theory.

As a young man during the second world war, Hoyle had worked in the
Admiralty Signals Establishment and during that period he became friendly
with Hermann Bondi and Thomas Gold. The ideas that led to the continuous
creation theory were born at that time and in 1948 their historic papers on
the theory were published. Although the names of Bondi, Hoyle and Gold are
associated with that revolutionary theory, Hoyle's paper was published
separately, two months later than the joint one of Bondi and Gold. The
latter had stressed the philosophical aspect of a perfect cosmological
principle in which the universe would have a high degree of uniformity not
only in space but also in time, thereby evading the scientific problem
associated with a beginning in a finite past time. Hoyle dealt with the
continuous creation of the primordial hydrogen that would be essential to
maintain the steady state, and placed the concept within the framework of
general relativity.

The detailed presentation of the theory in the journal of the Royal
Astronomical Society in 1948 was not a cooperative effort. The evidence is
that Hoyle had sent his paper to an American journal, where it was rejected.
Its eventual publication, two months after the Bondi-Gold paper, was a
coincidence that formed an impenetrable phalanx for nearly two decades. The
conflict with the conventional idea that the universe had a specific origin
billions of years in time past was absolute. Until the discovery of the
cosmic microwave background in 1965, the observational evidence was
inconclusive and the emotive feelings aroused led to one of the bitterest
scientific divisions of the century. Hoyle never accepted the complete
defeat of the continuous creation theory, and long after the "big bang"
universe had become conventional scientific wisdom he continued to probe its
defects.

Although Hoyle was most widely known for this cosmological theory, there is
little doubt that his most lasting and significant contribution to science
concerns the origin of the elements. This theory of nucleogenesis (the
build-up of the elements in the hot interiors of stars) was an outstanding
scientific landmark of the 1950s. In the development of this theory Hoyle
collaborated with WA Fowler of the California Institute of Technology in
Pasadena, and with Geoffrey and Margaret Burbidge.

Hitherto, the general belief was that all the elements must have been
produced in the hot primordial universe. The new paper, on the contrary,
showed that the elements could be produced from the primordial hydrogen by
nucleo-synthesis in the hot interior of stars. The theory gave a
satisfactory account of the relative abundances of the elements, provided an
explanation of the direction of stellar evolution and gave an objective
basis for calculation of the internal constitution of stars.

The theory also confirmed a prediction of Hoyle's that there must be an
excited state of the carbon twelve isotope - at the energy he had predicted
from a consideration of the evolution of red giant stars. This,
incidentally, was agreeably consistent with the steady state cosmological
theory, since there was no necessity for an initial hot condition of a
primordial universe.

The paper, published in an American journal in 1957, has been described as
monumental, and the theory has had a cardinal influence on astrophysics.
Although there were four authors, it is widely known that the Burbidges
contributed the data from their stellar observations and that the core and
essence of the paper was the work of Fowler and Hoyle.

Fowler was awarded the Nobel prize for physics in 1983, and why Hoyle was
not included in this award remains a mystery hidden in the confidential
documents of the Royal Swedish Academy. The editor of the scientific journal
Nature suggested that the academy did not wish to be associated with any
endorsement of another idea then being promulgated by Hoyle. This was linked
to Hoyle's belief that life must be of frequent occurrence in the universe.
He argued that the primeval molecules from which life evolved on Earth had
been transported from elsewhere in the universe. In itself this idea would
not necessarily be rejected as absurd by the scientific community, but Hoyle
had publicised a further argument that influenza epidemics were associated
with the passage of the Earth through certain meteor streams, the particles
of which conveyed the virus to Earth.

This was dismissed as fictional by nearly all members of the biological and
physical scientific disciplines. Indeed, the idea belonged more to Hoyle's
activity as a writer of science fiction for over three decades. His most
famous novel was October The First Is Too Late, and several others, such as
The Black Cloud (1957) and A For Andromeda (1962), which was made into a
television serial, achieved a wide circulation. Another, Rockets In Ursa
Major (1962), was also produced as a play.

Hoyle played a prominent part in the scientific affairs of the UK. He served
on the council of the Royal Society as vice president from 1969 to 1971 and
was president of the Royal Astronomical Society 1971-73. As a member of the
Science Research Council from 1967 to 1972 he was active in the assessment
of the astronomical facilities in the southern hemisphere, which led to the
creation of the 150-inch Anglo-Australian telescope at Siding Spring in New
South Wales. He was a member of the joint policy committee from 1967, during
the planning stage for the telescope, and became chairman of the
Anglo-Australian telescope board in 1973, and presided at the inauguration
of the telescope in 1974 by the Prince of Wales.

Hoyle was born at Bingley in Yorkshire, the son of a wool merchant, and by
the age of 10 could navigate by the stars. From Bingley grammar school he
went up to Emmanuel College, Cambridge, to read maths: he was the Mayhew
Prizeman in the 1936 Cambridge Mathematical Tripos. In his immediate
postgraduate years he was Smith's Prizeman, Goldsmith Exhibitioner and was
awarded a senior exhibition by the Commission for the Exhibition of 1851. He
was elected to a fellowship at St John's in 1939.

During these years he first became associated with RA Lyttleton on problems
of accretion of dust and gas around large bodies. Thereby began his shift of
interest from mathematical physics to astronomy and, in later years, led to
his work on the formation of planetary systems and to his conviction that
life must be of frequent occurrence in the universe. In a broadcast talk in
the early 50s, at a time when Australia was dominating England at cricket,
he remarked that he would wager that somewhere in the Milky Way there was a
cricket team who could beat the Australians.

During the war he was engaged in technical projects, such as radar for the
Admiralty, where he found himself working with Bondi and Gold. Hoyle
returned to Cambridge after the war as university lecturer in mathematics.
In 1958 he was appointed the Plumian professor of astronomy and became the
first director of the Cambridge Institute of Theoretical Astronomy in 1967.

Although the occupant of two such distinguished offices, he became immensely
unhappy with his life in Cambridge. The crisis came over a dispute
concerning the election to a professorial chair and he tendered his
resignation as Plumian professor from 1972 and as director of the institute
from 1973.

For many years I had been closely associated with Hoyle in astronomical and
policy matters and his attitude to Cambridge was epitomised in his
explanatory letter to me.

"I do not see any sense in continuing to skirmish on a battlefield where I
can never hope to win. The Cambridge system is effectively designed to
prevent one ever establishing a directed policy - key decisions can be upset
by ill-informed and politically motivated committees. To be effective in
this system one must for ever be watching one's colleagues, almost like a
Robespierre spy system. If one does so, then of course little time is left
for any real science."

At the age of 57, Hoyle retired from his formal appointments in the UK,
residing first in the Lake District and then on the south coast. He held
honorary research professorships at the University of Manchester and
University College, Cardiff, from which he published extensively with NC
Wickramasinghe on the biological aspects of his astronomical concepts. He
did much of his work in the United States, particularly in the California
Institute of Technology, where he was appointed visiting associate in
physics in 1963, and at Cornell, where he held a visiting professorship for
six years after he retired from Cambridge.

Hoyle was awarded numerous honorary doctorates, medals and prizes. His many
books included Frontiers of Astronomy (1955), Men And Materialism(1956),
Star Formation (1963), Galaxies, Nuclei and Quasars (1965), The Relation Of
Physics And Cosmology (1973), Ten Faces Of The Universe (1977) and On
Stonehenge (1977). His autobiography, Home Is Where The Wind Blows, was
published in 1994.

He was elected a fellow of the Royal Society in 1957 and was knighted in
1972. In 1974 he was awarded the royal medal of the Royal Society, and on
that occasion the president said that Hoyle was one of the most original
minds in present-day astronomy and that his "enormous output of ideas are
immediately recognised as challenging to astronomers generally... his
popularisation of astronomical science can be warmly commended for the
descriptive style used and the feeling of enthusiasm about his subject which
they succeed in conveying".

Indeed, Hoyle packed the lecture rooms wherever he spoke in the world, and
"according to Hoyle" was a frequent catchphrase of the second half of the
20th century.

He is survived by his wife, Barbara Clark, whom he married in 1939, and by
his son and daughter.

* Fred Hoyle, astronomer and writer, born June 24 1915; died August 20 2001

Copyright 2001, The Guardian

===============
(6) BIG ENOUGH TO BURY DARWIN

>From The Guardian 23 August 2001
http://education.guardian.co.uk/higher/physicalscience/story/0,9836,541468,00.html

Lee Elliot Major looks at the theories that secured Sir Fred Hoyle's
reputation as one of the 20th century's leading scientists

Thursday August 23, 2001
 
Professor Fred Hoyle
 
Three ground-breaking scientific debates played a part in securing the
reputation of Sir Fred Hoyle, who died this week aged 86, as one of the
founding fathers of cosmology, the most creative astrophysicist of his time,
and the greatest scientific rebel of the late 20th century.

The formation of stars

Dr Hoyle helped to solve a problem that had dogged physicists for years: how
do stars create heavier elements, such as carbon, nitrogen and oxygen? A sun
derives its power from the fusion of basic elements. But it was only when
Hoyle's identified the final link - a special state of carbon-12 - that the
full chain reaction could be understood. One of Hoyle's collaborators
received a Nobel Prize for their work.

The big bang theory

Hoyle coined the phrase 'big bang' to ridicule the theory that the cosmos
was created by a huge explosion 12bn years ago. Yet the phrase helped to
popularise the theory, assuming universal status among the very scientists
arguing the ripples of the great explosion can still be observed in a slowly
expanding universe today.

Hoyle's rival theory is that the universe exists in a steady state. It
contends that matter is constantly being created, so the expanding universe
remains roughly the same at all times, with no beginning or end. Few
scientists support Hoyle's steady state model.

Life originated from outer space

Even more controversial than Hoyle's cosmological theories, was his
contention that life did not evolve according to Darwin's theory of natural
selection, but was created from micro-organisms or biochemical compounds
from outer space. 'Panspermia' is based on the idea that mutating life-forms
continually fall from space.

Nor did Hoyle think this was a random process. He argued it was the
handiwork of a super-intelligent civilisation wishing to "seed" planet
Earth. Hoyle's research also attributed the onset of various epidemics to
interstellar viruses, drawing connections between asteroids and flu
outbreaks at schools in remote parts of England and Wales.

Hoyle's belief in a cosmic super-intelligence also surfaced during his
successful career as a science fiction writer. In his 1962 novel, A for
Andromeda, radio instructions were sent by aliens telling humans how to
build an all-powerful and destructive machine. The book was developed into a
BBC television series, starring Julie Christie.

Hoyleisms: A selection of quotes from the great man:

* "Space isn't remote at all. It's only an hour's drive away if your car
could go straight upwards."

*"There is a coherent plan in the universe, though I don't know what it's a
plan for."

*"I don't see the logic of rejecting data just because they seem
incredible."

*"The likelihood of the formation of life from inanimate matter is one to a
number with 40,000 naughts after is... It is big enough to bury Darwin and
the whole theory of evolution. There was no primeval soup, neither on this
planet nor any other, and if the beginnings of life were not random, they
must therefore have been the product of purposeful intelligence."

*"Once we see, however, that the probability of life originating at random
is so utterly minuscule as to make the random concept absurd, it becomes
sensible to think that the favourable properties of physics, on which life
depends, are in every respect deliberate... It is, therefore, almost
inevitable that our own measure of intelligence must reflect higher
intelligence - even to the extreme idealized limit of God."

*"The popular news media were back on the job now. Displaying to the full
their twin characteristics, incredible persistence and the incredible
inability to see the point, they clamored for an answer to the absurd
question: Could Martian computers be said to be really alive? [from Hoyle's
novel, Element 79]

Copyright 2001, The Guardian

=============
(7) WELL PRESERVED METEORITE YIELDS CLUES TO CARBON EVOLUTION IN SPACE

>From Andrew Yee <ayee@nova.astro.utoronto.ca>

Arizona State University

Contact:
James Hathaway, (480) 965-6375, Hathaway@asu.edu

Source:
Sandra Pizzarello, 480-965-3370, pizar@asu.edu

Embargoed until 2 p.m. EST, August 23, 2001

Well Preserved Meteorite Yields Clues to Carbon Evolution in Space

The first results are in from the organic analysis of the Tagish Lake
Meteorite, a rare, carbon-rich meteorite classified as a "carbonaceous
chondrite" that fell on a frozen Canadian lake in January 2000 and is the
most pristine specimen ever studied of this group of important space
objects. Carbonaceous chondrite meteorites contain vital clues to the
evolution of carbon compounds in our solar system preceding the origin of
life.

The analysis, conducted by a team headed by chemist Sandra Pizzarello, a
research scientist at Arizona State University, on 4.5 grams taken from the
sealed interior of the meteorite, found organic compounds in the meteorite
with some similarities to other known carbonaceous chondrites, but also
clear differences -- most notably the near-absence of the amino acids found
in some meteorites studied before.

In an article scheduled to appear in the August 24 issue of the online
journal Science Express
(http://www.sciencemag.org/cgi/content/abstract/1062614v1 , with publication
in Science to follow) the team notes that the chemistry of the Tagish Lake
Meteorite appears to preserve organics that accumulated or developed in the
early history of the Solar System -- including molecular bubbles of carbon
(fullerenes or "buckyballs") containing the noble gasses helium and argon in
a ratio similar to the gas and dust cloud that formed the planets -- and
thus perhaps reflects an early stage in a process of evolution of complex
carbon compounds in space.

"The chemistry here is different from that we have seen in any other
meteorite," said Pizzarello. "It's simple, when compared with Murchison (a
famous carbon meteorite found in Australia in 1969 that contained numerous
amino acids and a variety of other organic compounds) and probably
represents a separate line of chemical evolution. However, it still includes
compounds that are identical to biomolecules."

Other members of the research team include Yongsong Huang from the
Department of Geological Sciences at Brown University; Luann Becker from the
Institute for Crustal Studies at the University of California Santa Barbara;
Robert J. Poreda from the Department of Earth and Environmental Sciences,
University of Rochester; George Cooper from the NASA Ames Research Center;
and Ronald A. Nieman and Michael Williams, both also from ASU.

The Science paper notes that many of the organic compounds found in the
Tagish Lake sample have also been found in other meteorites, but that the
distribution of compounds is different, particularly for the amino acids and
carboxylic acids.

"Some people have been disappointed that we found virtually no amino acids,
but scientifically this is very exciting," Pizzarello said. "This meteorite
shows the complexity of the history of organic compounds in space -- it
seems to have had a distinct evolution.

"We found some compounds identical to some in Murchison that show the same
'interstellar connection' in their abundance of deuterium (heavy hydrogen),
while some others differ from Murchison in amounts and variety," said
Pizzarello, meaning that for some groups of organic molecules, only the
simplest species were found in Tagish Lake, as opposed to a broader
distribution of species found in Murchison. "Overall, Tagish Lake represents
a simpler, more unaltered stage than we have seen before."

What emerges from the analysis is evidence for what Pizzarello calls "a
different outcome" of organic chemical evolution in space likely to have
happened during the formation and development of the solar system, "but one
that still might have contributed molecular precursors of biomolecules to
the origins of life," she noted.

============
OUR SOLAR SYSTEM'S OLDEST RAW MATERIALS

News Service
Brown University
Providence, Rhode Island

News Service Contact:
Janet Kerlin, Science@brown.edu

For Immediate Release: August 23, 2001

Our solar system's oldest raw materials

Brown scientists identify Tagish Lake meteorite's origin in space

PROVIDENCE, R.I. -- Brown geologists Takahiro Hiroi and Carle Pieters and a
colleague from NASA have identified the location from which an unusually
well-preserved meteorite fell -- the mid-to-far end of the asteroid belt
between Mars and Jupiter. Their results confirm that the Tagish Lake
meteorite is made of probably the oldest materials in the solar system.

To the amazement of observers, the fireball fell in northern British
Columbia in January 2000. The event was photographed, recorded by
satellites, and resulted in hundreds of fragments being collected from a
frozen lake. The meteorite was probably the size of van, but broke into
fragments that were preserved in ice from the lake.

Hiroi, Pieters and Michael Zolensky of NASA's Johnson Space Center in
Houston are the first to identify the carbon-rich meteorite as having broken
off from a D-type asteroid, the kind that most scientists acknowledge
contains the oldest raw materials among asteroids. Their results were
published by the journal Science, within the "Science Express" Web site, on
Aug. 23, 2001
[ http://www.sciencemag.org/cgi/content/abstract/1063734v1 ].

Their method, reflectance spectroscopy, provides an optical fingerprint
showing a meteorite's composition. Data is obtained by measuring the amount
of reflected light as wavelength is changed from visible to near-infrared.

Their study provides clues in determining the formation of the solar system
4.6 billion years ago. The research was funded by grants from NASA.

A second article on the "Science Express" Web site details the organic
content of the Tagish Lake meteorite. Brown assistant professor Yongsong
Huang is a co-author with lead investigator Sandra Pizzarello of the Arizona
State University Chemistry Department.

At Brown, the researchers used state-of-the art technology to measure the
isotopic composition of individual compounds. The findings provide insight
to an outcome of early solar chemical evolution that differs from any seen
in meteorites so far.

==============
(8) MINING ASTEROIDS

>From IEEE SPECTRUM Online, 23 August 2001

http://www.spectrum.ieee.org/WEBONLY/publicfeature/aug01/aster.html

Melting trapped ice could turn a profit for private companies, with metal
processing not far behind

By Mark Ingebretsen, Contributing Editor

One day this century an unmanned space probe will touch down on a dormant
comet. The probe will drill through the comet's gravel-like shell to reach
the ice beneath. Next, a tube will descend into the drilled hole, and, using
heat from solar mirrors, will slowly melt the ice, pumping the melt into a
giant balloon-like tank. As the tank fills, the water in it will freeze once
again. Some of the water will be diverted into the probe, where it will be
heated later, again by means of solar energy. The resulting steam will be
used to supply the thrust needed for the probe's return to Earth orbit [see
diagram].

Arriving there months later, the probe's icy cargo might be used to
steam-power a follow-up mission or to supply drinking water to orbital
outposts like the Alpha Space Station. Or it might be used to form a frozen
ring to shield those outposts from harmful radiation.

True, a steam-belching rocket ferrying a balloon full of ice through space
isn't as exciting as a manned expedition to Mars. Nonetheless, a fledgling
group of researchers believes a mission similar to the one described here is
not only possible using present-day technology, but could make money for its
organizers.

Indeed, a veritable El Dorado awaits in the so-called near Earth objects
(NEOs) within the solar system. The term NEO refers to both dormant comets
(comets that no longer produce distinctive tails) and asteroids that travel
about the sun, often in highly elliptical orbits. Unlike the space rubble
that lies in the Asteroid Belt between Mars and Jupiter, the NEOs' orbits
occasionally bring them quite close to Earth, some even to the point of
impact [see diagram].

Astronomers have catalogued many types of NEOs. The dormant-comet variety
contains mostly water mixed in with bits of sand and loose rock. Other NEOs,
called C types, are a rough mixture of volatiles (made up of clays, hydrated
salts, and water), plus silicates along with metals like iron, nickel, and
platinum.

John Lewis, who co-directs the Space Engineering Research Center at the
University of Arizona at Tucson, studied one C-type asteroid, a 2-km-wide
NEO called Amun. He concluded that the monetary value of Amun's platinum
group metals (pgms)-platinum, iridium, osmium, palladium, and so on-is more
than US $6 trillion. Amun's iron and nickel might be worth something on the
order of $8 trillion. Add another $6 trillion for Amun's cobalt deposits,
and the asteroid's value totals a spectacular $20 trillion!

To get at these valuable resources, Amun's metallic ores would need to be
separated out from the asteroid's silicates and volatiles. But another kind
of asteroid, the M-type, is almost pure metal, mostly iron. Some M-types,
like the unassumingly named 1986 DA, are mountain-sized blends of iron,
nickel, and cobalt-in other words, naturally occurring stainless steel. In
all, roughly 2000 NEOs about the size of 1986 DA are known to exist, with as
many as 50 more being discovered each year.

Gravity's rainbow

NEOs came to the public's attention last February, when NASA's Near Earth
Asteroid Rendezvous probe made a controlled landing on the asteroid Eros.
But researchers have pondered for decades ways that asteroids might be
profitably mined. Their interest has everything to do with gravity. Because
of the negligible gravity of NEOs, sending a probe to reach one takes less
energy than a visit to any other celestial body, including the moon.

In space, a mass continues in motion forever unless it collides with
something. In navigating among orbiting bodies in space, the primary measure
of how hard it is to get from point A to point B becomes not distance but a
quantity called delta-V (DV). Escaping one planet's gravity, adjusting orbit
so as to synchronize the time of arrival with the destination's own path
through space, and finally slowing enough to land gently or enter orbit upon
arrival-all require considerable changes in velocity, or DV.

The amount of energy required to travel between destination points (and
hence how much fuel must be carried) increases with the total DV and the
mass of the spacecraft. The DV needed to ascend to low Earth orbit (LEO) is
a crippling 9 km/s or so-most of the mass of a rocket has to be fuel and
engines, not payload. But as science fiction writer Robert Heinlein noted,
after you reach Earth orbit, you're halfway to anywhere. That's because a
rocket, sitting on a launch pad, is considered to have zero velocity.
(Strictly speaking, the earth's rotation makes a difference: a rocket
launched at the equator in the direction of that rotation has an initial
velocity advantage over one launched at a higher latitude in the same
direction.)

But once the rocket is in LEO, the additional increases in velocity needed
to reach many destinations in the solar system are smaller-and hence the
energy required is less, too [see graph]. To go another 340 000 km from LEO
and land gently on the moon, for instance, requires an additional velocity
change of a little over 6 km/s. But a voyage from Earth orbit to an NEO
would require only 5 km/s, possibly even less than 4.3 km/s, depending on
the asteroid's size and trajectory in relation to Earth.

Even greater reductions in DV could be achieved on return trips from NEOs.
Lifting off the lunar surface and traveling to Earth orbit would take a DV
of 3 km/s, assuming Earth's atmosphere is used for aerobraking. In contrast,
a trip from an asteroid would require just 1 km/s or less, because many NEOs
possess negligible gravity, so hardly any energy is required to lift objects
off their surfaces. This DV difference between NEOs and the moon for the
return trip is important, since it is during that portion of the trip that
the probe would carry its bulky cargo of ores.

Any reduction in required velocity, of course, translates directly into
rocket fuel savings. In addition, many asteroids are thought to be richer in
metals and volatiles than the lunar surface. All told, mining NEOs would
take less energy and time and so yield a higher return than would be the
case with the moon.

Big science

With these facts in mind, elaborate plans have been drawn up for NEO
missions. In a typical plan, a ship departs Earth for an asteroid when the
two bodies' orbits are such that the lowest DV is required. Mining
operations might last many months, and meanwhile, Earth and the NEO would be
moving farther and farther apart. When the two orbits coincided once again,
the mined materials could be shipped back to Earth.

As with most, if not all, speculative space ventures, debate has raged over
whether these missions should be manned or robotic [see "Modes of Mining in
Orbit"]. But early blueprints of NEO mining missions put human crews
squarely at the helm.

One of the first detailed plans for an asteroid mission emerged in 1977, as
part of a NASA study on space colonization. The plan, co-authored by
space-futurist Brian O'Leary, came soon after the huge expenditures of the
Apollo program. Accordingly, it employed a philosophy of striking with
overwhelming force.

O'Leary's task force was charged with devising ways to retrieve raw
materials from an NEO. The group's solution was to send a large crew of
astronaut-miners to a C-type asteroid. Over the course of their three-year
mission, volatiles would be baked out of the rock, using a 600 °C solar
furnace. The volatiles, which would include water and potential
fuel-producing substances such as nitrogen, carbon, sulfur, and phosphorus,
would supply the fuel needed to separate out the asteroid's metals and other
materials, which would be catapulted back to LEO for further processing.

The study determined that to retrieve half the mass of a million-metric-ton
asteroid, some 10 000 metric tons of materials would need to be lifted into
LEO at an assumed cost of $240/kg (1977 dollars). The total cost of the
mission was put at $31 billion, including R&D costs. To ship the same
quantity of mined materials from Earth's surface would cost a prohibitive
$663 billion.

Islands of ice

In 1993, perhaps to accommodate diminished expectations in space, Lewis, of
the University of Arizona, published a similar study that examined the cost
of mining fuels and other materials on the moon, versus mining them on NEOs.
For starters, Lewis reasoned that the lunar mission could use as fuel for
its return trip hydrogen from the ice supposed to exist at the lunar poles.
The resulting payback after 10 lunar missions would be 8:1. That is, eight
times more fuel could be transported than consumed. His calculations
included the amount of fuel needed to send the vessel to the moon so that
fuel recovery operations could begin.

When Lewis looked at NEOs as a source of water and fuel, the potential
payback improved considerably. He estimated that an NEO mission could return
three times as much fuel or water as it consumed in making the
voyage&#151;and that was just for the first trip and after factoring in the
fuel cost of getting the probe to the asteroid to be refueled for the return
voyage.

If the ship could be reused five times, the payback ratio would rise to
15:1. "Each trip makes considerable masses of propellant available for other
uses in near Earth space," Lewis wrote.

But the actual distances must be taken into account; if many round trips
from the moon to LEO can be made in the same time as one round trip from an
NEO to Earth orbit, lunar mining will still prove to be the most economical.
This constraint indicates a need for an approach to NEO mining with
continuous operations and multiple transport ships, increasing start-up
costs.

Many researchers agree with the choice of water as the likely first target
of an NEO mining mission. "Water is peculiarly easy to handle and peculiarly
useful," said Mark Sonter, a mining engineer based in Sydney, Australia, who
has written several papers on profitable ways to mine NEOs. "You're almost
guaranteed 10-30 percent recoverable water from water-bearing asteroids," he
said. "Once you've extracted it at the asteroid, you can use it directly as
propellant in a steam rocket or you can split it into hydrogen and oxygen
and use it in a classic chemical rocket, and using some of it, you can
return the rest to Earth orbit, where it can be used as propellant, as life
support, or as radiation shielding."

A market for water already exists in LEO, believes Kevin Reed, a research
scientist for the aerospace-defense firm BAE Systems, Farnborough, UK. Like
Sonter and many another NEO mining enthusiast, Reed earns a living at an
unrelated day job, but spends much of his free time devising ways to profit
from asteroid mining. The market for water, he said, is the Alpha Space
Station, which currently gets its water as a byproduct of visiting space
shuttles' fuel cells. As the station grows, so will its need for
consumables. "You could sell [Alpha] water and oxygen," he says. And in the
future, "If the Russians got the capability of supplying water and oxygen to
a Mir 2, they could take up as many [space tourists like] Denis Tito as they
want."

All that glitters

But why bother ferrying water around instead of mining metals and returning
them to Earth's surface-especially since trillions of dollars worth of
high-valued metals are ripe for the taking?

The fact is that transporting materials back to Earth changes the economics
of the equation. For starters, the logistical problems greatly increase.
"One of the things that we're discovering is just how fragile atmospheric
physics is," said Richard Gertsch, an assistant professor in the mining and
materials engineering department at Michigan Technological University,
Houghton. Thus, any miscalculation could turn an ore-bearing shuttle into a
hailstorm of molten metal. Disasters aside, developing a craft that
transports materials back to Earth as efficiently as ships and rail cars now
transport ores from terrestrial mines is a tall order.

An even bigger problem from an economic standpoint is that asteroidal
supplies of iron may easily exceed demand, depressing prices. A huge influx
of space metals-or even the expectation that they might come onto the
market-would result in a price collapse. Also, any venture aimed at
returning these materials from space has to compete with the highly
efficient terrestrial mining techniques already in use.

Still, given that asteroids contain platinum metals worth trillions, why
isn't it possible to profitably return these to earth? "The whole idea of
space resources is that the resources are huge. How you use them has been
the real problem," Gertsch laments. "Everyone goes back to high-value
metals, the pgms."

Vexed by the problem, Gertsch co-wrote a study with his wife Leslie, another
assistant professor at Michigan Technological University with a special
interest in asteroid mining. They envisioned a project equivalent in scale
to the Anglo-French Channel Tunnel. It would cost at least $5 billion and
take up to 12 years to finish. The study assumed that the asteroid mined
would be made up of 150 parts per million of pgms, a concentration thought
to occur in about one in 10 platinum-bearing asteroids.

Finding a suitable asteroid and mounting a mission would consume up to four
years of the project, the Gertsches reasoned. On arrival, miners would need
to sift through 500 million metric tons of material in order to extract
enough platinum-some 68 thousand metric tons, at an assumed price of about
$13 per gram-to generate a return of 100 percent on the project.

However, even a 100 percent return rate would not attract the needed
billions in risk capital, given the 12-year timetable and the high
probability of failure, the Gertsches concluded.

Space is the place

Another proponent of expeditions to the asteroids is Jim Benson, chief
executive officer of a publicly traded company called SpaceDev, in Poway,
Calif. At a meeting he attended with a prominent venture capitalist, "I was
told they wouldn't consider plans in which they would only make 100 times
their money," Benson said. "Unless they were going to make 1000 times their
money, they're not even interested."

For this reason, researchers have tried to promote the idea of mining
materials in space for use in orbit. "I don't think these resources need to
be brought back," Benson said. Since it costs $10 000/kg to lift anything
into space, any material in orbit already has a putative value of $10 000,
he explained. His company hopes to raise the $12 million needed to set a
probe down on an asteroid, assay its resources, then legally claim it [see
artist's rendering]. Actual mining missions would come later.

Last November a group called the Space Resources Roundtable met to discuss
similar plans to bootstrap NEO mining operations. The group's members are
drawn from the space, mining, and financial communities and have been
meeting under the auspices of the Colorado School of Mines, in Golden, since
1999. The roundtable bases its ideas on the thinking of Lewis and others
that NEO mining can be launched cheaply and multiple missions can be
undertaken. The end result should be an increasingly valuable bank of water
or other materials in LEO.

Another strategy is offered by Brad Blair, a former mining company engineer
and now a doctoral candidate at the Colorado School of Mines. He proposes
turning the second stages of commercial launch rockets into transports for
space miners and their equipment to NEOs. Once depleted, these stages are
normally allowed to burn up in the atmosphere, but Blair claims they could
be modified to run on steam.

Beyond this horizon

How long before any of this begins to happen? Many cite 20 years as a
realistic figure, especially if companies from the private sector lead the
way. "The problem is not the technology [but] companies' perceptions of what
the risks would be and their perceptions of how it would be received by the
investment community," said mining engineer Sonter.

But that may change as investors continue to search for the Next Big Thing.
"It's going to become increasingly obvious to people with money that this is
going to be the new Internet," said SpaceDev's Benson. His company has
allied with a Canadian nonprofit group called the Northern Center for
Advanced Technology Inc. in Sudbury, Ont., Canada. The group, in part,
represents mining interests from that region, and hopes to develop new
markets for local technological know-how as mines there gradually become
depleted. Ironically, those mines contain ores from an asteroid impact some
100 million years ago.

Stephen Cass, Editor

Copyright 2001, IEEE

============================
* LETTERS TO THE MODERATOR *
============================

(9) ASTEROID 2001 PM9

>From Carl Hergenrother <chergen@fortuna.lpl.arizona.edu>

The '2001 PM9' affair has again called into question the method by which
potential impactors are recognized and disseminated to the scientific
community and public at large. In a perfect world, every newly discovered
Near-Earth object (NEO) would be followed for months to years after
discovery in order to accurately predict any future impact events.
Unfortunately this perfect world does not exist. There are presently not
enough resources avaliable to adequately monitor all NEO discoveries,
especially when they are fainter than 20th magnitude. Due to this current
state of affairs, the limited observers who do the service of following NEOs
need to concentrate on those objects that are a threat. The announcements by
the Spaceguard Central Node (I didn't see the JPL one) do a good job of
informing the follow-up community of objects that are
urgently in need of observation and help focus attention on them. These
announcements, and the calculations by the Pisa and JPL programs that
precede them, have done their job and definitely focused attention.

The question at hand is what is the best way to get the word out and more
importantly, can we do better? If an object is recognized as a potential
impactor, further observations are needed in order to rule out an impact or
in the worst case, to better define when and where it will impact. A few
options are available, 1) persuade an observer to conduct future
observations, 2) to sit back and hope the object is observed during the
course of routine observations or 3) forget the
future and inform observers with access to past images to look for
pre-discovery observations. Option 2 is dangerous, in that one can never
guarantee that any object will be observed again. Many objects are followed
for only a short time and then lost. Losing an object may be due to it's
faintness, location in the sky, bad weather, etc. Even relatively bright
objects that are well in the range of the majority of observers can fall
through the cracks as observers concentrate on newer discoveries. 1998 OX4
and most of the objects that currently reside on the NEODyS 'Risk page' are
examples of objects that could have been better observed had their
importance been known at the time. Option 3 is one that can really make a
big difference in a short amount of time. Orbital arcs can be substantially
increased by the measurement of precovery observations. But option 3 also
doesn't guarantee a detection and can highly bias a computed orbit if there
are uncertainties in the measurement. 2000 SG344 is an example, a single
night of overweighted precovery observations from a year earlier led to its
announcement as an impact candidate. Further observations from that year
showed the object to be less of a hazard. Option 1, on the other hand, has a
much higher probability of producing further data since in most cases the
object is still visible. Longer discovery apparition arcs also insure a
greater chance of recovering the object at further apparitions.

When should observers be asked for further observations? Currently, it is
done as soon as a dangerous object is recognized. Sometimes, as in 2001 PM9,
2000 SG344, 2000 AN10, etc, observations which show an object to be harmless
are obtained in days or even hours of the announcement. If the initial
impact scenario has been reported in the press, the subsequent 'all clear'
does make our community look bad. A mistake was made, it's a cover-up, a
scheme to wrestle more funding from the government, and damn those
scientists for scaring us; these are all sentiments that have been published
in follow-up articles after an impact scenario has been eliminated. But does
that mean the announcement for further observations was flawed? It did it's
job, further observations did surface, observations that may not have been
made had the nature of the object in question not been broadcast to the
observers. Unless further observations are known to be forthcoming, the
impact announcement should be released immediately. A delay could result in
the losing of an object as it fades or as the moon brightens the sky. It's
never too early to study and prepare for a potential natural disaster.

One issue that hasn't been mentioned in previous statements on the subject
but may not be lurking too far below the surface, is the issue of who gets
notified when a potential impactor is found. Unless we allow the fates to
decide and sit back hoping the impactor is observed in the future, observers
with access to telescopes or past data must be notified. Should this
notification be limited to a few key observers in order to lessen the chance
of the impactor 'leaking' to the public? Though this course of action would
probably allow most impact scenarios to come and go behind close doors; is
the secrecy worth it? If word did leak out, news of a cover-up concerning
the potential end of the world would naturally occur, and the news wouldn't
be too far off the mark. Who would be trusted to conduct these observations
and what if they wanted to make their work public anyway? The important
thing is to obtain as much information on a problem object as soon as
possible; why limit the number of people who can help? Much of the current
follow-up of objects brighter than 19th magnitude are done by private
citizens and not professionals. To exclude this important resource would be
wasteful.

Contrary to the public's and even many researcher's preconceptions, our
ability to observe dangerous asteroids and comets is limited. Telescopes are
scheduled months in advance. One can not just simply waltz up to a
professional telescope and observe, even if it's a known potential
impactor. Other observers might be observing and many aren't concerned with
our area of study plus many times the instrumentation on the telescope that
night may not be suited for the observations. If observations are needed,
the word must be disseminated to the widest possible audience of potential
observers in a timely manner in order to insure that observation attempts
can be made. Notifing a subset of observers only increases the chance of
failure.

The main concern about the current state of NEO impector notification seems
to be less about it's scientific merit and more about the public's
perception of asteroid researchers. We are in a delicate position. We are
the front line of defense against a very rare yet very destructive
natural phenomenon. Chances are we will detect nothing that will do harm in
our lifetimes, or our children's, grandchildren's, etc. But search we must,
just in case. But as a result, most impact
warnings will be nothing but warnings, the probablity of impact falling to
zero. The average person has a hard time grasping the real meaning of
probabilities. If further observations prove that an object has a
probability of impact that is zero, that does not mean a previous prediction
with less data that showed a probability of impact of 1-in-100 was wrong or
a mistake. Whether we like it or not most of our warnings will be 'flase
alarms'. But is that a bad thing? People are used to 'erroneous' predictions
of natural disasters. Every time a tropical storm forms in the Atlantic, the
news is swamped with stories even if the storm has little chance of
landfall.

How many times has a hurricane been forecast to impact the east coast of the
US only to veer off to the northeast. The forecasters don't decide to hold
back all news of potential landfalling storm for 72 hours just to get it
right. Yes, 'flase alarms' will make the public more cynical about asteroid
predictions but some amount of that is expected and unavoidable due to the
uncertainty of the problem. If the day comes when a true impactor has been
found, some people will listen and some will be non-believers, whether they
are average people, government officials or even fellow scientists. People
may think asteroid scientists are often wrong but very few doubt that an
asteroid impact can happen. I believe people should be informed about what
we are doing and not kept in the dark. If the media wants to report our
actions, so be it. If the fringe wants to scream cover-up about roaming
Martian moons, that's their right. Our policies should not be entirely
dictated by the public's perception. It must be balanced by scientific
merit. An open policy of impactor announcements is the best way to insure
that the required work will get done by the most people. Scaring a few
people or making asteroid researchers look like clowns every now and then
may be the price we pay for insuring we don't go the way of the dinosaurs.
To steal the sentiment of Benjamin Franklin, this policy may not be the best
but it may be the best that we can do. Of course, if anyone has anything
better...

==========
(10) 2001 PM9: WE LUCKY FEW

>From Larry Robinson <lrobinsn@ix.netcom.com>

Dear Benny:

I realize at times it must seem like the astronomy community is disorganized
and alarmist, and perhaps it is. The fact of the matter is that there are
really very few people contributing to this effort and the need for data in
the event of initial suspects like 2001 PM9 sometimes prompts some urgent
emails to the small band of follow up stations out here taking pictures and
making measurments. Our group here in Kansas at Powell Observatory is just
one of those stations. When we saw the email traffic on 2001 PM9 from NEODys
and others, we prioritized our observations of 2001 PM9. We have a larger
than normal aperture amateur telescope and a brand new back illuminated
super sensative CCD camera funded by a grant from NASA's Office of Space
Science. What would be an object too fast moving and faint with our old
camera was now an easy target and Kyle Smalley was able to get more than one
night of data on 2001 PM9, contributing to the improved orbital
determination.

Would this have been done without the emails from NEODys and private emails
from others?  Maybe not. So it did some good, didn't it? You can sleep
easier tonight, because it was done. Doesn't that make it worthwhile? So a
little ink was used and some bandwidth consumed. Maybe it will motivate some
folks to take these matters more seriously and speed up the funding of the
research and help fill in that huge blind spot in the southern hemisphere.

We few here in Kansas, all volunteers, and in particular, Kyle Smalley, who
spends every clear night at Powell Observatory, enjoy the opportunity to
contribute what we can, when we can.  We leave it to Brian Marsden and
others to sort out the political implications of the urgent announcements
and how to handle information dissemination to the public. Just so long as
we know how we can help soon enough to do some good is all we few really
care about. Let's not let the flap over matters like 2001 PM9 cause the
communications to slow down or shut down, just because someone might be
embarrassed in the press. There is really nothing to be embarrassed about.

Cheers...

Larry Robinson
Sunflower Observatory 739
14680 W 144th Street
Olathe KS 66062
lrobinsn@ix.netcom.com

===============
(12) 2001 PM9 & INTERNATIONAL SPACE COOPERATION REPORT

>From Andy Smith <astrosafe@yahoo.com>

Hi Benny and CCNet,

We think you are handling the 2001 PM9 situation appropriately. Scare or
alarm articles will be
written, from time to time, as the World becomes increasingly aware of the
danger we face. We strongly encourage a rapid response from the "truth team"
(as you did, in this case) and we urge the IAU to speed-up the processing
time for new discoveries...so the truth can get out quickly.

PHA Definition Needs Attention

The present cut-off size for potentially hazardous asteroids (PHA) is Mag.
22. It is our impression that objects smaller than that are not included on
the PHA lists (NEODys, MPC). Such an object would be about 400 meters wide
and be equal, in destructive energy, to about 1,200 million tons (megatons)
of TNT.

We think objects that size and smaller (down to the Tunguska  or Barringer
size - 50 meters wide and Mag 25 or so) should be included on the PHA lists.
They are extremely hazardous and should be tracked and given the same
attention as the larger rock-bombs. We think the MPC and NEO/DYS teams are
doing great jobs and we hope they and their IAU colleagues will make this
adjustment.

International Space Cooperation Report

It was good to hear from the UN Office of Outer Space Affairs (CCNet,
yesterday) and we hope many of you will look at the Workshop Report which
was mentioned. This appears to have been a very productive meeting.

We were surprised to see no mention, in the report, of the two landmark and
very supportive AIAA position statements, made in 1991 and 1995. The first
statement, as you know, led to the very important series of international
conferences that were held in the U.S., Russia, Italy and elsewhere, in the
early 1990's. Also the two U.S. Congressional hearings held on planetary
defense were not mentioned and neither the Spaceguard nor the Space Shield
Foundations were recognized. Spaceguard has major organizations, now, in
several countries and Space Shield is providing major global leadership, in
the study of issues related to mitigation.

In addition, there was no mention of the fact that the entire decade of the
1990's was designated, by the U.N., as the Decade for Natural Disaster
Reduction and meetings and conferences were held, during that period, all
over the World and those activities are still continuing (see Web
citations). The activities were sponsored by the United Nations and repeated
attempts were made, by many of us, to get the asteroid/comet danger included
on the list of natural threats and those attempts were ignored, at both
national and international levels.

Much of the difficulty we face, as we try to focus attention on the
important matter of asteroid/comet (AC) protection, is concerned with the
need to inform leaders, and to get them to support key programs......and we
should not underestimate that need. The funding requirment, for example, to
complete the vital NEO data base (100,000 objects or so)in a decade, rather
than 300 years, is relatively small...if we can get an appropriate priority
assigned. The total cost of the program would be less than half the cost of
one shuttle flight....and the results could very well save humanity.

Finally, we want to call to the attention of those now trying to organize
the long overdue international program, that there is a newly formed Natural
Hazards Caucus in the U.S.Senate and it does not recognize the AC danger. We
invite them and all of the CCNet and AIAA devotees to contact and inform
them. This program is also easy to find on the Web.

There are at least 2,000 specialists, around the World, who are spending a
lot of volunteer time on this important matter and we hope the planners of
the future Workshops will keep us informed of meeting plans and available
information products. This excellent newsletter (CCNet) would be a great
information channel. It would also be helpful to hold the next meeting in
the U.S. and to give support to the many ongoing and very important
programs, here.

We appreciate, very much, the availability of the March Workshop report, on
the Web, and the results of the Workshop were impressive. We hope the work
will continue and we urge full openness and high visibility, in the future.

Cheers
Andy Smith

===============
(13) PLANETARY DEFENSE

>From Christian Gritzner <christian.gritzner@mailbox.tu-dresden.de>

Dear Benny,

just a brief comment on the note "DOUBTS ABOUT PLANETARY DEFENSE" by John
Michael Williams in CCNet 92/2001 - 23 August 2001:

Because nuclear explosives for NEO mitigation will be operated in the vacuum
of space the energy is transfered only by radiation. Beside the thermal
radiation there will be a high portion of x-rays and emmitted neutrons
(depending on the type of the nuclear explosive) which will
interact with the surface of the asteroid or comet. It is assumed that the
radiation will heat up the surface layer and spall it away producing an
impulse on the remaining NEO. This effect may be intensified when performing
a surface or sub-surface explosion. The major concern with nuclear
explosives is an undesired fracturing or partial/total destruction of the
NEO.

For further information have a look at the report of the "Planetary Defense
Workshop", 1995:
http://www.llnl.gov/planetary/

The book "Hazards due to comets and asteroids" by Tom Gehrels (editor), The
University of Arizona Press, 1994, ISBN 0-8165-1505-0, gives a good
overview, too!

With kind regards,
Christian Gritzner
--
Dresden University of Technology
Institute for Aerospace Engineering
Dr.-Ing. Christian Gritzner, Senior Engineer
01062 Dresden, Germany
Tel.: +49-(0)351-463-8234 (Fax: -8126)
E-mail: christian.gritzner@mailbox.tu-dresden.de
Homepage: www.tu-dresden.de/mw/ilr/space/space.htm

============
(14) "RED HOT KILLER ASTEROID"

>From Phil Plait <badastro@badastronomy.com>

Hi Benny--

In the CCNet  92/2001 - 23 August 2001 there was this letter:

>A nuclear bomb operates mainly by release of immense amounts of heat. The
>only way it creates mechanical stress at any significant distance is because
>of changes in air pressure caused by the
>heating. Everyone reading this must be familiar with the mushroom-shaped
>cloud, which represents the leftover heated air, that which did not
>contribute to the shock wave in nearby air. A nuclear bomb probably would do
>little more to an approaching "killer asteroid" than to make it red hot, too
>hot to touch.

Ah, but that's the point! As planetologist John Lewis comments in his
fascinating book "Rain of Iron and Ice", detonating a nuclear weapon a few
asteroid radii off the surface heats it substantially. This vapor then
expands rapidly, exerting a push on the asteroid itself. In this way, the
orbit of the asteroid can be modified. Given a long enough lead time (as is
always the case when trying to toss around objects of this kind of mass) the
orbit can be turned from malignant to benign.

The exact execution of this sort of orbital manipulation depends on many
factors, not the least of which is the composition of the asteroid itself.
This to me is one of the best reasons to send more probes to NEAs.

-Phil

*    *    *    *    *    The Bad Astronomer    *    *    *    *

Phil Plait                    badastro@badastronomy.com
The Bad Astronomy Web Page: http://www.badastronomy.com

===========
(15) DEFLECTION OF ASTEROIDS WITH NUCLEAR BOMBS

>From Michael Paine <mpaine@tpgi.com.au>

Dear Benny

Re John Michael Williams comments about nuclear deflection.

I covered the topic of deflecting asteroids in a series of articles for
Space.com last year. Links and references are at:
http://www4.tpg.com.au/users/tps-seti/reading.html#ez8

Very briefly, a "stand-off" nuclear blast is favored because it is less
likely to shatter a fragile asteroid (leading to the more deadly shotgun
effect when it reaches Earth). Much of the energy from the stand-off blast
is wasted but the theory is that enough radiant energy reaches the surface
of the asteroid to vaporise material which then flies off into space. This
gives the asteroid a small impulse in the opposite direction (away from the
blast). The important point about the Spaceguard effort is that the earlier
an Earth-threatening asteroid is detected the smaller the nudge that is
needed to prevent a collision. Ideally such deflections should take
place dozens of orbits before impact (say 100 years, with typical orbits
around 3 years) and a nudge is applied during successive orbits until the
asteroid is declared safe.

I also reviewed non-nuclear methods of deflection. Some could be quite
feasible within a few years, although the size of the nudge would probably
be less than with nuclear bombs.

I actually started researching this issue a few years ago when, to my
annoyance, an Australian politician stated on TV that there was no point in
looking for asteroids because there was nothing we could do if one was found
to be on a collision course!

regards
Michael Paine

===========
(16) DEFLECTION OF ASTEROIDS WITH NUCLEAR BOMBS

>From John Michael Williams <jwill@AstraGate.net>

Hello Benny and Michael.

I think EARLY identification of approaching objects, and rapid evaluation of
their mechanical characteristics, would have to precede effective defense efforts.

For example, a modified ICBM with 10-ish megaton warhead might be able to
bury itself deep enough  in a comet to blow it up, with a favorable result
much the same as a detonation in air or water. 

However, launching of one or more nuclear missiles from Earth into the
distance would be extremely risky, and the damage done by a failed launch
might be worse than that of a small asteroid impact.

Thus, I think a Moon base would be a better idea than Earth-launched efforts
or the flying of huge chemical depots near the upper-atmosphere orbital
station (ISS). Materials could be transported in a safe and leisurely way to
the Moon, there to be dispatched on
riskier missions. This my favorite reason for advocating establishment of a
Moon base.  However, although I favor nuclear power on the Moon, I think in general heavy
weaponry should be avoided, even weaponry intended for humanitarian
purposes.

The issue of deflection of stony or solid, (effectively) cast-iron asteroids
is quite a different one from that of comets. Given enough warning, a big rocket motor
might be brought in contact, aligned with the asteroid's center of gravity,
and thus the asteroid's course might be changed. 

Although I haven't done the calculations, I am sure the energy usage and
momentum transfer would be better by burning 1 kton of hydrogen in a rocket, than by
detonating a 1 Mton thermonuclear bomb to get an ounce of photons and a few hundred kg of
gasified metal. As has been rumored, in fact, E = m*c^2--and c is a VERY big number.

I would like to point out that one big asteroid would be far more deadly
than the same broken into small pieces. The pieces would be subject to greater atmospheric
ablation and reduction of velocity, in view of the greater surface-to-volume ratio. Also, larger
impactors would be associated with lower-frequency, longer-wavelength
effects, which would spread damage farther than the same mass in smaller
pieces.

There is no way, unfortunately, to get a nuclear
missile in position for enough reaction force to
pulverize a solid asteroid in vacuum.   A drilling
operation would have to be mounted.

That said, I did read a couple of the postings at Michael's link. His
opinions seem more or less to follow Solem's at that site,
http://www.llnl.gov/planetary/.  

I disagree with the opinion that nuclear explosives would be of use against
a solid asteroid, unless time did not permit a more effective response.
Solem's statement that a nuclear bomb could "blast a crater" in the side of
a solid rock in vacuum seems unlikely to be correct. No air; no blast.
However, I am not sure of the benefit of spending the time to do the
calculations to prove this.

I should only like to point out that the insight of the participants at the
site above seemed mostly based on wartime and cold war testing in air,
against targets in surface soil or water, and usually made of inflammable
material. A cubic kilometer of cast iron would be a beast of another genre.

Quite honestly, I think the fear of an asteroid impact is an idle one. As
Dr. Laura Schlessinger once asked, "What is the difference between a
chronically fearful woman and a drug addict?"

The correct answer: "Nothing".

So, maybe a preventive dose of "Vitamin Moon" might do no harm; but, arming
ISS to blow up asteroids would be more of a shot in the head than one in the arm.

--
                         John
                     jwill@AstraGate.net
                     John Michael Williams

==========
(17) UPDATE ON TUNGUSKA

>From Luigi Foschini <foschini@tesre.bo.cnr.it>

Dear Friends and Colleagues,

the Italian Scientific Expedition Tunguska99 has been carried out on July
1999, just 2 years ago. Now, first results begins to appear. You can find
new publications (abstracts and preprints) at the Tunguska web page of the
University of Bologna: http://www-th.bo.infn.it/tunguska/
specifically at the page dedicated to publications.

Among new publications, it is worth noting that the full paper (17 pages):

P. Farinella, L. Foschini, Ch. Froeschlé, R. Gonczi, T.J. Jopek, G. Longo,
P. Michel:
Probable asteroidal origin of the Tunguska Cosmic Body.

has been accepted for the publication by Astronomy and Astrophysics. This
work originated from an idea of the late Paolo Farinella, deceased on March
25th, 2000. We dedicate it to him.

A preprint (PS or PDF) is available at the web page written above.

Greetings,

Luigi Foschini

 Dr. Luigi Foschini
 Istituto TeSRE - CNR
 Via Gobetti 101, I-40129 Bologna (Italy)
 Tel. +39 051.6398706 - Fax +39 051.6398724
 Email: foschini@tesre.bo.cnr.it
 Home : luifosc@tin.it
 URL: http://tonno.tesre.bo.cnr.it/~foschini/

===========
(18) SCIENCE AND APPLICATIONS OF THE SPACE ENVIRONMENT

>From Duncan Steel <D.I.Steel@salford.ac.uk>

Forwarded from ROBIN CLEGG <ROBIN.CLEGG@PPARC.AC.UK>

Colleagues at MSSL have asked me to advertise to the list a 3-day seminar
with this title.  It's at the Royal Society London, from 16-18 October.

The space environment is a multi-discpilinary topic in science, applications
and engineering.  There are ntaural connections in terms of scientific
techniques and the space technologies required.

The meeting's main goals are:  to identify links between different science &
technology areas;  identify gaps in science, interpretation and
applications; and to indentify underlying technologies.

Main topics are: Observation of the Earth (including climate change, land
and ocean monitoring);  Sun-Earth Connection; Hazard Warning (including
storms, space dust and debris);  and Space and Spacecraft Technologies
(including communications, cryogenics, software and miniaturization).

A press conference will be held in conjunction with the start of the
meeting.

Further details from www.mssl.ucl.ac.uk/www_seminar/roy.html  or from
Rosalind Medland, Mullard Space Science Laboratory (rer@mssl.ucl.ac.uk)

Robin Clegg

_________________________________
Dr Robin Clegg
Head, Public Understanding of Science & Technology
Particle Physics and Astronomy Research Council
Polaris House, North Star Avenue,
Swindon, SN2 1SZ, UK
Tel +44 (0)1793 442010
Fax +44 (0)1793 442002
Email Robin.Clegg@pparc.ac.uk

=============
(19) TAGISCH-LAKE METEORITE & SIR FRED HOYLE

>From Hermann Burchard <burchar@mail.math.okstate.edu>

Dear Benny,

the leading German paper DIE WELT is reporting on the Tagish Lake Meteorite
in great detail, emphasizing its uniquely primitive composition, wealth of
organic molecules including Fullerenes, agreement of chemistry with the
spectra of type D asteroids from the outer belt, and grains
"older than the solar system."

http://www.welt.de/daten/2001/08/24/0824astr277065.htx

Sir Fred Hoyle must have been delighted by the fortuitous recovery when it
occurred, as this confirmed some of his predictions (not sure about reports
of comments by him). I did see that he was quoted as believing in a universe
without limits in time and space, and denying the Big Bang, so named by him.
The less well known Inflationary Universe (in which we inhabit a small
fractal bubble if I got it right) would seem to suit his criteria better. I
wonder if a cosmology along those lines should not allow models without
beginning and end.

Mathematically the exact meaning of such statements is unclear, as even
things like the infinite line, plane, space, etc, are among many entities in
a mathematical, logical world, each with numberless copies.  Such a world is
unlimited in other ways - often in paradoxical manner - explored by Georg
Cantor and Kurt G"odel. It is interesting to note that G"odel has published
on cosmology.

Immanuel Kant would have had none of any of this as being "outside of the
bounds of any possible experience", and I think he was largely right. What
eluded even him was the clear methodical distinction between our logical,
linguistic accounts of the universe, among which all of mathematics,
theoretical physics, and all cosmologies must be reckoned on the one hand,
and the actual universe on the other. The true question is then why this
universe does allow us to form logical, linguistic accounts of itself (which
are of course an albeit minuscule part of it).

Sir Fred's work - even if not always universally accepted - was honored on
CCNet by those who know him best whom I wish to join with admiration for a
vigorous proponent of the unity of science.

Regards,

Hermann G.W. Burchard

-------------------------------------------------------------------
THE CAMBRIDGE-CONFERENCE NETWORK (CCNet)
--------------------------------------------------------------------
The CCNet is a scholarly electronic network. To subscribe/unsubscribe,
please contact the moderator Benny J Peiser <b.j.peiser@livjm.ac.uk>.
Information circulated on this network is for scholarly and educational use
only. The attached information may not be copied or reproduced for
any other purposes without prior permission of the copyright holders. The
fully indexed archive of the CCNet, from February 1997 on, can be found at
http://abob.libs.uga.edu/bobk/cccmenu.html
DISCLAIMER: The opinions, beliefs and viewpoints expressed in the articles
and texts and in other CCNet contributions do not  necessarily reflect the
opinions, beliefs and viewpoints of the moderator of this network.

CCCMENU CCC for 2001