PLEASE NOTE:


*

CCNet, 74/2000 -  10 July 2000
-------------------------------


     "Project Icarus was only a study proposal. [...] There have been
     several unofficial asteroid defense proposals made by various
     aerospace experts in the ensuing 33 years, including some
     utilizing the now-defunct Soviet Energia booster. None of them
     were as carefully planned as the Icarus project. Today the issue
     of asteroid defense still has a high "giggle factor" associated
     with it — nobody in power in the American government takes the
     threat seriously.”
         -- Dwayne A. Day


     "The fact is that everyone is free to use the Torino Scale
     according to their own interpretation. Attempts to stifle
     scientific criticism of its flaws or to gag its critics are not
     only unjustified but simply have no place in the world of
     scientific debate and research."
         -- Benny J. Peiser


(1) VERY BIG BOMBS & ROCKETS: ARMAGEDDON FOR REAL
    Larry Klaes <lklaes@bbn.com>

(2) BAD NEWS FOR PLANETARY DEFENSE: MISSILE TEST FAILS TO
    INTERCEPT WARHEAD. LUCKILY, JUST A ROCKET, NOT AN ASTEROID!
    YAHOO! News, 9 July 2000

(3) SOME COMETS LIKE IT HOT
    NASA Science News <science.news@msfc.nasa.gov>

(4) SPACE PROTECTION OF THE EARTH 2000
    Ron Baalke <baalke@jpl.nasa.gov>

(5) NEAR-EARTH ASTEROID SAMPLE RETURN WORKSHOP
    Ron Baalke <baalke@jpl.nasa.gov>

(6) IMPACTS & EXTINCTIONS
    Michael Paine <mpaine@tpgi.com.au>

(7) TORINO SCALE - A REASSESSMENT
    Jonathan Tate <fr77@dial.pipex.com>

(8) ATTEMPTS TO SILENCE TORINO SCALE CRITICS ARE FUTILE
    Benny J Peiser <b.j.peiser@livjm.ac.uk>

=============
(1) VERY BIG BOMBS & ROCKETS: ARMAGEDDON FOR REAL

From Larry Klaes <lklaes@bbn.com>

From Florida Today, 4 July 2000
http://www.flatoday.com/space/explore/special/icarus.htm

Very big bombs and rockets: Armageddon for real

By Dwayne A. Day

A SPACE ONLINE special report

VIENNA, Va. - In recent years, Hollywood has thrilled audiences with
asteroid movies. In the absurd 1998 hit Armageddon, oil driller Bruce
Willis led a valiant effort to stop a killer chunk of planetary matter from
sending humanity the way of the dinosaurs.

But over thirty years ago, a group of engineers-in-training at the
Massachusetts Institute of Technology designed a far more realistic
defense against a doomsday rock. Their plan would have involved a half
dozen Saturn 5 rockets carrying some really big bombs.

Every nineteen years the large asteroid Icarus swings by planet Earth,
often coming within four million miles of the planet - mere spitting
distance in astronomical terms. Icarus last passed by Earth in 1997.
Before that, its previous approach was in June 1968.

In early 1967, MIT professor Paul Sandorff gave his class of graduate
students a task: suppose that instead of passing harmlessly by, Icarus
was instead going to hit the Earth. The nearly mile-wide chunk of rock
would hit the planet with the force of 500,000 megatons - far larger
than any major earthquake or volcanic eruption. Over 33,000 times the
size of the bomb that destroyed Hiroshima. At a minimum, it would kill
millions, flattening buildings and trees for a radius of hundreds of
miles, and/or causing huge tidal waves that would wipe out coastal
cities along thousands of miles of coastline. It could even lead to a
global winter that could last years. Sandorff posed a simple challenge:
"You have fifteen months. How do you stop Icarus?"

MIT was then deeply involved in the Apollo program. The guidance system
for the Apollo spacecraft was developed there and the country’s
foremost experts in aviation and space walked the school’s halls.
Sandorff’s proposal was intended to teach his students how to improvise
under pressure. Intense pressure.

The class immediately split up into several working groups based upon
their areas of expertise: orbits and trajectories, boosters and
propulsion, spacecraft, guidance and control, communications, economics
and management, and nuclear payloads. They began evaluating the
different options for defeating the killer rock.

Could they launch a big bomb to the asteroid and blow it to pieces?
Quick calculations showed that pulverizing a rock the size of Icarus
would require a 1,000 megaton bomb. No nuclear weapon even remotely
that big had ever been theorized, let alone designed or built. There
was no way it could be done in the short time available. Using a bunch
of smaller bombs was also not possible because they would all have to
be detonated at exactly the same time. Otherwise, one bomb would
vaporize the others before they detonated.

The most desirable option would be to rendezvous with Icarus when it
reached aphelion - the slowest point in its orbit - in November 1967.
At that point it would be easiest to rendezvous with the slow-moving
asteroid and easiest to exert force to change its orbit. But such a
mission would have had to be launched immediately, in spring 1967, and
so it was out of the question. The group quickly determined that no
rockets could conceivably be readied before 1968 and this greatly
constrained their options. A slow rendezvous, or even a soft landing,
was therefore totally out of the question: Icarus would be moving too
fast by 1968 for a spacecraft to reach it and then reverse direction
for a rendezvous.

Fast Intercept

The only option was a fast intercept - fly out to Icarus and detonate a
bomb near the surface to change its course.

The best way to get the most payload to Icarus was to launch two
modified Saturn 5 rockets into orbit. These would rendezvous with an
Apollo 'space tug' launched atop a Titan 3 rocket. The space tug would
connect up the modified S-4B third stages from the Saturns. They would
then be used to push a relatively large spacecraft out to Icarus where
it would detonate a large nuclear weapon.

But there were many problems with this proposal. The Saturn S-4B third
stages were not designed to carry fuel in orbit for more than six hours
and would require extensive modification. A spacecraft would also have
to be designed from scratch and built in under a year. Most
importantly, the on-orbit operations required to link up the large
craft were extensive and unproven. There would be no way to practice.
This plan was rejected.

What the group decided to do was to take six Saturn 5 rockets then in
production, and with only minimal modifications to their payloads, use
them to carry smaller bombs to Icarus. The first launch would have to
take place by April 1968, only a year away, and five more launches
would have to follow at two-week increments.

The actual Icarus spacecraft would have consisted of an Apollo Service
Module (SM) with a five-foot cylindrical extension known as the Payload
Module (PM) at the top. Instead of a Command Module, the top of the
stack would be a simple aluminum cone containing a few necessary
systems. Although the Apollo Command Module and its associated guidance
and control systems would have been useful, its weight was prohibitive
and unnecessary. Weight had to be kept to a minimum in order to enable
the rocket to carry the biggest possible bomb.

The Bomb

The Payload Module would have carried a 100 megaton bomb shaped as a
cylinder roughly three feet in diameter and mounted horizontally along
the diameter of the spacecraft. The bomb would weigh 40,000 pounds. One
side of the PM would sport a phased array radar antenna for tracking
and rendezvous with the Icarus asteroid.

The plan would have used an essentially unmodified Saturn 5 rocket. At
the time, the first Saturn 5 test was not scheduled until November 1967
and the planners did not know if it would work. The only real
difference with the Icarus Saturn 5 was the modified adapter shroud at
the top of the S-4B third stage. On a standard Apollo mission to the
moon these panels normally would have enclosed the Lunar Module, with
the Service Module and Command Module mounted on top. But, by modifying
them and using them to enclose the Service Module and its attached
Payload Module, the designers were able to improve the aerodynamics of
the rocket, and more importantly, eliminate aerodynamic loads and
heating on the radar antenna. In profile, the stack would have looked
much like the Skylab launch vehicle lofted by the Saturn 5 in 1974,
although with minor differences.

The 100 megaton bomb would have been a challenge. At the time, the
largest weapon ever developed for the American nuclear arsenal was a
25 megaton bomb. The Soviets had detonated a 58 megaton bomb earlier in
the decade which could have easily been developed into a 100 megaton
weapon. However, although the Soviets have not (and still have not)
released the weight of this bomb - they were never as good at
miniaturizing their bombs as the United States. It is likely that their
100 megaton bomb would have weighed far more than the 40,000 pound
weight limit for Icarus. The United States would have had to build its
own bomb to save the planet.

The Rockets

The Icarus plan required a total of nine Saturn 5 rockets. Three were
test flights and the remaining six were interceptors. At the time, NASA
planned on having only six Saturn V’s available by April 1968, so the
production schedule would have to be dramatically increased. In
addition, another launch pad would have to be built at Cape Kennedy.
Launch Complex 39-C would have to be built, north of the two existing
pads, in order to enable the high flight rate needed for the Saturn
launches, all of which had to get off the ground in six weeks.

In addition to the nine Saturn 5s, the Icarus plan called for five
Atlas Agena rockets carrying modified versions of the Mariner II deep
space probe. Known as the Intercept Monitoring Satellite (IMS), these
probes would be used to observe the actual detonation of the nuclear
bombs when they reached the asteroid. Very little was known about how
nuclear weapons would actually behave in space, let alone how the blast
would affect an asteroid, and so the IMS was considered vital to the
mission.

Interceptor One

In late February 1968, the first IMS spacecraft would lift off atop its
Atlas Agena booster. It would linger in Earth orbit only a short time
before being sent on its way to rendezvous with Icarus. A little over a
month later, Interceptor One would thunder aloft on seven and a half
million pounds of thrust. After a coast of one orbit or less, the S-4B
stage would fire, boosting the Icarus spacecraft out of earth orbit and
toward the asteroid. Soon after, the adapter shroud panels would peel
back like the petals of a flower and the Icarus spacecraft with its 100
megaton bomb would separate. Its Service Propulsion System engine would
fire, adding more velocity to the spacecraft.

After a coast of approximately 60 days, with several course corrections
along the way, an optical sensor aboard the spacecraft would acquire
Icarus only three hours before rendezvous. The spacecraft then entered
the 'terminal phase.' Four minutes before rendezvous the radar system
would begin to supply range information for making final correction
maneuvers. At five seconds before impact, a fuzing radar would acquire
the asteroid and arm the bomb. If all went as planned, detonation would
occur within 100 feet of the surface of Icarus along the sunlit edge.
The resulting explosion would either fragment or deflect the killer
rock off its collision course.

The IMS spacecraft would monitor the detonation with its sensors,
relaying the data back to earth so that the mission planners could
refine their calculations. At the time that Interceptor One would reach
Icarus, Interceptor Two would be right behind it by only a couple of
weeks. And several more would be following right on Interceptor Two’s
heels. Most of these would be accompanied by an IMS flight. But there
was only time enough to launch five IMS flights.

The planners proposed six bombs for the mission. But they faced huge
unknowns. The biggest problem was that nobody knew exactly what
asteroids in general, and Icarus in particular, were made of. Was
Icarus dense or light? Exactly how big was it? How was it shaped?

Furthermore, nobody was sure how a nuclear bomb would act in space or
how it would affect Icarus. There was no way to get everything right on
the first try and so several bombs would have to be detonated before
planners even began to understand what they were doing. And if one or
more of the bombs was a dud, or detonated too far from the asteroid,
the mission controllers would have to improvise quickly as their thin
stream of Interceptor spacecraft streaked heavenward to save the
planet.

All this time, Icarus would be heading toward earth.

Conclusion

Project Icarus was only a study proposal. It was never formally adopted
or even evaluated by the United States government. There was no
independent evaluation of whether or not the proposal was even
feasible. There might be some hidden flaw to the plan that was never
identified. The MIT group did brief a number of people in the NASA on
the proposal, however, and several of the MIT grads later went to work
for the space agency.

There have been several unofficial asteroid defense proposals made by
various aerospace experts in the ensuing 33 years, including some
utilizing the now-defunct Soviet Energia booster. None of them were as
carefully planned as the Icarus project. Today the issue of asteroid
defense still has a high “giggle factor” associated with it — nobody in
power in the American government takes the threat seriously.

But the Project Icarus model is probably worth dusting off and trying
again either as an exercise for aerospace engineering students or for a
government science and engineering advisory board. Although it would
not be a valid contingency plan, at least it would help to identify our
options in the event that something like this happened. If humanity
suddenly realized that an asteroid was heading our way and we had only
two years to respond, could we do something? Or would we simply be
condemned to sit back and stare at the clock, waiting for the brief
flash in the upper atmosphere signifying impending doom?

Dwayne A. Day is an independent space policy analyst living in Vienna,
Virginia. He holds a Ph.D. from The George Washington University and
has written numerous articles on civilian and military space policy and
history. He was the primary editor for "Eye in the Sky: The Story of the
CORONA Spy Satellites". He is a frequent contributor to SPACE
ONLINE.

================
(2) BAD NEWS FOR PLANETARY DEFENSE: MISSILE TEST FAILS TO
INTERCEPT WARHEAD. LUCKILY, JUST A ROCKET, NOT AN ASTEROID!

From YAHOO! News, 9 July 2000
http://dailynews.yahoo.com/h/nm/20000709/ts/arms_usa_missiles_dc_2.html

U.S. Ponders Next Move on Missile Defense

By Charles Aldinger

WASHINGTON (Reuters) - A U.S. attempt to intercept and destroy a target
warhead in space failed on Saturday, leaving the Pentagon wondering
what went wrong and the White House wondering whether to proceed with
the controversial National Missile Defense (NMD) system.

"We did not intercept the warhead tonight. We are disappointed," Air
Force Lt. Gen. Ronald Kadish, director of the missile defense effort,
told reporters early on Saturday after the weapon failed a $100 million
test to separate from its booster rocket and intercept the dummy
warhead over the Pacific Ocean.

FULL STORY at
http://dailynews.yahoo.com/h/nm/20000709/ts/arms_usa_missiles_dc_2.html

See also: National Missile Defense - DoD Post-Test News Briefing
http://www.spacedaily.com/news/bmdo-00zzg.html

===============
(3) SOME COMETS LIKE IT HOT

From NASA Science News <science.news@msfc.nasa.gov>

NASA Science News for July 07, 2000

Amateur astronomers are discovering pieces of a giant comet that broke
apart in antiquity as the fragments zoom perilously close to the Sun.

July 7, 2000 -- In October 1965 comet Ikeya-Seki swooped past the Sun
barely 450 thousand kilometers above our star's bubbling, fiery
surface. Gas and dust exploded away from the comet's core as fierce
solar radiation vaporized the icy nucleus. Most comets wouldn't survive
passing as close to the Sun as the Moon is to the Earth, but Ikeya-Seki
literally came through with flying colors. When the comet emerged
from perihelion (closest approach to the Sun) it was so bright that
observers on the street with very clear skies could see it during broad
daylight if the Sun was hidden behind a house or even an outstretched
hand.

"In Japan (where observers spied the comet 1/2 degree from the Sun)
it was described as 10 times brighter than the Full Moon," recounted
Brian Marsden of the Harvard Center for Astrophysics in the December
1965 issue of Sky & Telescope. "At Kitt Peak National Observatory in
Arizona, Stephen Maran observed the comet with binoculars from within
the shadow of a black disk erected to hide the Sun. '[It was] the most
splendid thing I have ever seen,' he noted."

Ikeya-Seki, a.k.a. "The Great Comet of 1965", is a member of the family
of comets called Kreutz sungrazers (after the nineteenth-century German
astronomer who studied them in some detail). These ill-fated visitors
to the inner solar system have been seen to pass less than 50,000 km
above the Sun's photosphere. Most never make it past perihelion -- they
are completely obliterated. But the few that do, like Ikeya-Seki, can
be very bright.

"There are 2 or 3 really bright ones like Ikeya-Seki every century,"
says Brian Marsden. "Most of these sungrazers are fragments from the
breakup of a giant comet at least 2000 years ago, perhaps the one that
the Greek astronomer Ephorus saw in 372 BC. Ephorus reported that the
comet split in two. This can be made to fit with my calculation that
Ikeya-Seki and an even better Kreutz sungrazer observed in 1882 split
off from each other when their parent revisited the Sun around AD 1100.
Splits have occurred again and again, producing the sungrazer family,
all still coming from the same direction."

The nucleus of Ikeya-Seki was probably some kilometers across. Tinier
pieces of Ephorus's comet streak past the Sun every day. Measuring
perhaps only ten meters in diameter, they brighten briefly as they
approach the Sun and disappear forever when they vaporize above the
photosphere. Most of the faint fragments must have escaped detection
entirely.

Now, thanks to coronagraphs on board the orbiting ESA/NASA Solar and
Heliospheric Observatory (SOHO), amateur and professional astronomers
can easily monitor the sky around the Sun for the telltale streaks of
faint sungrazers. All that's needed is a computer and a connection to
the internet.

"In late1998 we put SOHO's realtime coronagraph movies online so that
anyone with an internet connection could access the data" says Doug
Biesecker, a solar physicist at the Goddard Space Flight Center and
SOHO's champion comet hunter with 47 finds. "Over a three year period
before that time we had found 58 comets near the Sun in SOHO images.
Now the total is up to nearly 170. Amateur astronomers watching
coronagraph movies on the web are responsible for nearly all of the new
finds this year. They're keeping me very busy!"

A coronagraph is a device that blocks the glare of the Sun so that the
faint corona, as well as surrounding stars and planets, are visible.
It's a sophisticated version of the black disk Stephen Maran used to
see Ikeya-Seki in 1965. The SOHO spacecraft carries two coronagraphs,
one with a 3-degree field of view (the "C2" coronagraph) and another
with a 16-degree field of view (the "C3" coronagraph). SOHO is located
at the L1 point 1.5 million kilometers from the Earth in the direction
of the Sun. It enjoys an uninterrupted view of our star.

One of the most successful amateur comet hunters is Michael Boschat.
He's credited (or shares credit) with a dozen discoveries since March
2000.

"I use the C3 512 x 512 pixel images," explains Boschat. "They appear
on the SOHO site every 30 minutes and I download them as soon as they
do. After I have four images I begin to loop them using GIF animation
software that can be found on the Internet. I usually loop them at four
frames per second looking for an object that is moving towards the Sun
in a steady manner. I also use a magnifying glass to watch the possible
comet move. After I feel it is a comet I put my mouse arrow as near as
possible to the object to get the X and Y coordinates then send all that
information off via email to Douglas Biesecker at Goddard."

All of the comets identified in images from SOHO are called "comet
SOHO" followed by a number denoting the order of discovery. This
differs from the traditional convention of naming a comet after the
person who finds it. The most recent confirmed sungrazer, as of July 4,
2000, was comet SOHO-143. The International Astronomical Union's
official designation for SOHO-143 is C/1998 K15, because the actual
images were obtained in 1998, with the K15 indicating that this was the
fifteenth comet (of any description) found during the second half of
May.

"It started in the early 1980s with the SOLWIND mission, which also
carried a coronagraph," explains Biesecker. "SOLWIND detected 6
sungrazers and they were all named after the satellite. The tradition
continued for the Solar Maximum Mission (10 comets) and now for SOHO
(143 confirmed comets and counting). It's reasonable because all of the
comet finds have to be confirmed by mission scientists who are familiar
with the hardware. Cosmic rays, noise in the detectors and other
factors can mimic comets and we have to carefully examine each one. It's
really a team effort."

"In the early 1980s there were also the 'IRAS' comets, found by the
Infrared Astronomical Satellite," added Marsden. "Most of the comets
found nowadays from the ground--and far from the sun--are named
'LINEAR', acronym for the Lincoln Near Earth Asteroid Research team,
which scans the sky intensely with a U.S. Air Force telescope." (One of
these is about to become a naked eye object in late July, 2000.)

Biesecker says he hopes the recent spate of amateur discoveries will
continue unabated. 

"The amateur discoveries are important because they can help us
understand the fragmentation history of Kreutz sungrazers by monitoring
the numbers and brightness of the smallest ones that we can see with
the SOHO coronagraphs. The amateurs are also finding a few unrelated
'near-Sun' comets [this is not an official name] that pass within 10 to
20 solar radii of the Sun. This is an under-sampled population of
comets."

If you're interested in joining the hunt for sungrazing comets, a good
place to start is the Solar and Heliospheric Observatory's realtime
images web page where coronagraph data are posted every 30 minutes,
and sometimes even more frequently. Data from the satellite are
available to the general public at the same time as to the scientific
community. If you think you've found something, first review the basic
criteria for a discovery before forwarding the details to scientists at
the Goddard Space Flight Center. Confirmed finds are posted daily on
the "What's New" area of http://sungrazer.nascom.nasa.gov.

SOHO (the Solar and Heliospheric Observatory) is a mission of
international cooperation between NASA and the European Space Agency.
It is managed by the Goddard Space Flight Center for the NASA HQ office
of Space Science.

=========================
(4) SPACE PROTECTION OF THE EARTH 2000

From Ron Baalke <baalke@jpl.nasa.gov>

http://www.snezhinsk.ru/spe2000/
http://www.snezhinsk.ru/asteroids/
http://www.snezhinsk.ru/asteroids/eng/spe2000/
Space Protection of the Earth - 2000
Third International Conference
September 11-15, 2000, Evpatoriya, Crimea, Ukraine

First Announcement
 
Conference Dates and Location

Series of international conferences "Asteroid Hazard"
(Saint-Petersburg) and "Space  Protection of the Earth" (Snezhinsk,
former Chelyabinsk-70) were held in Russia in 90s. They were devoted to
one of the most complicated problems facing by the mankind - protection
of the Earth from the threat of its collision with asteroids and
comets. Distinguished scientists and specialists from many countries of
the world including Russia, the U.S. and other contributed to the
conferences.

The vital urgency of the problem is emphased by scientific information,
which has been accumulated about the role of the space collisions in
the history of the Earth and mankind, and predictions of destruction
effects. The interest to this problem has been growing year by year
since new scientific data and technologies appear that could be used to
prevent such catastrophe.

The next third Conference "Space Protection of the Earth - 2000"
(SPE-2000) will take place in Crimea in Evpatoriya city on September
11-15, 2000. Crimea is not only a well-known Black Sea health resort
but a place where astronomical (optical and radiolocation) observations
of asteroids and comets are fulfilled as well as control of the
interplanetary space satellites studying the solar system objects.

The Conference is organized by the Russian Federal Nuclear Center
(All-Russian Scientific Research Institute of the Technical Physics)
(RFNC-VNIITF), Lavochkin Association (LA) and the Institute of
Technical Mechanics (ITM) of the National Academy of Sciences of
Ukraine and Ukrainian Space Agency, Scientific Technical Foundation
"Space Shield" supported by Minatom RF, Russian Aerospace Agency,
Ukrainian Space Agency and some other organizations.  

Conference Goals

The objectives of the conference are to assess the state of scientific
researches in the sphere of planetary protection from asteroids and
comets; to workout recommendations for their further development; to
wide contacts among specialists and to attract people's
attention to this problem. In addition, it is planned to consider some
associated problems, for example, feasibility assessment of utilizing
small celestial bodies in the interests of mankind and space science
development.

Areas of Interest

1. Asteroid and comet hazard

Asteroid and comet encounters with the Earth and other celestial bodies
(real events and their consequences, classification, modeling, risk
assessment);

Existing technology of detection and observation of small celestial
bodies (ground methods and means, space missions);

Results of studying asteroids and comets (characteristics, orbit,
engineering, physics and other models);

2. Scientific and technological aspects of creating the defense devices
against hazardous celestial bodies

Conceptual basis for ensuring Earth defense as well as protection of
other objects (problems, requirements, principles and design schemes,
application scenarios, etc.);

Technologies for detection, support and research of the near-Earth
objects (NEOs) (methods, means, design and interaction schemes,
potentialities of amateur astronomy, etc.);

Technologies of delivery means of influence to dangerous celestial
bodies (rocket-space systems, ballistics, navigation, approaching and
pointing dynamics, etc.);

Technologies of acting onto dangerous celestial bodies (methods,
safety, kinetic means, nuclear, etc.);

Information support and control (information acquisition and
processing, decision making, warning, control of the components and
their interaction);

Work-out of the planetary defense system components (space missions,
demonstration experiments, schemes, means, sensors, etc.);
Miscellaneous (integration, safety, economics, etc..);

3. Social aspects of planetary defense

Ecological, political, legislation and other problems;

International co-operation;

4. Prospects and problems of utilizing asteroid and comet resources

Articles aimed to resolve some specific problems of Planetary defence
system development will be of higher priority.

Co-chairman of the program committee

Vadim A. SIMONENKO - Deputy Scientific Director of RFNC-VNIITF
Konstantin G. SUKHANOV - Deputy Chief Designer of Lavochkin Association

FOR CONFERENCE DETAILS see:
http://www.snezhinsk.ru/asteroids/eng/spe2000/
http://www.snezhinsk.ru/asteroids/
=============
(5) NEAR-EARTH ASTEROID SAMPLE RETURN WORKSHOP

From Ron Baalke <baalke@jpl.nasa.gov>

http://cass.jsc.nasa.gov/meetings/asteroid2000/                        

                  Near-Earth Asteroid Sample Return Workshop
                             December 11-13, 2000
                        Lunar and Planetary Institute
                                Houston, Texas

                            First Announcement

                                  SPONSORS

                           University of Arkansas
                        Lunar and Planetary Institute
                National Aeronautics and Space Administration


                             STEERING COMMITTEE

                 Derek Sears, Chair, University of Arkansas
                     Dan Britt, University of Tennessee
                   Don Brownlee, University of Washington
                   Andrew Cheng, Johns Hopkins University
                 Benton Clark, Lockheed Martin Astronautics
                  Leon Geffert, NASA Glenn Research Center
                      Steve Goreven, Honeybee Robotics
                Marilyn Lindstrom, NASA Johnson Space Center
                       Carle Pieters, Brown University
                       Jeff Preble, SpaceWorks, Inc.

                            CONTACT INFORMATION

                             Scientific Program:
                                Derek Sears
                      Workshop Program Committee Chair
                            dsears@comp.uark.edu

                        Announcements and Logistics:
                              LeBecca Simmons
                          LPI Workshop Coordinator
                            simmons@lpi.usra.edu

     It is widely recognized that comet, asteroid, and meteorite
     research is at a point in its history where sample return from a
     known geologic context is essential, and several past workshops
     have stressed the need for such missions. Near-Earth asteroids
     (NEAs) are also important as potential Earth impactors, targets
     for human exploration and development of space (HEDS), and
     resources for space stations and colonies. Several developments in
     the last year or so mean that it is now technically feasible to
     fly NEA sample return missions. The NEAR Shoemaker mission
     demonstrated the feasibility of orbiting and performing complex
     maneuvers near small asteroids. The Deep Space 1 mission validated
     solar electric propulsion and automatic navigation. Most
     important, the explosion in the rate at which NEAs are being
     discovered means that targets of diverse spectral classification,
     including some that might be extinct comets, come within range of
     a multiple NEA sample return mission. The Japanese MUSES-C
     mission, which will return samples from asteroid ML 1989, is
     scheduled for launch in 2002.

     The meteorite, comet, and asteroid research communities all
     recognize the need for sample return from asteroids. Asteroids
     provide a unique opportunity to investigate primitive solar system
     materials, including presolar materials and potentially biogenic
     materials, and processes that occurred in the early solar system
     and subsequently. Both asteroid and comet nucleus sample return
     have been advocated in the NASA Space Science Strategic Plan and
     Roadmaps. A previous workshop was held at Milipitas, California,
     in 1989.

     The purpose of this workshop is to bring together people of highly
     diverse backgrounds so they can identify the scientific issues
     best addressed by NEA sample return. Discussion could include
     recommendations on mission design that would ensure the highest
     scientific return. The workshop will also explore the role of
     asteroid sample return in HEDS, impact mitigation, and resource
     utilization.

     The Near-Earth Asteroid Sample Return Workshop will have four
     goals: (1) to identify the major scientific issues that can be
     uniquely addressed by NEA sample return; (2) to identify the
     requirements and constraints this places on the design of such
     missions; (3) to explore the extent to which such requirements and
     constraints can be met by existing technologies and identify any
     necessary technology developments; and (4) to consider the role of
     NEA sample return missions in HEDS, Earth impact mitigation, and
     resource utilization.

     These goals will be addressed in four theme sessions: Session 1,
     "The Scientific Case for Sample Return," will discuss the progress
     in asteroid, comet, and meteorite research possible through the
     analysis of NEA samples. Session 2, "Spacecraft Maneuvers in the
     Vicinity of Small asteroids," will concern the navigation and
     control requirements of sampling from the surface of small
     asteroids. Session 3, "Sample Collection Devices, Sample
     Containment, and Planetary Protection Issues," will deal with
     options for collecting samples and storing them for return to
     Earth. Discussion may address issues of sampling procedures
     without contaminating the asteroid, without contaminating the
     samples during sampling, and returning the samples to Earth
     without cross contamination. Session 4, "Implications for
     Near-Earth Asteroid Sample Return for Resource Utilization, Impact
     Hazard Mitigation, and Human Exploration and Development of
     Space," will discuss possible wider implications of sample return
     to life on Earth and our exploration of space. Each session will
     consist of invited reviews, contributed talks, and poster
     presentations. Summary sessions will be the basis for a short
     report and recommendations.

     Contributions to Session 1 ("The Scientific Case for Sample
     Return") are solicited from asteroid, comet, and meteorite
     specialists interested in the compositional and physical
     properties of small planetary bodies and their histories. Of
     special interest are contributions discussing the asteroids and
     comets as potential meteorite parent bodies, and the important
     scientific issues best addressed by sample return.

     Contributions to Session 2 ("Spacecraft Maneuvers in the Vicinity
     of Small Asteroids") are solicited from experts in orbital
     dynamics and spacecraft control and navigation. Orbiting small
     irregular-shaped asteroids presents novel challenges, but many
     advances have been made in recent years.

     Contributions to Session 3 ("Sample Collection Devices, Sample
     Containment, and Planetary Protection Issues") are invited from
     industrial and academic specialists with expertise in developing
     methods for collecting representative samples and storing them for
     return to Earth. Contributions are also invited from engineers and
     exobiologists who are experts in planetary protection, sample
     cross contamination, and contamination of the samples during
     collection and storage.

     Contributions to Session 4 ("Implications for Near-Earth Asteroid
     Sample Return for Resource Utilization, Impact Hazard Mitigation,
     and Human Exploration and Development of Space") are invited from
     the community interested in HEDS, Earth impactors, and NEAs as a
     natural resources. Emphasis should be on the role of sample return
     missions in furthering the objectives of these areas of research.

     FURTHER INFORMATION

     Further details regarding abstract submission, the program, and
     logistics will be included in the second and final announcements.
     Indication of interest forms are due to LPI by July 30, 2000. You
     MUST return either the downloadable Indication of Interest form
     (PDF format) or complete the electronic Indication of Interest
     form in order to receive future announcements.

     ------------------------------------------------------------------
                                  SCHEDULE

             July 30, 2000     Indication of Interest forms due
                               at LPI

             August 11, 2000   Second announcement mailed

             September 25,     HARD-COPY abstract submission
             2000              deadline

             October 2, 2000   ELECTRONIC abstract submission
                               deadline

             November 1, 2000  Final announcement mailed

             November 10,
             2000              Preregistration deadline

             December 11-13    Near-Earth Asteroid Sample
             2000              Return Workshop

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

(6) IMPACTS & EXTINCTIONS

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

Dear Benny,

Duncan Steel's comments about confusion over the consequences of
impacts (CCNet, 29 June 2000) are very relevant to my (stalled)
investigations of the Indo-China impact 800,000 years ago. The signs
are that the impactor was between 2 and 5km in diameter and therefore
would have caused global climate disruption and severe conditions for
Homo Erectus. There seems, however, to be no evidence of major
extinctions at the time - and Homo Erectus survived the event of
course. I am sure however, that such an impact today would cause global
crop failures and starvation and, likely, a collapse of civilisation
(it would take far less to cause a collapse of the fragile global
economy). There would also be severe effects from the complete loss of
the ozone layer for months or possibly years. I have summarized my
findings and the possible effects of large impacts at
http://www1.tpgi.com.au/users/tps-seti/climate.htm

The point is that these impacts take place on timescales of hundreds of
thousands of years - not the tens of millions of years associated with
'extinction level events'.

regards
Michael Paine

================
(7) TORINO SCALE - A REASSESSMENT

From Jonathan Tate < fr77@dial.pipex.com >

Benny,

The piece below is for the CCNet, if you deem it appropriate.  It is
already doing the rounds between the members of the Board of Directors
of the SGF, and is bound to cause a bit of a stir - though not too much
I hope.

Jay


The Torino Scale Alternative - A Reassessment.
or "The Perfect is the Enemy of the Good"

By J.R. Tate
Spaceguard UK

Since its introduction more than a year ago at the Torino IMPACT
symposium, the fortunes of the Torino Scale have followed something of
a twin track. Thanks to a blizzard of NASA publicity the Torino Scale
is well on the way to becoming the standard reference for popular
publications and the media for assessing the impact hazard. In the
meantime, within the professional community the scale has become the
centre of significant controversy and discussion. There has been a
substantial amount of "the Torino Scale is useless* / inaccurate* /
misleading*" (*delete where inapplicable) chat, but surprisingly no
realistic alternatives have been produced. This can only be because of
one of two reasons:

a. There isn't one.

b. The professional community doesn't care about explaining its
   findings to the public.

I assume that the former is the case.

For reasons that we need not dwell upon (mea culpa - in part), the
Torino Scale has been little used outside the United States, despite
the fact that there have been at least two suitable occasions since its
inception. Discussions with the media have inevitably involved more
detailed descriptions than provided by the Scale, but have tended to be
inconsistent and consequently confusing.

There is no doubt that the Torino Scale can be revised or improved.
However, there has been only one serious suggestion to date, despite
the number of individuals criticising the scale. Some of you may have
seen, and possibly even have read the alternative to the Torino Scale
that I have been working on. My proposal was, in effect, a modified
Torino Scale, with the addition of the time to impact factor. It is now
clear that the Torino Scale is to be used with such a rider.

There is obviously no ideal translation of this multidimensional
problem into a simple one (or two) dimensional system. However, in the
current debate we have reached a clear point of diminishing return when
the public perception is that we (the NEO community) is divided and
cannot make up its mind. We could continually tweak and change any
system, but all that would achieve would be frustration and confusion
from the public, politicians and the media. We are already faced by a
very unsatisfactory public image ("Astronomers change their minds -
again - and say asteroid won't hit the Earth after all") and constantly
changing our communication system - at least in the near term - will
only make the situation worse.

There is no doubt in my mind that it is in the best interest of the NEO
community and of the society that we purport to serve, that we
communicate information about potential threats in a common and clear
language. Many of us have been vocal in our objections to the Torino
Scale, but no one has come up with a better solution. So, imperfect as
it is, we should us it with confidence and without complaint.  Anything
else would be at best a disservice to public and at worst,
irresponsible in the extreme.

The Torino Scale has been well publicised, and provides the basis for
the NEO community to demonstrate a sense of unity with simple, clear,
and efficient communications to the media, public and emergency
services. Given the Torino Scale's professional publication and
world-wide media exposure I believe that we should now accept the
"Torino Scale" as it stands, on the understanding that significant
changes and/or improvements will be thoroughly discussed and agreed in
the appropriate forum prior to publication.  This stipulation is in no
way intended to stifle proposals or to "protect" the Torino Scale, but
is solely to avoid confusion, turmoil and apparent incompetence within
the NEO community. We should all do our best to explain and use the
scale to our "customers" - the public and media.

I therefore strongly urge the NEO community as a whole to accept the
Torino Scale, on the understanding that the time to a predicted 
encounter must be added. This will provide our customers with a
consistent and easy to interpret indication of the current impact
probability, the consequences should such an event occur and the time
available for mitigative action.

After a year without any better solutions we are out of time.  Before
you jump all over me for changing my mind on this, please consider the
following questions:

a. Have you got a better suggestion?

b. Can you convince the world's press that yours is a better idea?

If the answer to either question is "no", the time has come for the NEO
community to do something almost unique and agree on a matter of
crucial importance. We can either do so now, or continue to bicker
without agreement for years to come, thereby remaining a divided and
unconvincing group, lacking the public's confidence.

Jay Tate
Spaceguard UK

=========================
(8) ATTEMPTS TO SILENCE TORINO SCALE CRITICS ARE FUTILE

From Benny J Peiser < b.j.peiser@livjm.ac.uk >

Jay Tate is concerned about the public image of the NEO community. He
believes that the public has no confidence in this scientific group or
its announcements as long as it lacks complete agreement - particularly
regarding the controversial "Torino Scale." Commenting on the two last
asteroid scares, Jay reprimands researchers who provided the media with
"more detailed descriptions than provided by the Scale" dangerous
information which he considered "to be inconsistent and consequently
confusing."

This is not the right place to discuss the blunders made in the public
announcements regarding PHAs 2000 BF19 and 2000 EW70. I do think,
however, that Jay is somewhat naive to expect that researchers should
only refer the media and science journalists to the Torino Scale -
refusing any additional comments furthermore.

The Torino Scale may have been intended as a tool for the scientific
community to "demonstrate a sense of unity with simple, clear, and
efficient communications." The truth remains, however, that is has
never gained unambiguous support. In fact, an increasing number of
researchers have lamented the flaws inherent in the Torino Scale and
have called for significant changes and revisions. To demand from these
critics, as Jay does, that they should now "use it with confidence and
without complaint" is a futile exercise. But to accuse researchers and
colleagues who do not wish to use the Scale as being "irresponsible in
the extreme" is, I regret to say, wholly inappropriate and over the
top.

In contrast to party politics, scientific debate and research interact
in a system of openess, pluralism and disagreement. This is the very
essence of scientific progress and development. There is no reason why
the Torino Scale should be treated like a dogma or party manifesto.
After all, its recent publication has brought it into the public domain
for general assessment. Only the future will tell whether or not it
might be more widely used and accepted as it currently is.

The fact is that everyone is free to use the Torino Scale according to
their own interpretation. Attempts to stifle scientific criticism of
its flaws or to gag its critics are not only unjustified but simply
have no place in the world of scientific debate and research.

Benny J Peiser


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