PLEASE NOTE:


*

CCNet 23/2001 - 8 February 2001
-------------------------------


"For a long time now, Earthlings have been threatening to move
heaven and Earth in order to get this or that accomplished. Politicians
promise to do so before every election. Moms seem to manage, at least
metaphorically, to do it every day. Now a group of scientists says it
could be done for real."
--Robert Roy Britt, Space.com, 7 February 2001


"There is, of course, no need to move our planets position in the
solar system. [...]
Perhaps the most interesting implication of this suggestion is what
it means for the human race as a whole. The Russian astronomer Nikolai
Kardashev suggested that civilisations could be classified into four groups
of which ours is a type 0 civilisation, struggling for survival on a single
planet that we can't control. The knowledge and the ability to modify the
configuration of a planetary system to create a more hospitable and
efficient environment is one of the criteria for a type II
civilisation. Shifting planets around in a game of cosmic billiards
being an ingenious alternative to the construction of a Dyson sphere. We
now have the knowledge and the ability, all we lack is the impetus. In short
it appears the human race has just been promoted."
--Matthew Genge, The Natural History Museum, 7 February 2001


(1) UA SCIENCE TEAM READIES FOR NEAR LANDING
    Ron Baalke <baalke@jpl.nasa.gov>

(2) RECIPE FOR SAVING EARTH: MOVE IT
    Space.com, 7 February 2001

(3) DEBRIS COLLISION ADVOIDANCE PREDICTIONS
    Andrew Yee <ayee@nova.astro.utoronto.ca>

(4) SPECTAL FEATURES USED TO DETERMINE ORBITAL DEBRIS
    Andrew Yee <ayee@nova.astro.utoronto.ca>

(5) REMINDER: RAS MEETING TOMORROW ON THE GEOLOGICAL RECORD OF IMPACTS ON
THE EARTH
    Jacqueline Mitton <aco01@dial.pipex.com>

(6) PERMO-TRIASSIC
    Doug Erwin <Erwin.Doug@NMNH.SI.EDU>

(7) COSMIC BILLIARDS AND THE PROMOTION OF THE HUMAN RACE
    Matthew Genge <M.Genge@nhm.ac.uk>

(8) A BETTER UNDERSTANDING OF DR. SIMONENKO'S POSITION
    Worth Crouch <doagain@jps.net>

(9) PLANETARY DEFENSE
    Andy Smith <astrosafe@yahoo.com>

============
(1) UA SCIENCE TEAM READIES FOR NEAR LANDING

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

http://uanews.opi.arizona.edu/cgi-bin/WebObjects/UANews.woa/wa/SRStoryDetails?ArticleID=3134

UA SCIENCE TEAM READIES FOR NEAR LANDING
(From Agnieszka Przychodzen, UA Lunar and Planetary Lab)

CONTACT: William V. Boynton,  520-621-6941, wboynton@lpl.arizona.edu
(EDITORS - Boynton is available for interviews at the UA through Friday,
Feb. 9)

NASA's Near Earth Asteroid Rendezvous (NEAR) mission, the first to orbit an
asteroid, is coming to an end.

February 7, 2001

With the spacecraft almost out of fuel, on Feb. 12 mission engineers will
attempt the first-ever, controlled descent to the surface of an asteroid.
NEAR has been orbiting asteroid 433 Eros since Feb. 14, 2000 and is now more
than 196 million miles (316 million kilometers) from Earth

The main goal of the controlled descent is to gather close-up pictures of
the surface of Eros, particularly the saddle area, a six-mile (10-km) wide
depression peppered with huge boulders and cut with grooves.

"The landing will take a few hours. We'll see the images coming in real time
as the NEAR spacecraft is approaching closer and closer to the asteroid's
surface," William V. Boynton said.  Boynton, professor of planetary sciences
in the UA Lunar and Planetary Laboratory, leads the UA group involved in the
NEAR mission.

Boyton and the UA team will watch the descent at the Applied Physics
Laboratory (APL) in Laurel, Md., which built the spacecraft and managed the
mission.

NEAR Shoemaker's 4-hour descent is scheduled to start at 10:31 a.m. EST. A
series of thruster firings will decelerate the spacecraft from about 20 mph
to 5 mph.

"It is not really a landing in the sense of a spacecraft being alive once it
touches down. NEAR has no legs to steady it, so it's just going to fall
over. The antenna will no longer point to the Earth so we'll not be able to
communicate with it," Boynton said.

NEAR's camera will be taking a photo every minute. The last clear images,
shot from about 1,650 feet (500 meters), could details on the surface as
small as 4 inches (10 centimeters) across.

"If the instruments survive the touch down we will not be able to see
whatever the camera will be looking at. NEAR will snap the last image just
before it reaches the surface," Boynton added.

During its one-year orbiting mission, the NEAR Shoemaker spacecraft provided
among other data X-ray, gamma ray, and infrared readings on the composition
and spectral properties of the asteroid. Initial results from the X-ray
Gamma Ray Spectrometer suggested that Eros might be similar in elemental
composition to primitive meteorites called chondrites.

"Previously Eros was thought to be a very standard meteorite, but now it
looks that it might be like a meteorite we've never seen before.  Its
composition might be different than that of typical meteorites. There might
be some very rare meteorites that resemble Eros, but right now we're not
sure. We need to wait for another few months for complete analyses results
to find out, says Boynton, who is the principal investigator for NEAR's
X-ray  Gamma Ray Spectrometer.

"One thing that has been learned from this mission is how to operate the
spacecraft up close with an irregularly shaped body that has very little
gravity. Because of its strange shape, the gravity on Eros is not constant
like it is with a spherical body, such as Earth or Mars.  When one of the
asteroid's lobes comes by, the pull of gravity is greater. It is very
complicated to take all of these effects into account," Boynton explained.

Though the mission has been successful, there are still some mysteries to be
solved.

"One interesting thing we still don't understand is why there are some
places which have a lot of very large boulders. They are unexpected. We
don't see them on the moon. The saddle area is the region where we see
grooves looking like cracks around Eros, and we are not sure what caused
them," he said.

Eros almost certainly used to be a piece of a now extinct, bigger object. At
one time in the past, Eros got knocked off due to a large impact. The shock
from that event might have left the cracks.

"We don't know when it happened. The space where Eros resides is crowded
enough to have such collisions today. In order to answer this question we
would have to land on it, pick up a sample, and bring it back to Earth for
analysis." Boynton said.

What would he recommend for future asteroid missions?

"If we had the opportunity to do this again, I'd want to land on the surface
with instruments designed to measure the surface composition and bring the
samples back," Boynton said.

The UA NEAR team has began archiving the spectra data collected by
NEAR-Shoemaker and will make them available to other scientists for
analysis. The task will take about 12 months.

=============
(2) RECIPE FOR SAVING EARTH: MOVE IT

From Space.com, 7 February 2001
http://www.space.com/scienceastronomy/planetearth/earth_move_010207.html

By Robert Roy Britt
Senior Science Writer

Give me a place to stand, and I will move the Earth.
-- Archimedes, circa 235 BC


For a long time now, Earthlings have been threatening to move heaven and
Earth in order to get this or that accomplished. Politicians promise to do
so before every election. Moms seem to manage, at least metaphorically, to
do it every day. Now a group of scientists says it could be done for real.

Well, heaven might have to stay put. But with existing technology, some
advance planning and a little orbital energy, courtesy of a redirected
asteroid, Earth's distance from the Sun could be increased by 50 percent in
just a few billion years.

It's a scheme that could save the planet, at least for a while. Because if
Earth stays in its current orbit, we are doomed.

Hot death

Just as sure as the Sun comes up every morning, it is scheduled to die.
Experts give it some 7 billion years, when it will turn into a bloated red
giant. As the name implies, a red giant is a star swelled to gargantuan
proportions. Earth would be first engulfed in heat and light, then
vaporized.

Well before then, things will turn real nasty. In just a billion years, the
Sun could be 11-percent brighter, scientists say, rendering Earth an
inhospitable greenhouse. In 3.5 billion years, the Sun could be 40-percent
brighter than it is today.

With our demise so clear on the cosmic horizon, astrophysicist Fred Adams of
the University of Michigan and NASA's Gregory Laughlin got to wondering in
recent years how the planet might be saved by gravitational interaction with
a passing star. They ran computer simulations of possible encounters over
the next 3.5 billion years, finding last year that the odds of the Earth
being completely ejected from the solar system are one-in-100,000.

Slim odds. And life in the frigidity of deep space would be no summer
picnic.

So Adams and Laughlin, along with Don Korycansky of the University of
California, Santa Cruz, began to discuss consider how human intervention
might bring about a more suitable long-term orbit, one that gradually
expands with the aging Sun.

Their idea, which evolved from interaction with a star to rerouting a giant
space rock to save Earth, will be published in an upcoming issue of the
journal Astrophysics and Space Science.

Just an idea

"This is not an urgent problem," Adams stressed, adding that the researchers
merely wanted to prove -- on paper -- that such a scheme was possible. "And
we are in no way advocating policy."

Call it mathematical recreation.

After working for years and to determine the fate of the entire universe --
with results published in the 1999 book, The Five Ages of the Universe:
Inside the Physics of Eternity -- the researchers spent two weeks modeling
our escape because, Adams said, scientists and reporters kept asking, "What
happens to Earth? Is there a way out?"

They started with a simulated comet or asteroid 62 miles (100 kilometers)
wide, about six times larger than the one thought to have killed off the
dinosaurs 65 million years ago. The solar system has plenty of objects like
this -- in the main Asteroid Belt between Mars and Jupiter, and farther out
in the Kuiper Belt. The trick is to find one that's headed our way, then use
a small amount of energy to guide it, like a spacecraft, onto a new course
through our solar system.

FULL STORY at
http://www.space.com/scienceastronomy/planetearth/earth_move_010207.html

=========
(3) DEBRIS COLLISION ADVOIDANCE PREDICTIONS

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

[From January 2001 issue of ORBITAL DEBRIS QUARTERLY NEWS, NASA JSC
http://www.orbitaldebris.jsc.nasa.gov/newsletter/v6i1/v6i1-3.html]

Flight Readiness Review Report
By M. Matney

Before every Shuttle mission, the Orbital Debris Program Office performs a
Flight Readiness Review (FRR) for the mission. Primarily, this consists of a
detailed analysis of the Shuttle sensitive surfaces with the Bumper code to
determine the debris and meteoroid risk to the vehicle and mission. Each
mission has a target risk level that can be altered by the flight geometry
during the mission. This risk calculation is based on the standard debris
and meteoroid models and does not take into account short time-scale
variations in the collision risk. For this reason several analyses are
performed to estimate any enhancement to the baseline risk for a particular
mission.

The first source of possible enhancement is that an annual meteoroid shower
could peak during the mission that might temporarily increase the net
meteoroid flux over the short two-week Shuttle mission. Currently, we use a
model of shower activity based on ground observations to compute a simple
meteoroid flux enhancement factor to be added to the Bumper results. Because
meteor showers typically last only a few days, it may be possible to shift
the launch time of a mission to avoid the strongest outbursts of meteoroid
activity such as a Leonid meteor storm.

The second source of possible enhancement is that the Shuttle might fly
through a dense region of debris from a recent on-orbit breakup event. This
could potentially add an enhanced flux onto the time-averaged ORDEM flux
used by Bumper. The SBRAM code is used each Shuttle mission to compare all
recent breakups to the future Shuttle orbit to look for potential debris
cloud enhancements.

During each Shuttle mission, US Space Command performs collision avoidance
predictions for all catalogued objects in Earth orbit. The purpose is to
give the Shuttle a warning in case an object is predicted to enter a
collision warning "box". Currently, this "shoe box" is 10 km long in
down-track direction, and 4 km wide in radial and cross-track directions.
NASA is assessing a new "pizza box" that is 14 km wide in down-range and
cross-track directions, and 2 km wide in the radial direction. Future
collision avoidance calculations should include more sophisticated estimates
of the actual estimated position uncertainties computed by Space Command.

The FRRs are performed some weeks before the actual mission -- too early to
compute actual collision probabilities. However, the flight directors like a
"heads-up" on the expected number of collision warnings they may expect for
the mission. For typical Shuttle missions, this number is less than one, so
that the prediction becomes the probability that a collision warning will be
issued during this mission. This probability is computed using the latest
catalog at the time of the FRR using simple estimates of the collision flux
based on average flux models. We are working on improving our ability to
make these estimates by using more orbit plane prediction information.

We are always improving the FRR process, and are also assessing how we can
provide similar information on a regular basis to the International Space
Station program in the future.

===========
(4) SPECTAL FEATURES USED TO DETERMINE ORBITAL DEBRIS

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

[From January 2001 issue of ORBITAL DEBRIS QUARTERLY NEWS, NASA JSC
http://www.orbitaldebris.jsc.nasa.gov/newsletter/v6i1/v6i1-3.html]

Spectral Features Used to Determine Material Type of Orbital Debris
By K. Jorgensen

An ongoing investigation continues on determining the material type of
small-to medium-sized debris using reflectance spectra features. Knowledge
of the physical properties of orbital debris is necessary for modeling the
debris environment. Current methods determine the size and mass of orbital
debris based on knowledge or assumption of the material type of the piece.
By using spectroscopy, one can determine the material type of the piece by comparing
the absorption features of its spectra to that of lab spectra for given
materials. By isolating three wavelength regions, material types can be
placed into three main categories: aluminum, other metals, and plastics.
Using these three categories, one can make better-educated assumptions of
the material type. The goal of this research is not to improve the models
themselves, but to improve the information others use to make the models.

A database of common spacecraft material spectra has been collected and
contains currently over 300 types of materials. This database will be used
as a comparison library once observations of orbital debris have been taken.
The material type will be determined based on comparisons to the library.

As an example of the absorption features seen on spacecraft materials,
Figure 1
[ http://www.orbitaldebris.jsc.nasa.gov/newsletter/v6i1/jorgensenfig1.jpg ]
displays three spacecraft materials, aluminum 1100, carbon epoxy, and steel,
over the same wavelength region. The three wavelength regions used to
determine material type are 0.5-1.0 Ám, 1.5-1.9 Ám, and 2.1-2.3 Ám. In the
first region, aluminum shows a strong absorption feature near 0.8 Ám, which
makes the material easy to pick out when comparing spectra. Steel, as well
as other metals, tends to show a general increase in slope as wavelength
increases. Plastics and epoxies of organic nature show absorption features
due to C-H and/or O-H in the final two regions in the infrared. Seen in
Figure 1 are absorption features in the carbon material due to C-H near 1.6
Ám and between 2.1 and 2.3 Ám.

In order to determine the effects of the space environment on the
reflectance spectra of spacecraft materials, researchers measured materials
from returned spacecraft. Measurements of material degradation for returned
missions such as the Long Duration Exposure Facility (LDEF), the Passive
Optical Sample Assembly I and II (POSA I and II), and the Evaluation of
Oxygen Interaction with Materials (EOIM-3) were conducted. The measurements
gave insight to the effect of thermal coatings and paints on the reflectance
spectra of various materials.

Figure 2 shows a plastic, Polyetheretherketone (PEEK), flown as part of
experiment number A0171 in experiment tray A8 on LDEF.
[ http://www.orbitaldebris.jsc.nasa.gov/newsletter/v6i1/jorgensenfig2.jpg ]

This sample was obtained from Marshall Space Flight Center (MSFC);
accompanying the sample was a control piece of PEEK. When compared to the
control sample the flown sample shows a decrease in the total reflectance as
seen in Figure 2. A slight discoloration is seen on the exposed sample near
0.55 Ám and was noted visually while testing the sample. A comparison of the
strengths of the absorption feature in near 1.7 Ám shows the C-H band
decreasing in the flight sample. The feature is still apparent and still
strong enough to detect through on-orbit observations, but is definitely not
as strong as it was prior to flight. The C-H features in near 2.1 and 2.35
Ám are both the same strength in the control and flight samples. When the
regions deemed necessary for determining the material type of orbital debris
through on-orbit spectral measurements are examined, it appears that the
space environment does not change significantly the absorption features seen
in plastics in those regions.

When the spectra of returned spacecraft materials were compared with the
pre-flight laboratory spectra degradation in the samples were seen mostly in
the visible wavelengths, while the samples showed similar features in the
near-infrared. Overall, the results displayed less degradation on the
spaceflight samples than anticipated. The strengths of absorption features
were relatively the same in pre- and post-flight measurements. The three
wavelength regions chosen, 0.5 - 1 Ám, 1.5 - 1.8 Ám, and 2.1 - 2.35 Ám were
proven to be viable regions in their ability to determine the material type
of the spacecraft sample using the absorption features.

The next step in this study is to begin examining of the reflectance spectra
of debris still in orbit. Along with on-orbit observations, a continual
building of the spacecraft material database is very important. As different
paints, plastics, and metals are put onto spacecraft, pre-flight and
post-flight measurements should be taken. A more detailed study of the
various coatings would be ideal as well. Currently, the majority of coatings
placed on the metals have been tested, but the plastics and paints should be
tested also. Since physical characteristic data on the small- and
medium-sized debris is relatively unknown, any information obtained on the
material type and thus albedo would help researchers improve models and
shields. Continued correlation of radar observations and optical
observations coupled with spectral observations would greatly improve the
knowledge base of physical characteristics of the debris environment.

============
(5) REMINDER: RAS MEETING TOMORROW ON THE GEOLOGICAL RECORD OF IMPACTS ON
THE EARTH

From Jacqueline Mitton <aco01@dial.pipex.com>

ROYAL ASTRONOMICAL SOCIETY
PRESS INFORMATION NOTE

Date: 5 February 2001

Ref. PN 02/04
Issued by: Dr Jacqueline Mitton
RAS Press Officer
Office & home phone: Cambridge ((0)1223) 564914
FAX: Cambridge ((0)1223) 572892
E-mail: jmitton@dial.pipex.com

(On the day of the meeting, please use Jacqueline Mitton's mobile phone
number, 07770 386133.)

RAS Web: http://www.ras.org.uk

THE GEOLOGICAL RECORD OF IMPACTS ON THE EARTH AT ROYAL ASTRONOMICAL
SOCIETY'S LONDON MEETING ON FEBRUARY 9TH

This one-day discussion meeting in the Royal Astronomical Society's regular
monthly programme will review and challenge current understanding of
cratering and impacts throughout the history of the Earth, setting a context
for possible disaster scenarios in the future, which might involve comets,
meteorites,  or asteroids. There will be contributions on some of the best
direct geological evidence for impacts, discussions of global threats,
frequency of impacts, known and potential extinction events, and the
devastating secondary consequences of impacts, which may include
earthquakes, tsunamis, landslides, and volcano activity. The keynote talk is
by Christian Koeberl (Vienna), President of the IMPACT programme  of the
European Science Foundation (web site http://ww.esf.org/).

Media representatives are welcome to attend. The meeting is in the
Geological Society Lecture Theatre at Burlington House, Piccadilly, London,
W1.

Meeting organisers: Dr Adrian Jones, University College London
(adrian.jones@ucl.ac.uk), Professor David Price, University College London
(d.price@ucl.ac.uk), and
Dr Monica Grady, Natural History Museum (mmg@nhm.ac.uk).

An outline of the programme is given below.

For more information, contact Dr Adrian Jones
Department of Geological Sciences, University College London, Gower Street,
London WC1E 6BT
Tel:    0207 679 2415/2408
Fax:    0207 388 7614
email:  adrian.jones@ucl.ac.uk


Programme:

10.25-10.30       Introduction by Chairman, Professor G. David Price,
University College London

10.30-11.00       1     Evidence of the late heavy bombardment
                        Christian Koeberl (Institute of Geochemistry/Vienna)

11.00-11.20       2     The Chicxulub impact structure: a review
                        Mike Warner (Imperial College London)

11.20-11.40       3     ChicxulubII: Nature of the K/T projectile?
                        Matthew Genge (Natural History Museum, London)

11.40-12.00       4     Large impacts and impact volcanism?
                        Adrian Jones (University College London)

12.00-12.20       5     Timing between flood basalts and impacts.
                        Simon Kelly (Open University, Milton Keynes)

12.20-12.40       6     Holocene Impacts and the Difficulties of Detection
                        Benny Peiser (Liverpool John Moores University)

12.40-12.55       7     Simulation of terrestrial shock metamorphism
                        Emma Bowden (University College London)

Afternoon session: (Chair Monica Grady)

14.00-14.15       5     The flux of extraterrestrial material to the Earth'
                        Phil Bland (Open University, Milton Keynes)

14.15-14.30       6     NEO-uniformitarianism: are impacts random in time?
                        Duncan Steel (University of Salford)

14.30-15.00       7     Regularities in impact records; possible cometary causes
                        Bill Napier (Armagh Observatory, Northern Ireland)

15.00-15.15       8     Origin of the K/T Impactor: Comet or Asteroid?
                        Mark Bailey (Armagh Observatory, Northern Ireland)

15.15-15.30       9     Microtektites: exoatmospheric distribution of impact ejecta.
                        Ralph Lorenz (Lunar Planetary Lab, Arizona)

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

(6) PERMO-TRIASSIC

From Doug Erwin <Erwin.Doug@NMNH.SI.EDU>

Dear Dr. Peiser,

Relative to Dr. Simonenko's message today, I should remind participants that
although there is fairly credible evidence of impact associated with the KT
boundary, there is as yet NO credible evidence of impact associated with the
Permo-Triassic mass extinction.  The paleontologic, geochronologic and
carbon isotopic data from South China is CONSISTENT with an impact, but is
also consistent with other scenarios.  The Woodleigh structure in western
Australia is not well dated, and in a recent comment and reply in Earth and
Planetary Science Letters Mory et al. revealed the structure may be as old
as Late Devonian - Early Carboniferous.  Curiously, a paper will be
appearing in several weeks with evidence that might suggest a PT impact, and
it will be interesting to see how the impact community evaluates this paper.

Best,
Doug Erwin

===========
(7) COSMIC BILLIARDS AND THE PROMOTION OF THE HUMAN RACE

From Matthew Genge <M.Genge@nhm.ac.uk>

Don Korycansky, Gregory Laughlin and Fred Adams have suggested that the
Earth's orbit could be changed in order to moderate the Earth's climate. The
technique is relatively simple and, rather worryingly, perfectly possible
using modern day technology. Just change the orbit of a large
asteroid so that it comes close enough to the Earth to change our planet's
angular momentum. This technique is nothing new, in fact it was responsible
for the migration of the planets four and a half billion years ago whilst
they cleared the solar system of left over planetesimals. Korycansky,
Laughlin and Adams rather sensibly acknowledge that this would be a delicate
operation since aiming a huge rock at the Earth does have one or two minor
risks associated with it. The extinction of 75% of species on the planet
being one of them. Rather a heafty price to pay for clement weather.

Using long term propulsion techniques such as mass drivers or solar sails
the change in the orbit of an asteroid could be achieved very reliably and,
secular perturbations allowing, the idea would work. There would be some
small things to check first. Changing the Earth's orbit would change its
perturbation of the orbits of the other planets, asteroids and comets and
you would certainly not want to move directly into the path of an impactor.
It is perhaps this 'safety first' task that is beyond our current knowledge.

There is, of course, no need to move our planets position in the solar
system. It would be folly indeed to try and compensate for a short term
climatic disturbance such as global warming even if we could reliably
predict how our planet's climate would change after the move. Only in 4.5
billion years or so when our Sun starts to become a red giant will the
inhabitants of the Earth perhaps have to think about taking such drastic
action. It would, in any case, be politically rather difficult for any
government to unilaterally decide to move the global vegetable patch to a
sunnier part of the cosmic garden. The chances of all world governments
agreeing on any course of action being very slim indeed.

Perhaps the most interesting implication of this suggestion is what it means
for the human race as a whole. The Russian astronomer Nikolai Kardashev
suggested that civilisations could be classified into four groups of which
ours is a type 0 civilisation, struggling for survival on a single planet
that we can't control. The knowledge and the ability to modify the
configuration of a planetary system to create a more hospitable and
efficient environment is one of the criteria for a type II civilisation.
Shifting planets around in a game of cosmic billiards being an ingenious
alternative to the construction of a Dyson sphere. We now have the knowledge
and the ability, all we lack is the impetus. In short it appears the human
race has just been promoted.

____________________
Dr Matthew J. Genge
Researcher (Meteoritics)
Department of Mineralogy, The Natural History Museum
Cromwell Road, London SW7 5BD, UK.
Tel: Int + 020 7 942 5581
Fax: Int.+ 020 7 942 5537
email: M.Genge@nhm.ac.uk
Staff internet page http://www.nhm.ac.uk/mineralogy/genge/genge.htm

==============
(8) A BETTER UNDERSTANDING OF DR. SIMONENKO'S POSITION

From Worth Crouch <doagain@jps.net>

Dear Dr. Peiser,

I am thankful Dr. Vadim Simonenko replied to my inquiries about difficulties
I had in understanding Russian ideas and projections on asteroid and
comet/Earth impacts.  I was also pleased that E.P. Grondine in the following
article explained some difficulties he had encountered with Russian
publications.  I concur that another persons language can often be
misunderstood. Even Voltaire wrote, "Sometimes a man has nothing more to say
and yet is not persuaded."

After reading Dr. Simonenko's reply to my questions I now understand that he
doesn't propose some of the messages I concluded from the SpaceDaily article
that was reproduced. I had the impression that Russian scientists thought
all the NEO had been discovered. In fact in his reply to me he writes about
global-scale impactors, "There is the hope that the main numbers of them
will be discovered before one of them can terminate human existence"

As far as the threat of Tunguska size asteroids and upwards to about 300
meters (pardon the American spelling) I think Dr. Simonenko made it clear
that they do present a considerable threat. Furthermore, he elaborated on
the size/threat capabilities of different asteroids and I am secure in the
knowledge that he is aware of the potential of impact devastation.

Furthermore, even though Dr. Simonenko was reported to have said, " . .
technology would be able to cope with any danger by finding the hazardous
object in space and by adopting measures able to prevent its impact with
Earth." I understand from his explanation that he was speaking about mankind
's technological future.  However, a catastrophe like a Shoemaker-Levy
9/Earth collision would probably be devastating. Especially when Dr.
Simonenko writes, "Yes, it is possible that such a large-scale event can
also happen to our planet. But having even the unexperienced technology
which exists now, the danger will essentially be discovered earlier."

The final question that Dr. Simonenko answered revolved around his saying,
"But global catastrophes occurred only once every 100,000 to one million years, with
consequences ranging from degradation of the human race to its total
elimination." I answered his quoted belief by writing, " . . . the
scientific community only recently deduced the 1908 Tunguska explosion
resulted from as asteroid impact and scientists were on that sight almost
immediately. Furthermore, only in that last 30 years has the credibility of
global catastrophes such as asteroid/comet impacts and massive volcanic
eruptions been accepted in the scientific community as worthwhile theories
for ecosystem changes. Therefore, I find it rather presumptuous to assign
credibility to prehistoric data that at best only approximated fractionally
what may have actually occurred. Furthermore, when was the Earth's last
great asteroid collision? I don't think Vadim Simonenko or anyone has the
data to enable them to forecast an asteroid or comet Earth collision with
any certainty. In fact because of the mathematical concept of chaos, even
rainy weather forecasting is imperfect. All that is certain is that it will
happen." After commenting correctly on the philosophical nature of much of
my response Dr. Simonenko answered, "As for randomness in space, it is a
deficiency of our knowledge."

The fact is that understanding randomness in space, it is a deficiency of
our knowledge and that deficiency has precisely been my point in questioning
the Russian rational that confidently predicts, " . . . global catastrophes
occurred only once every 100,000 to one million years . . ." If Dr.
Simonenko and I can agree that mankind doesn't have the data, and may not
ever have enough to predict the chaotic randomness of space then we should
agree that there might not be many generations left to prepare Earth's
defense for an unexpected collision. Moreover, it is just a matter of time,
and mankind's deficient ability to understand randomness in space, until a
space defense is overwhelmed. Consequently, we should not only defend
ourselves as quickly as possible, but prepare to construct a place in our
solar system where we can disperse our species and transport the symbiotic
life that is essential to our existence.

Sincerely,

Worth F. Crouch
  (Talako)

==========
(9) PLANETARY DEFENSE

From Andy Smith <astrosafe@yahoo.com>

Hello Benny and CCNet,

We enjoyed the Planetary Defense Special and the associated
Simonenko/Zaitsev/Crouch dialogue, which was enhanced by Ed Grondine. It is
refreshing to talk about the defensive specifics of this important challenge
and such positive dialogue is great.

We have been impressed, for some time, with the capabilities of the
Zenit/Phobos (ZP) system, as a first-line asteroid/comet planetary
protection system and we want to see plans developed to use such systems,
quickly, should we have an asteroid/comet emergency (ACE). Another
first-line system would be the US Delta (Boeing) with a Clementine Class
spacecraft (CLEMENTINE, NEAR, DEEP IMPACT, DEEP SPACE 1, etc.).

We are now classifying the candidate protective systems in 3 groups, based
on their payload capacity. The Class 1 Systems can carry spacecraft weighing
1 or 2 tons (deflection energies in the 1 or 2 megaton range). The Class 2
systems can carry spacecraft in the 5 ton range(5 megatons or so). Class 3
systems can carry double-digit payloads and deflection devices.

We want to encourage our Russian colleagues to design, now, as much as
possible of the hardware and software necessary to make this ZP Asteroid
Deflection System (ZPADS)work...so that it could be employed quickly, in an
emergency (few days or weeks, instead of months to years). We are trying to
get the US engineering organizations to do the same thing.

It is especially important to examine all of the issues having to do with
the mating and operation of the deflection devices....including, of course,
all of the safety considerations.

One of the objectives of the Planetary Protection Alliance or Association
(PPA) will be to promote this kind of contingency planning.

Early-Warning Status

The world-wide average NEO discovery rate was at the single-digit level for
most of the 20th Century. It moved up to double digits in the last decade or
so and to 3 digits, in the last 3 years....thanks to LINEAR.

Most of the major facilities are now completing major upgrades (SPACEWATCH,
LONEOS, NEAT, CATALINA) and Bisei is coming on-line. We would like to see
our Russian colleagues join in this great race.

We are hoping the global discovery rate can reach the 4 digit output level
before 2005 and that we will have at least one orbiting asteroid telescope
in operation, in this decade. If we could find 1,000 new NEO per year, we
could complete most of the hunt (for the 100,000 or so NEO, in this
Century). 3,000 discoveries per year would bring the total required
discovery time down to a few decades.   

The limiting factor, for the US asteroid hunting facilities, seems to be
restrictive operating budgets and we are appealing to NASA and the Congress
to see that the annual national asteroid/comet telescope budget is
increased, this year, to at least $7 million (or double the present level).

It is our impression that the $10 million annual funding level was promised,
in the mid-90's, but only about $3 million per year has been delivered. We
feel this is a very small price to pay for planetary security....and
adequate NEO data is the key to a viable planetary defense progam. At
present, it seems only LINEAR has an adequate operating budget.

There is a detailed discussion of this issue on the Web. It is associated
with the 1998 Congressional Hearing (Space Science Subcommittee) and you can
find that on the NASA/Ames Asteroid Hazard Home Page and at
http://www5.onramp.net/~binder/congmethaz.html

We are also optimistic that the Japanese and United Kingdom programs will be
adequately funded.

The 4 digit annual NEO discovery rate is well within our grasp....all we
need are modest increases in the operating budgets of these key facilities.

If all of the concerned countries would build and staff at least one small
automatic terrestrial asteroid hunting facility (and we could couple this
with an orbiting system), we could reach the high 4 digit NEO discovery
level and complete the critical basic data collection effort, in a few
decades.

Global Planning and Policy Development

Many of the needs identified by Drs. Simonenko and Zaitsev are very
important. We want to discuss some of them and especially the international
treaty needs in PPA workshops and report back to the CCNet.

Request for Russian Graphics

If it is possible to post some briefing graphics of the Zenit/Phobos concept
and the Space Observational Segment (SOS) on the SPACE SHIELD Web site, we
would like to study them and present the concepts to others, as part of our
educational/informational outreach
effort.

Cheers

Andy Smith

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