PLEASE NOTE:


*

CAMBRIDGE-CONFERENCE DEBATE, 26 March 1998
------------------------------------------

During the last couple of weeks, the number of comments by list
members sent for circulation on the CCNet has considerably
increased. While I and many other list members appreciate this
demand for enlightening debates and discussions, others might not
find them of great interest or importance to them. Should you be
such a member who wishes to receive ONLY the CC DIGEST (and not the
additional CC DEBATE), please be so kind and let me know.

Benny J Peiser

=======================
(1) NEO DEFLECTION SYSTEM FAR TOO DANGEROUS TO DEVELOP
    Alan W. Harris <awharris@lithos.jpl.nasa.gov>

(2) WEST TEXAS CRUDE
    Duncan Steel <dis@a011.aone.net.au>

(3) WHAT ARE THE PHYSICS & METEOROLOGY BEHIND 'JOSHUA' EVENT?
    Jonathan Shanklin <jdsh@mail.nerc-bas.ac.uk>


===================
(1) NEO DEFLECTION SYSTEM FAR TOO DANGEROUS TO DEVELOP

From: Alan W. Harris <awharris@lithos.jpl.nasa.gov>

Dear Benny,

Re. the comments from George Wetherill, passed on to you by David Morrison,
I too am skeptical if an impending collision by an asteroid could be "a
wonderful thing." I worry that if something like 1997 XF11 had played
out where the error ellipse continued to shrink down close to the
Earth, so that we could certify that the object would pass only a few
radii away from the Earth, but we could at the same time certify that
there was no real chance of an impact, we would nevertheless see the
folks who brought you Star Wars casting just a shadow of a doubt on our
celestial mechanical predictions, and would be urging a massive program
to deflect or destroy it "just in case."  This kind of stupidity is not
exactly my idea of "a wonderful thing, inspiring the nations of the
Earth to work together to save the planet," that George suggests, but I
am sure that is the kind of hype that would be used to sell the
program. I am quite sure that such arguments would prevail at a level
of risk far below the level at which they are warrented; the only
question is, how low? I would venture a wild guess that a factor of a
thousand is about right -- that is, if we were to live so long, we
would fall victim to the development of such a deflection scheme about
a thousand times more often than one would really be justified, or
turned around the other way, the odds that we will be peddled a
deflection system when one is not rationally called for is about 1000 to
1 more likely than that the discovered object really poses enough of a
threat to call for such action.

With regard to the remarks by Farinella, non-nuclear schemes might be a
practical way to divert the mischief of those who would "protect" us in
advance of proven need, if we are politically unable to keep them from
"doing something."  But if a real threatening object were to be discovered,
I think most of the world's population would be happy to go with the most
expedient solution rather than tinkering with solar sails and other such
"green" options.

Cheers,

Al

====================
(2) WEST TEXAS CRUDE

From: Duncan Steel <dis@a011.aone.net.au>

Meteorite fall in West Texas story.

>An astronomer at the McDonald Observatory theorized that the meteorite
>could have contained copper among its metallic ores, explaining the
>greenish tint to its glow as it passed over Midland. 

Why, just because church roofs are green? For high altitude meteors the
green light often reported is, I believe, due to an atomic oxygen
transition.  I do not have enough information about this fireball to
make any further comment about the light emission.

>Monahans is about 60 miles southwest of Odessa.

...which is of course the location of the first definitely-proven
terrestrial impact crater, named for the town.  It became accepted as an
impact scar in the 1920's due to its association with meteoritic iron.
Although Meteor (Barringer) Crater had been suggested as being an impact
crater earlier, it took a long time for this to be accepted by any but a few
'crazies.'

Duncan

====================
(3) WHAT ARE THE PHYSICS & METEOROLOGY BEHIND 'JOSHUA' EVENT?

From: Jonathan Shanklin <jdsh@mail.nerc-bas.ac.uk>

Perhaps someone (the writer ?) would care to explain the physics and
meteorology that lies behind this curious paragraph:

> In the end it seems more likely that what happened is that the
> disintegration of a large meteoroid of the Sikhote Alin class released a
> large amount of kinetic energy into the atmosphere ("stones") ; this
> heated air came into contact with particles at the super cold
> temperature of space, producing hail ("hailstones").

A meteorite shower will certainly release energy into the atmosphere, but the
surface of the stones is warm due to frictional heating.  Most breakups also
occur at high altitude where there is insufficient water vapour to produce
clouds never mind hail. A major impact could possibly generate enough
convection in the lower atmosphere to create thunderstorm activity, but why not
use Occam's razor?

Jon Shanklin
j.shanklin@bas.ac.uk
British Antarctic Survey, Cambridge, England
http://www.nbs.ac.uk/public/icd/jds



*

CAMBRIDGE-CONFERENCE DIGEST, 26 March 1998
------------------------------------------

"But if a true comet should appear in the heaven itself or
an earthquake should ensure, then it would be time for us
astronomers along with the politicians to sharpen our
pens."

(Johannes Kepler, prognostic calendar for 1618)


(1) WHY I BELIEVE NASA WAS WRONG TO JUMP THE QUEUE
    Benny J Peiser <b.j.peiser@livjm.ac.uk>

(2) THE TRUTH ABOUTH THE SMOKING ASTEROID
    Paolo Farinella <paolof@keplero.dm.unipi.it>

(3) PLANETARY SOCIETY HONORS GENE SHOEMAKER
    Ron Baalke <BAALKE@kelvin.jpl.nasa.gov>

(4) NEXT TIME YOU SEE AN ASTEROID, WHY NOT TRY IMPROVED SOFTWARE
    TO FIND OUT ITS DESTINY?
    Andrea Milani Comparetti <milani@copernico.dm.unipi.it>

(5) IMPACT RATE ON MOON: 815 LUNAR IMPACTS IN 3 YEARS INCLUDING
    THREE REALLY BIG ONES
    Peter Grego <PeterGrego@compuserve.com>

=================================
(1) WHY I BELIEVE NASA WAS WRONG TO JUMP THE QUEUE

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

One of the most unfortunate actions taken during the 1997 XF11 events
two weeks ago was the hasty, and may I dare say rather ill-considered
decision by NASA to jump the queue and not to let the IAU release
Eleanor Helin's 1990 observational data of asteroid 1997 XF11 to the
press. While this rash move was successful in reassuring a rather
asteroid-shoked public, it inevitably created the impression of
divisions and disagreement - if not incompetence - within the
astronomical community. Obviously, a more considered and co-ordinated
press release by NASA & the IAU could have prevented this damaging
imprint.

It was just a question of time that parts of the media would start
exploiting this apparent mis-management in order to further cement the
false impression of disunity or even cover-up when in fact there was
general agreement among all NEO researchers involved. The following
column by FLORIDA TODAY's Billy Cox demonstrates just how damaging the
result of this particular mis-handling has been.

There are quite a number of important lessons to learn from these
events and about how to handle a similar situation in the future. I
hope that this debate and re-assessment will take place sooner rather
than later.

Benny J Peiser

=========================
(2) THE TRUTH ABOUTH THE SMOKING ASTEROID

From: Paolo Farinella <paolof@keplero.dm.unipi.it>

Dear colleagues, have you seen this? It's amusing but...

------

March 20, 1998

THE TRUTH BEHIND THE SMOKING ASTEROID

By Billy Cox
A FLORIDA TODAY column

CAPE CANAVERAL, Fla. - You can smell it in the air - the special
prosecutor's office is getting close to a done deal. Investigators are
now awaiting DNA tests from Mary Kay Letourneau's zygote that could
provide smoking-gun linkage to the Oval Office. Negative results will
lead to impeachment proceedings on the grounds that a 14-year-old boy
was corrupted into licentious acts from watching the president issue
embarrassing sex-scandal denials on TV night after night.

But with the chief executive insulated by his It's-The-Economy-Stupid
Teflon, investigators are hot to trot on their most productive lead
yet. It surfaced last week. Here's our Asteroid Recap For Idiots:

Wednesday afternoon, March 11. The prestigious International
Astronomical Union issued a stunning news bulletin. A mile-wide
asteroid called 1997 XF11 was set to streak between here and the moon
on Oct. 26, 2028. Projected trajectory: 30,000 miles from Earth. But
the calculations were skewed by a 180,000-mile margin of error.
Murphy's Law, etc., etc.

Jack G. Hills, asteroid expert at Los Alamos National Lab: "It scares
me. It really does. An object this big hitting the Earth has the
potential of killing many, many people."

It looked like Dinosaurville for Homo sapiens. Ancient squabbling
cultures united in the choking fallout of a common destiny. The
privileged and the powerful eating dirt with peons and winos.
Earthlings hadn't been bonded by this kind of leveling euphoria since
Apollo 11.

The engines of the entertainment economy were the first to throttle up.
"Armageddon" producers, anticipating a summer-blockbuster windfall from
their Hollywood asteroid, began reworking final edits around the News
Peg From Heaven. "Deep Impact" promoters were caught flat-footed -
their storyline hinged on a comet strike, not an asteroid. But
screening surveys indicated the distinctions were irrelevant, and "Deep
Impact's" box-office prospects looked solid.

On Capitol Hill, legislators and defense contractors were high-fiving
and chicken-dancin' in the bathrooms over space-shield R&D. They
stripped down to their Speedos and prepared to dunk each other in a
30-year supply of pork-barrel grease, their ritual mating cries echoing
like magpies' laughter down the corridors of power - "Jobs! Jobs!
Jobs!"

Not even during the Reagan heyday did consumers have any confidence in
SDI's ability to protect the West from incoming fireballs. Consumers
celebrated 1997 FX11 for different reasons. Liposuction and high-fiber
diets seemed immaterial; cleaning the environment for future
generations, ridiculous. Within hours, Detroit reported a run on
gas-guzzlers. Big Three execs scheduled summit talks to abolish
catalytic converters.

Switchboards at seminary schools were jammed with queries about growth
opportunities; publishing houses were jarred by resupply orders on
religious tracts. FX11 had something for everyone. When the NYSE closed
that afternoon, liquor futures were percolating at New Year's Eve
levels. Supermarket retailers reported junk-food shortages. Property
values in Montana and Idaho jumped 7 1/2 percent by sunset.

In short, FX11 was triggering an economic boom that was about to make
Wall Street's raging bulls of the mid-'90s look like manatees in the
Sahara. And then, a funny thing happened. On March 12, FX11 changed
course.

Astronomers at NASA's Jet Propulsion Lab reported that - ahem - the IAU
boys were a little too optimistic. JPL released new data showing the
asteroid wouldn't hit Earth after all - the thing was going to miss by
whopping 600,000 miles.

And just like that, the story was over. Or so it seemed.

This week, a source close to the investigation revealed that grand jury
subpoenas have been issued to high-level IAU officials. The Whitewater
prosecutor is apparently investigating the political makeup and funding
sources of the IAU, which made its announcement just days before
Kathleen Willey aired her shocking "60 Minutes" testimony. If, as the
independent counsel suspects, the IAU knowingly disseminated false and
diversionary information in order to manipulate the economy and - by
extension - the president's ratings, criminal indictments are
inevitable. Note: The preceding material may or may not be accurate.
Either way, this corner welcomes the opportunity to go on national TV
and chit-chat.

Billy Cox's column runs every Friday. He can be reached at 242-3774, or
FLORIDA TODAY, P.O. Box 419000, Melbourne, FL 32941-9000.

(c) 1998 Forida Today

=====================
(3) PLANETARY SOCIETY HONORS GENE SHOEMAKER

From: Ron Baalke <BAALKE@kelvin.jpl.nasa.gov>

Planetary Society Honors Eugene Shoemaker with Comet and Asteroid
Discovery

Grant Program Named for Astronomer Shoemaker Supports Searches for
Potentially Dangerous Near-Earth Objects

One year ago today, this web site announced that the Planetary Society
had launched its Near-Earth Object (NEO) Grant Program to help discover
the comets and asteroids known to be in our planet's celestial
vicinity. Since then, this ongoing program has been dubbed the Gene
Shoemaker Near-Earth Object Grants -- to honor the late comet and
asteroid discoverer -- and the program has given $35,000 to researchers
from around the world who search for asteroids and comets with orbits
close enough to Earth to pose a potential hazard to our planet.

The first four recipients of the grants are now putting their grants to
work in NEO detection efforts in the United States, Russia, and
Australia.

In the US, Walter Wild in Chicago, Illinois, and Bill Holiday in Corpus
Christi, Texas lead searches that involve amateur astronomers. Wild, an
astronomer at the University of Chicago, leads a group of amateur
astronomers who are conducting a NEO search from Yerkes Observatory in
Wisconsin. Amateur astronomer Holiday is using his grant to upgrade his
home-built rotating roof observatory.

Kirill Zamarashkin is the project coordinator for a joint
Russian-Ukrainian search program at the Crimean Astrophysical
Observatory. This research team has used its Gene Shoemaker grant money
to help construct the first element of an automatic complex to search
for NEOs.

Based in Loomberah, New South Wales in Australia, Gordon Garradd is
using his Gene Shoemaker NEO Grant to complete a 45-centimeter
(18-inch) Newtonian telescope and to acquire a larger, higher-grade
imaging sensor (a CCD, or charge coupled device).

A recent report of Earth's impending close encounter with an asteroid
(featured in an earlier headline article on this web site) emphasized
the importance of detecting the comets and asteroids whose orbits might
intersect Earth's. Astronomers estimate that there are several thousand
NEOs larger than one kilometer and 150,000 to perhaps 100 million
larger than 100 meters in size.

While various astronomical groups and NASA advisory committees have
made strong recommendations to accelerate discovery of these asteroids,
government support for NEO search programs remains very modest. Thus,
the Planetary Society's Gene Shoemaker Near-Earth Object Grants help
fill this funding gap.

The Planetary Society launched its Near-Earth Object Grant Program to
increase the rate of discovery and to permit wider participation by
amateur observers; observers in developing countries; and professional
astronomers who, with seed funding, could greatly increase the
potential of their programs to contribute significantly to the search.
The Society accepts applications for these grants continuously.

To apply for a Gene Shoemaker Near-Earth Object Grant, read the
guidelines and fill out the application form, which are provided on
this web site:

http://planetary.org/NEO/neo-guidelines.html

========================
(4) NEXT TIME YOU SEE AN ASTEROID, WHY NOT TRY IMPROVED SOFTWARE
    TO FIND OUT ITS DESTINY?

From: Andrea Milani Comparetti <milani@copernico.dm.unipi.it>

I believe this announcement [attached] could be of interest for the
people in your mailing list. Next time they could be able to compute
the closets approach by themselves, rather than believeing what the
media say.

Andrea Milani
Dipartimento di Matematica
Via Buonarroti 2
56127 PISA ITALY
tel. +39-50-844254 fax +39-50-844224
E-mail: milani@dm.unipi.it
WWW: http://adams.dm.unipi.it/~milani


Dear OrbFitters and dear friends,

This message announces a new and significantly improved distribution of
the public domain software OrbFit.

The software can be obtained at

ftp://copernico.dm.unipi.it/pub/orbfit

This software system has been developed by a consortium including the
groups led by A. Milani (Pisa University), M. Carpino (Astronomical
Observatory Milano/Brera), K. Muinonen (Helsinki Univesrity) and Z.
Knezevic (Astronomical Observatory Belgrade). The purpose is to make
available to observers of asteroids (and comets) an easy to use but
accurate and reliable software to compute preliminary orbits,
ephemerides, improved orbits (by differential corrections),
identifications, and other auxiliary functions, to allow the processing
of astrometric observations and the planning of observational campaigns
(typically to recover lost objects).

The main improvements in the current version 1.6.0, with respect to
the previous 1.5.1, include:

1) capability to input automatically orbital elements in widely used
formats, such as MPC-Asteroids and Lowell Observatory astorb.dat; these
formats are auto-detected.

2) increased reliability and portability, due to tests performed with 6
different compilers, one syntactic checker, and 3 different versions of
JPL ephemerides. Also to more structured software and safer programming
practices (e.g. IMPLICIT NONE).

3) DOS version, which can run on low cost PC (the disribution includes
exectutables, no need for compilers).

4) revised Everhart propagator (support by G. Valsecchi is acknowledged).

5) unified standards, file formats and control logic between the two
main programs ORBFIT (batch mode) and FITOBS (menu driven interactive).
Now also FITOBS includes the Gauss preliminary orbit determination.

Although the software has been deeply changed, the new version has gone
back to the 'look and feel' of the original OrbFit1.0 (that is, the
software written by Karri Muinonen), e.g. in the possibility for the
user to perform both manual and automated transformations to the
'residuals and weights' files (RUNNAME.orw and RUNNAME.frw for ORBFIT
and FITOBS respectively). This allows fine tuning of the orbital fit,
suitable for the professional user, as well as automatic operations
suitable also for the less experienced users. Thus the orbit
determination and improvement task is quite complete.

The main limitations remaining are:

1) although some progress has been done on the online hypertext user
manual, still it is only a skeleton, and we have to write much more to
make it really informative, especially for the novice user.

2) the observation planning task is very incomplete, and new functions
have to be added.

3) the identification task is incomplete, pending verification of the
performance of the new algorithms, which will be included in the
distribution only when reliably tested.

For the future releases we shall be working on these three points, plus
on an online help system, a WINDOWS95 version, and additional
preliminary orbit capability.

Copyright (C) 1997 Andrea Milani, Mario Carpino, Karri Muinonen,
Zoran Knezevic

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA

To contact us:

milani@dm.unipi.it
carpino@brera.mi.astro.it,
karri@gstar.helsinki.fi,
zoran@aob.bg.ac.yu,

========================
(5) IMPACT RATE ON MOON: 815 LUNAR IMPACTS IN 3 YEARS INCLUDING
    THREE REALLY BIG ONES

From: Peter Grego, Lunar Section Director, Society for Popular
Astronomy <PeterGrego@compuserve.com>

Dear Dr Peiser

In reply to, and to expand on impact matters lunar....

1. A 12th Century Minor Asteroid Impact on the Moon's far-side?

The supposed AD 1100 lunar impact mentioned by Simon Jeffery and David
Morrison I think refers to a remarkable event in AD 1178 chronicled by
Gervase, a 12th century monk whose chronicle is preserved in the library of
Trinity College, Cambridge. On 18 June (old calendar) in the year 1178, a
group of men at Canterbury in England were admiring the beautiful
four-day-old crescent Moon on that warm summer's evening, Gervase reports
them to have been startled by "a flaming torch" which suddenly appeared at
the lunar limb, "spewing out, over a considerable distance, fire, hot coals
and sparks." The Moon is said to have "writhed like a wounded snake" and
assumed a blackish appearance shortly after this unprecedented occurrence.

It is now thought by some that the 1178 event was caused by a sizeable
meteoritic impact upon the lunar surface. As such, it was the first of only
two major cosmic impacts to have been observed this millennium - the
other one happened in July 1994 with the impacts of comet
Shoemaker-Levy's fragmented nucleus in the atmosphere of Jupiter. It
is ironic that both the 1178 and 1994 events were situated just past the
limb of the impacted object, making it impossible to directly observe the
site of the impacts at the moment they occurred.

From the rough position of the "flaming torch" described in the chronicle,
Jack Hartung of New York University in the 1970s worked out that the impact
site lay at around 45  north and 90  east. Looking at photographs taken by
spacecraft in lunar orbit, the site became seemingly obvious - a bright,
fresh-looking 20 km diameter crater called Giordano Bruno, situated just
past the lunar limb (36 N, 103 E) and surrounded by a prominent system of
rays. Some of these rays actually extend past the mean limb around onto the
near-side, so they are theoretically visible through binoculars and
telescopes. Bruno and its rays may represent the newest major topographical
features on any body in the solar system which are likely to be permanent.

I have tried looking for Bruno's rays - binoculars are best suited to this
task. Indeed, on viewing with a good lunar libration and phase there is
some limb brightening on the northeast edge of the Moon, and some faint
streaks on the dark Mare Crisium that may actually represent the Bruno
ejecta system.

2. Lunar Impacts

High temperatures are formed at the lunar surface when fast-moving objects
impact with the Moon, converting kinetic energy to heat. Some of the
short-lived flashes which have been telescopically observed through the
centuries are likely to have been caused by small meteoroidal impacts.
Material thrown up by the impact would form into an expanding shell of dust
and rock which may be visible, especially if the focus of impact happens to
lie just beyond the terminator and the column of ejecta climbs high enough
to be illuminated by the sun. However it has not been proven that any TLP
flash site has ever yielded a new crater which has been detected from the
Earth.

The most credible telescopic observation of a lunar impact seems to have
been that of the 501 kg spaceprobe Luna 5 on 12 May 1965 as it smashed into
Mare Vaporum (31S 8E). According to Keneth Gatland (in Robot Explorers,
Blandford: 1972) a temporary (10 minute) cloud of "lunar dust" measuring
225 x 80km was reported by astronomers at the German observatory at
Rodeswich. The resultant crater is too tiny to be resolved with Earthbound
instruments.

3. Moon impactors detected by Apollo seismometers

The four Apollo lunar seismometers detected tremors in the Moon's crust.
Some of the vibrations recorded were due to deep moonquakes, but many were
likely to have been caused by the impact of meteoroids on the Moon's
surface. It was possible to estimate roughly where each meteoroid had
landed and the force of impact. In a 2.5 year period commencing in 1973,
most of the 815 recorded meteoroid impacts were randomly distributed. But
on three occasions - November and December 1974 and June 1975 - the Moon
seems to have ploughed through a dense barrage of large meteoroids.

Peter Grego
Lunar Section Director, Britain's Society for Popular Astronomy
PeterGrego@compuserve.com

--------------------------------
THE CAMBRIDGE-CONFERENCE NETWORK
--------------------------------
The Cambridge-Conference List is a scholarly electronic network
moderated by Benny J Peiser at Liverpool John Moores University,
United Kingdom. It is the aim of this network to disseminate
information and research findings related to i) geological and
historical neo-catastrophism, ii) NEO research and the hazards to
civilisation due to comets, asteroids and meteor streams, and iii) the
development of a planetary civilisation capable of protecting itself
against cosmic disasters. To subscribe, please contact 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.



CCCMENU CCC for 1998