PLEASE NOTE:


*

CCNet DIGEST 15 July 1998
-------------------------

(1) AS SUSPECTED: JET PROPULSION LABORATORY NOW IN CHARGE OF AMERICAN
    NEAR-EARTH OBJECT PROGRAM & COMMUNICATION WITH AMERICAN NEO
    RESEARCHERS
    NASANews@hq.nasa.gov

(2) NEAR EARTH ASTEROID PROSPECTOR
    Jim Benson <Jim@SpaceDev.Com>

(3) MODERN GLOBAL EFFECTS OF AN AD 536 EVENT
    Leroy Ellenberger <c.leroy@rocketmail.com>

(4) SPACEGUARD UK
    Jonathan TATE <fr77@dial.pipex.com>

(5) K/T IMPACT GLASS FROM HAITI
    R.M. Hough et al., OPEN UNIVERSITY

(6) THE MJOLNIR IMPACT CRATER
    F. Tsikalas et al., UNIVERSITY OF OSLO

================
(1) AS SUSPECTED: JET PROPULSION LABORATORY NOW IN CHARGE OF AMERICAN
    NEAR-EARTH OBJECT PROGRAM & COMMUNICATION WITH AMERICAN NEO
    RESEARCHERS

From NASANews@hq.nasa.gov

Donald Savage
Headquarters, Washington, DC                        July 14, 1998
(Phone:  202/358-1727)

Mary Beth Murrill
Jet Propulsion Laboratory, Pasadena, CA
(Phone:  818/354-5011)

RELEASE:  98-123

NASA ESTABLISHES NEAR-EARTH OBJECT
PROGRAM OFFICE AT JET PROPULSION LABORATORY

       A new program office to coordinate NASA-sponsored efforts
to detect, track and characterize potentially hazardous asteroids
and comets that could approach Earth will be established at NASA's
Jet Propulsion Laboratory (JPL), Pasadena, CA.

       NASA's Near-Earth Object Program Office will focus on the
goal of locating at least 90 percent of the estimated 2,000
asteroids and comets that approach the Earth and are larger than
about 2/3-mile (about 1 kilometer) in diameter, by the end of the
next decade.

       "These are objects that are difficult to detect because of
their relatively small size, but are large enough to cause global
effects if one hit the Earth," said Dr. Donald K. Yeomans of JPL,
who will head the new program office.  "Finding a majority of this
population will require the efforts of researchers at several NASA
centers, at universities and at observatories across the country,
and will require the participation by the international astronomy
community as well."

       "We determined that, in order to achieve our goals, we need
a more formal focusing of our near-Earth object tracking efforts
and related communications with the supporting research
community," said Dr. B. Carl Pilcher, science director for Solar
System Exploration in NASA's Office of Space Science, NASA
Headquarters.  "I want to emphasize that science research
solicitations and resulting peer reviews, international
coordination, and strategic planning regarding future missions
will remain the responsibilities of NASA Headquarters."

       In addition to managing the detection and cataloging of
near-Earth objects, the new NASA office will be responsible for
facilitating communications between the astronomical community and
the public should any potentially hazardous objects be discovered
as a result of the program, Pilcher said.

       JPL was selected to host the program office because of its
expertise in precisely tracking the positions and predicted paths
of asteroids and comets.  No significant additional staff hiring
at JPL is expected at this time.

       A fact sheet describing NASA's research and spacecraft
missions related to asteroids and comets is available on the
Internet at the following address:

    http://www.hq.nasa.gov/office/pao/facts/HTML/FS-023-HQ.htm

                          -end-

====================
(2) NEAR EARTH ASTEROID PROSPECTOR

From Jim Benson <Jim@SpaceDev.Com>

CONTACT:
Jim Benson Shirley Thompson, President
CEO Mike Trueblood, Account Executive
SpaceDev, Inc.         Carl Thompson Associates, Inc.
(619) 684-3570         (800) 665-4200

SpaceDev Reports Three New Teams File Notices of Intent for Proposals
on Near Earth Asteroid Prospector

Notices filed under NASA's MIDEX program, adding to those filed under
Discovery

San Diego, CA -- SpaceDev (OTC BB: SPDV), the world's first commercial
space exploration company, reported today that three principal
investigators filed Notices of Intent (NOI) with NASA for funding under
the Agency's Medium-class Explorers (MIDEX) Announcement of
Opportunity. These notices make them eligible to submit formal
proposals for funding the purchase of insured rides for their
instruments on SpaceDev's Near Earth Asteroid Prospector (NEAP)
mission.

"We are thrilled to have these three highly respected teams demonstrate
their interest in submitting proposals for funding under the MIDEX
program," said Jim Benson, SpaceDev CEO.

The science teams include the University of Iowa, the University of
California at Berkeley and Southwest Research Institute.

The NOI is the first formal step in a process that could result in
government funding for specific experiments or instruments to be carried
on NEAP, currently scheduled for launch in October 2000. 

"Once again, we have been impressed by the degree of support our
mission is finding within our customer base, the scientific community. 
Such response reinforces our belief that there is serious demand for
inexpensive scientific data collected from space. We fully intend to
capitalize on, and even fuel, this demand by producing high quality
science at the lowest current cost."

SpaceDev's commercial price list places the cost of rides for science
experiments or technology demonstrations at $10 or $12 million each,
depending on the type of ride purchased. Mr. Benson noted  that the
filing of an NOI does not automatically result in a proposal to NASA,
and does not guarantee funding for any of the investigations proposed. 
"As we have noted in the past, SpaceDev is responding directly and
substantively to the White House National Space Policy and to Congress
and NASA's call for 'cheaper, better, faster,' space access via the
private sector," said Benson.

The following is the list of principal investigators who filed Notices
of Intent, and their respective mission objectives: 

Dr. Louis A. Frank, University of Iowa.  Mission:  Investigate and
monitor the ambient plasma environment of the asteroid and monitor solar
wind plasmas in an effort to identify evidence of asteroid-plasma
interactions.

Dr. Kevin C. Hurley, University of California at Berkeley.  Mission:
Detect and localize gamma-ray bursts and rapidly communicate that
information to ground-based observers.

Dr. S. Alan Stern, Southwest Research Institute.  Mission:  Conduct
observations of the interaction between solar wind and the moon's
atmosphere, or use an ultra violet photometer to search for surface ice
on the moon.

SpaceDev, the world's first commercial space exploration and
development company, intends to launch the first privately financed
spacecraft to land on another planetary body.  SpaceDev is selling
rides for scientific instruments to governments and companies to
transport their instruments and experiments through deep space to a
near earth asteroid. SpaceDev intends to sell the data acquired by its
instruments as commercial products.  Colorado-based SpaceDev has
offices in San Diego, CA and Washington, D.C.  

Except for historical financial information contained herein, the
matters set forth in this release are forward-looking statements that
are dependent on certain risks and uncertainties  including but not
limited to, such factors as market demand, pricing, and changes in
worldwide economic conditions.

Note:  News releases and other information on SpaceDev can be accessed
at http://www.SpaceDev.com or http://www.ctaonline.com/spdv on the
Internet.

           SpaceDev - NEAP (Near Earth Asteroid Prospector)
-o-  Commercial Space Exploration & Development of Space Resources  -o-
             http://www.spacedev.com  -o-  Info@SpaceDev.Com


======================
(3) MODERN GLOBAL EFFECTS OF AN AD 536 EVENT

From Leroy Ellenberger <c.leroy@rocketmail.com>

Benny Peiser,

In light of the fact that hardly anybody takes Taurid meteor stream
events sans hard impacts as a serious threat (witness the letter
exchange between Paul Weissman and Gerrit Verschuur in the August Sky &
Telescope), perhaps it might be instructive if someone might be
motivated to estimate the effects on 20th century Earth of an event
similar to that in AD 536 when the solar insolation was signifcantly
reduced for 18 months followed by about ten years of poor growing
conditions.

There were successive crop failures in China and the British Isles seem
to have been devastated. There is good suggestive data that multiple
Tunguska events were involved, at least, and there is no evidence for
major volcanic eruptions at that time (which argues strongly for a
cosmic vector with the Taurid stream a most likely source).

I recall a conversation with Victor Clube in 1990 in which he
emphasized that regional disruption from Tunguska-type events would
rapidly precipitate global effects due to the vast interconnectedness
of modern economies. While immediate physical destruction might be
minimal in such a scenario (in contrast to an extinction level event a
la Deep Impact), the dire consequences would nevertheless be vast. One
of his points was that preparedness would best involve acquiring
regional economic independence, which runs counter to the current trend
of globalization of national economies.

I am not qualified to perform such an exercise; but perhaps others who
are might be interested.

Leroy Ellenberger
<c.leroy@rocketmail.com>

====================
(4) SPACEGUARD UK

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

Benny,

You may wish to publish my reply to "Don't be cruel to Americans".

Jay Tate

Thank you for your last, and welcome aboard!  Actually, I am not a
"Dr." just a "Mister".  I am a Major in the British Army, but as my
activities are upsetting the government so much, I don't use my rank!

I too read the Cambridge Conference network, and, as you have seen, I
occasionally contribute.  When you glance at the Spaceguard UK website
you will see that we are the strongest critics of the British
Government’s poor performance. I have brought this to the attention of
the government on a number of occasions, and Sir Crispin Tickell has
recently written personally to the Prime Minister (to whom he is an
advisor).  The very fact that we have had two significant meetings in
the UK on the NEO threat is largely due to the efforts of Spaceguard
UK.

As Duncan Steel will be the first to confirm, the demise of his
programme (originally AANEAS, then Spaceguard Australia) was directly
precipitated by the withdrawal of Australian funding.  In fact, there
never had been funding from the UK, just the provision of facilities
(which had to be paid for).

I will investigate the possible closure of the Nautical Almanac Office.
I was not aware of such a proposal.

I think that it fair to say that the lack of UK news on the CCN is due
to the total lack of news! The British government is doing nothing, so
there is nothing to write about.  On the other hand, Spaceguard UK is
actively campaigning against this lack of action, and is worth writing
about!

I do not believe in “bashing” the USA, and have never indulged in such,
unless something really needs pointing out.  This has only occurred
once, over the question of reporting PHO’s, and I submitted a plan to
David Morrison on the subject.  I also appealed to the NEO community to
stop its internecine and sometimes childish bickering over the XF11
affair, as it was seriously damaging the public credibility of the
subject. Unlike many of the scientists who are actually doing the work,
I interface directly with the public on a daily basis, and I have to
justify what we are doing. This is hard in an atmosphere of conflict
within the NEO community. Some would say, why bother, the public
doesn’t understand.  Well, they had better understand! They pay all of
our wages!  I, and the other members of Spaceguard UK, are trying to
carry the message to the public that this work needs to be done, and
that it deserves a credible level of funding. The response that I
received to my letter has been unanimously positive from the
scientific community, and I hope that we can learn from the affair.

We have to admit that the USA is taking the lion’s share of the
workload in NEO studies, and that is why we are trying to persuade
other governments (specifically the UK) to help.  The UK government may
be asses, but there are a large number of dedicated individuals in this
country who are doing great work.

All the best

Jay Tate

===============
(5) K/T IMPACT GLASS FROM HAITI

R.M. Hough*), I.P. Wright, H. Sigurdsson, C.T. Pillinger, I. Gilmour:
Carbon content and isotopic composition of K/T impact glasses from
Haiti. GEOCHIMICA ET COSMOCHIMICA ACTA, 1998, Vol.62, No.7, pp.1285-
1291

*) OPEN UNIVERSITY, PLANETARY SCI RES INST, MILTON KEYNES MK7 6AA,
   BUCKS, ENGLAND

A microscope study of dark brown impact-produced glasses from the K/T
boundary beds of Beloc (Haiti) has revealed the presence of bubbles
(50-300 mu m in size). A simple experiment to release any enclosed
gases proved positive in some cases and demonstrated pressure in the
bubbles equal to or greater than atmospheric. Stepped combustion
analyses combined with static mass spectrometry was used to verify that
the gas bubbles contained CO2; the content and stable carbon isotopic
composition of this gas was determined along with background
measurements of the glass itself. Results indicated that the brown
Si-rich glasses were heterogeneous in carbon content ranging from
0.007-2.62 wt% carbon, but that sharp releases of gas were afforded at
relatively low temperatures with a carbon isotopic composition up to
-0.8 parts per thousand, similar to that of marine carbonate. The
glasses had been cleaned and acid-etched to remove contamination,
ensuring that any carbon released was indigenous to the glass. The
Ca-rich yellow glasses were analysed in the same way and released
0.265-0.343 wt% carbon with a delta(13)C of -29 parts per thousand,
which is quite different from the Si-rich glasses. The proposed source
crater for these impact glasses is the Chicxulub crater, which has a
pre-impact stratigraphy containing carbonate. Vaporisation of the
carbonate during the impact would have released large quantities of CO2
into the atmosphere, which could have been incorporated into the
glasses as bubbles. Alternatively, the bubbles could have been formed
by degassing of the glasses themselves during cooling. This would
account for the marine carbonate carbon isotopic signature identified
during stepped heating of the high-Si glass. We believe this provides a
further link between the impact glasses of Haiti and the Chicxulub
impact crater although our results for the high Ca glasses proved
inconclusive. Copyright (C) 1998 Elsevier Science Ltd.

==============
(6) THE MJOLNIR IMPACT CRATER

F. Tsikalas*), S.T. Gudlaugsson, O. Eldholm, J.I. Faleide: Integrated
geophysical analysis supporting the impact origin of the Mjolnir
structure, Barents Sea. TECTONOPHYSICS, 1998, Vol.289, No.4, pp.257-280

*) UNIVERSITY OF OSLO, DEPT GEOL, POB 1047, N-0316 OSLO, NORWAY

Gravity, magnetic and seismic traveltime anomalies observed at the
40-km-diameter Mjolnir impact structure reveal a distinct spatial
correspondence with the radially zoned seismic structure. The gravity
anomaly is dominated by a +2.5 mGal, 14-km-wide, centrally located high
superimposed on a 45-km-diameter low that attains minimum values of
-1.5 mGal. The magnetic anomaly field exhibits several local,
low-amplitude anomalies within the +/-100 nT range located towards the
periphery, while seismic mapping of a prominent, originally planar
reflector beneath the structure brings out a central, pull-up
traveltime anomaly on the order of 80 ms. In terms of impact origin,
the integrated geophysical modelling based on the characteristic
bowl-shaped seismic disturbance beneath the structure supports the
differentiation into a central uplift and a peripheral region.
Interaction of several impact cratering processes, such as
impact-induced porosity increase due to brecciation, mass transport
during collapse, and structural uplift, explains the modelled physical
properties associated with the disturbance. The modelling further
substantiates the interpretation of the Mjolnir structure as an impact
crater and demonstrates the incompatibility of alternative geological
origins, such as salt or clay diapirism and igneous intrusions. (C)
1998 Elsevier Science B.V. All rights reserved.

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



CCCMENU CCC for 1998

The content and opinions expressed on this Web page do not necessarily reflect the views of nor are they endorsed by the University of

The content and opinions expressed on this Web page do not necessarily reflect the views of nor are they endorsed by the University of Georgia or the University System of Georgia.