PLEASE NOTE:
*
CAMBRIDGE-CONFERENCE DIGEST, 27 March 1998
------------------------------------------
"Days occur when the House of Commons takes on an 'Alice
Through the Looking Glass' air. Questions and answers
never make contact with each other - or with reality. What
everyone wants to know is what nobody seems to ask.
Ministers pontificate in response to inquiries nobody has
put. [...] On Monday ministers had advised, in a written
answer, that the giant asteroid that dominated the news a
week ago was not, repeat NOT, going to hit the Earth. We
have this on new Labour's authority. The pledge should
perhaps be printed on a sixth coffee mug, to add to the
set of five coffee-mug pledges already marketed by
Millbank Tower: 'Treat More NHS Patients'; 'Smaller Class
Sizes'; 'No Increase In Income Tax Rates'; 'Tough On
Crime'; 'More Jobs For Young People' ... and now: 'No
Collision With Asteroid'.
(Matthew Parris in THE TIMES, 25 March 1998)
(1) SOFT LANDING OF ASTEROID 1997 XF11 IN THE HOUSE OF COMMONS
Jonathan Tate [SPACEGUARD UK} <fr77@dial.pipex.com>
wrote:
(2) 5,000 COMET HALE-BOPP IMAGES
Ron Baalke <BAALKE@kelvin.jpl.nasa.gov>
(3) HYPERVELOCITY IMPACT CRATERING OF CO2 ICE AND IMPLICATIONS
J. Leliwa-Kopystynski et al., UNIVERSITY OF
WARSAW
(4) NEW STUDY ON LOCKNE IMPACT CRATER, SWEDEN
E.F.F. Sturkell, UNIVERSITY OF STOCKHOLM
==========
(1) SOFT LANDING OF ASTEROID 1997 XF11 IN THE HOUSE OF COMMONS
On Monday 23 March, John Battle, Britain's Science Minister,
responded to questions Mr Opik (MP) had raised in the House of
Commons the week before, when asteroid 1997 XF11 made the world's
news headlines. Member of Parliament Mr Opik, the Liberal
Democrat's spokesman for Northern Ireland, is - to our pleasant
surprise - also the grandson of one of Britain's most eminent
cometary astronomers and early NEO researchers, the late Ernst
Opik who, almost three decades ago, was Mark Bailey's predecessor
as the director of the Armagh Observatory.
Jonathan Tate, director of Spaceguard UK, was so kind to forward
Mr Opik's questions and John Battle's rather trivial answers. The
British Government's continuing head-in-the-sand policies
regarding
the NEO threat in general and the cold-blooded termination of NEO
research at the Anglo-Australian Observatory in particular is
perhaps the only reason why I, in moments of foolishness, regret
that Jim Scotti's XF11 changed its mind (and course).
Benny J Peiser
============================================
From: Jonathan Tate [SPACEGUARD UK} <fr77@dial.pipex.com>
---- From the House of Commons, 23 March 1998
Asteroids
Mr. Opik: To ask the Secretary of State for the Home Department
(1) if he will evaluate the reports concerning an asteroid on a
near-collision course with the Earth; and if he will make a
statement;
[34873]
(2) what contingency plans have been made in the event of a
threat
arising from asteroids colliding with the Earth; and if he will
make a
statement; [34874]
(3) what provision exists for international consultation and
co-operation over potential dangers arising from asteroids
striking the
Earth; and if he will make a statement. [34875]
Mr. Battle: I have been asked to reply.
The asteroid 1997 XF11, which was discovered last year, has an
orbit around
the Sun which crosses the Earth's orbit. It will pass by the
Earth in 2028.
Computations made by American scientists earlier this month
indicated that
the asteroid could come within 30,000 miles of the Earth.
However, I
understand that scientists from the American space agency NASA
have now
been able to locate pre-1997 images of the asteroid. This has
enabled
them to calculate a more precise orbit for 1997 XF11 which
indicates
that it will miss the Earth by a much larger margin of 600,00
miles (or
about 2.5 times the distance to the Moon).
The probability of a major impact from an asteroid is extremely
low, but the
emergency services and the emergency planning community in the UK
prepare
for a wide range of disasters and scenarios and they would
respond if the
need arose.
International co-operation and consultation on this issue are
taken forward
in Europe through the European Space Agency and globally through
the United
Nations Committee on the Peaceful Uses of Outer Space (UNCOPUOS).
The UK is
involved in both.
==================================
(2) 5,000 COMET HALE-BOPP IMAGES
From: Ron Baalke <BAALKE@kelvin.jpl.nasa.gov>
March 26, 1998
There is now over 5,000 images of Comet Hale-Bopp on my Comet
Hale-Bopp
home page. This is the world's largest collection of images of
the
comet available on the Internet. I would like to
thank again all of
the people who have contributed their images to share with the
rest of
the world.
http://www.jpl.nasa.gov/comet/
http://galileo.ivv.nasa.gov/comet/
The images cover a period of nearly 3 years for this exciting
comet. The first
image in the archive was taken on July 24, 1995 - the day after
Comet Hale-Bopp's discovery - and the latest image was taken just
a week ago.
Ron Baalke
baalke@kelvin.jpl.nasa.gov
======================
(3) HYPERVELOCITY IMPACT CRATERING OF CO2 ICE AND IMPLICATIONS
J. Leliwa-Kopystynski*), W. Brooke-Thomas, M. J. Burchell, J.C.
Zarnecki: Hypervelocity impact cratering of CO2 ice and
implications
for planetary sciences, ADVANCES IN SPACE RESEARCH, 1997, Vol.20,
No.8,
pp.1577-1580
*) UNIVERSITY OF WARSAW, INSTITUE OF GEOPHYSICS, PASTEURA 7,
PL-02093
WARSAW, POLAND
We present our experimental data for hypervelocity impacts at 5
km s(-1) on compact CO2 ice. We have examinated crater morphology
(depth, diameter, shape and volume) for impacts by stainless
steel
projectiles of diameter from 0.4 mm to 2 mm. Relationships
between
crater and projectile parameters have been derived and
extrapolation to
other projectile sizes is considered By means of comparison of
these
results to impacts on H2O ice as presented in the literature, we
discuss the influence of icy target material on impact crater
records
in the Solar System. (C) 1997 COSPAR. Published by Elsevier
Science Ltd.
===============================
(4) NEW STUDY ON LOCKNE IMPACT CRATER, SWEDEN
E.F.F. Sturkell: Resurge morphology of the marine Lockne impact
crater,
Jamtland, central Sweden, GEOLOGICAL MAGAZINE, 1998, Vol.135,
No.1,
pp.121-127
UNIVERSITY OF STOCKHOLM, DEPARTMENT OF GEOLOGY, S-10691
STOCKHOLM,
SWEDEN
In the Brunflo area of Jamtland, central Sweden, a Cambrian to
Ordovician sedimentary sequence rests on a Proterozoic
crystalline
basement. The area lies just outside the site of the middle
Ordovician
Lockne impact, and it later experienced Caledonian overthrusting.
The
degree of Caledonian tectonization of the Palaeozoic varies, but
an
autochthonous Cambrian and Ordovician sequence apparently occurs
in the
greater part of the area, particularly in the north. The
pre-impact
sedimentary succession is 81 m thick in the autochthon, with the
Middle
Ordovician Furudal Limestone as uppermost member. Brunflo village
is
located just outside the crater, 8-9 km north of its centre, but
the
area was affected by the impact. The impact-generated ejecta and
resurge deposits rest on a surface which cuts the sedimentary
strata at
a low angle. This surface cuts at progressively higher
stratigraphic
levels at increasing distance from the crater. According to
observations in the autochthon the impact generated an erosion
surface dipping 1-2 degrees towards the crater centre. The
sequence of
events that shaped this surface began with bombardment with
high-speed
ejecta closely followed by resurging water. The resurge mixed
ejecta
clasts with the products of resurge erosion to form the resurge
deposits. No rim wall can be traced at the Lockne impact
structure,
probably because a rim wall, if it formed, collapsed in the
modification stage owing to local lithological conditions and
because
the remains of it were completely eroded in the resurge phase. It
is
suggested the rim wall formed in sedimentary strata with
unlithified
clays at their base, and that this clay was unable to support it.
Copyright 1998, Institute for Scientific Information Inc.
--------------------------------
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.