PLEASE NOTE:
*
CCNet DIGEST, 12 March 1999
---------------------------
QUOTE OF THE DAY
"China does not appear to be in the
mood to conclude any kind of
[test ban] agreement with the United
States until things unfold
further," said one Western
diplomat. Until then, he said, there is
likely to be more talk of the need for
nuclear weapons to control
asteroids. (Patrick E. Tyler, June 1996)
(1) CHINA URGES U.N. TO PREVENT ARMS RACE IN SPACE
CNN INTERACTIVE, 11 March 1999
(2) CHINESE SEEK ATOM OPTION TO FEND OFF ASTEROIDS - A REMINDER
THAT
CHINA'S CHARM OFFENSIVE HAS A NUCLEAR SNAG
NEWS ARCHIVE OF NASA'S ASTEROID AND COMET
IMPACT HAZARDS WEBSITE
(3) NASA'S ASTEROID HUNTERS NET A SURPRISE CATCH
Ron Baalke <BAALKE@kelvin.jpl.nasa.gov>
(4) SCHEDULE FOR THE AMATEUR/PROFESSIONAL MINOR PLANET WORKSHOP
Richard A Kowalski <bitnik@bitnik.com>
(5) CRATER ELLIPTICITY IN HYPERVELOCITY IMPACTS ON METAL
M.J. Burchell & N.G. Mackay, UNIVERSITY OF
KENT
(6) MULTIPLE FRAGMENTATION OF COMET MACHHOLZ 2 (P/1994 P1)
Z. Sekanina, CALTECH, JET PROP LAB
(7) SPECTROSCOPIC ANALYSIS OF ASTEROIDS
S. Fornasier et al., DIPARTIMENTO ASTRON,
PADUA
(8) A SPECTROSCOPIC STUDY OF THE THEMIS FAMILY
M. Florczak et al., CNPQ NATIONAL OBSERVATORY,
RIO JANEIRO
=============
(1) CHINA URGES U.N. TO PREVENT ARMS RACE IN SPACE
From CNN INTERACTIVE, 11 March 1999
http://cnn.com/TECH/space/9903/11/china.arms.space.reut/index.html
GENEVA (Reuters) -- China, hoping to head off a proposed U.S.
missile
defense scheme, proposed Thursday that the United Nations
negotiate a
ban on weapons in outer space.
Chinese ambassador Li Changhe said in a speech to the U.N.
Conference
on Disarmament (CD) that preventing an arms race in outer space
had
become a "pressing" issue.
Pakistan's envoy Munir Akram and Egypt's ambassador Mounir Zahran
backed China's proposal to launch formal negotiations on outer
space at
the CD, which has 61 member states.
Diplomats said the U.S. delegation, which did not respond to
China's
speech, was the only member opposed to setting up a CD committee
to
negotiate on outer space. The forum takes decisions by consensus,
meaning Washington can block the proposal.
The hypothetical U.S. Theater Missile Defense system, backed by
Japan,
would be land-based, but probably use space sensors to provide
early
warning of enemy or accidental launches.
China has stepped up denunciation of the scheme. President Jiang
Zemin,
who is to visit Switzerland from March 25-27, is expected to push
the
issue at the CD, diplomatic sources said.
Last week a senior Beijing official warned Washington that any
attempt
to bring Taiwan under the missile defense umbrella would be seen
as
direct U.S. military involvement in Taiwan and encourage
pro-independence forces on the island.
"China has always attached great importance to prevention of
an arms
race in outer space," Li told the Geneva body.
"Given the fact that some country in recent years has been
intensifying
its efforts in developing and testing weapons and weapon systems
in
outer space, and in particular in view of the latest disturbing
developments, prevention of an arms race in outer space has
become more
pressing and present."
Li added: "China believes that the Conference on
Disarmament, as the
single multilateral disarmament negotiating forum, should take
concrete
actions in this regard.
"It should re-establish an ad hoc committee to negotiate and
conclude
international legal instruments on prevention of an arms race in
outer
space."
The CD had a committee on outer space until 1994. Last year it
only
reached consensus to name a special coordinator, but he was
unable to
drum up support for launching negotiations.
Pakistan's Akram said "recent developments" showed the
need for urgent
action. "We believe prevention is better than cure."
The talks, which
end a first 10-week session on March 26, remain divided over its
1999
work program, diplomats say.
The 30 non-aligned member states proposed last month that
negotiations
be launched aimed at total nuclear disarmament.
But the five official nuclear powers -- Britain, China, France,
Russia
and the United States -- have refused to enter full-blown
multilateral
negotiations on nuclear disarmament.
The five argue that the United States and Russia are already
cutting
their huge nuclear arsenals, a process they say should eventually
be
widened to include the other three powers.
But Japan Thursday called on the three smaller official nuclear
weapons
states -- Britain, China and France -- to freeze their nuclear
arsenals
as a contribution to nuclear disarmament.
Japan's ambassador Akira Hayashi also backed launching
negotiations to
halt production of nuclear bomb-making fissile material --
plutonium
and highly enriched uranium.
Copyright 1999, CNN
===================
(2) CHINESE SEEK ATOM OPTION TO FEND OFF ASTEROIDS - A REMINDER
THAT
CHINA'S CHARM OFFENSIVE HAS A NUCLEAR SNAG
NEWS ARCHIVE OF NASA'S ASTEROID AND COMET IMPACT HAZARDS WEBSITE
http://neo.arc.nasa.gov/news/1996/jun/25.html
News Archive: June 1996
CHINESE SEEK ATOM OPTION TO FEND OFF ASTEROIDS
Patrick E. Tyler from Beijing
"The door to peaceful nuclear explosions should not be
closed, at
least not now," the Foreign Minister said. ... China is
arguing that
mankind needs to keep developing "peaceful" nuclear
weapons in case a
giant asteroid is discovered careering through space on a
collision
course with the earth.
China emphasized the asteroid idea but said that nuclear weapons
might also come in handy for other projects.
Some weapons scientists in the United States have argued that
rocket
interceptors should be made ready to nudge doomsday rocks off
course
with a nuclear blast, but they have generally been ignored, with
a
consensus favoring better searches of the heavens to gauge the
potential threat.
"China does not appear to be in the mood to conclude any
kind of
[test ban] agreement with the United States until things unfold
further," said one Western diplomat. Until then, he said,
there is
likely to be more talk of the need for nuclear weapons to control
asteroids.
================
(3) NASA'S ASTEROID HUNTERS NET A SURPRISE CATCH
From Ron Baalke <BAALKE@kelvin.jpl.nasa.gov>
MEDIA RELATIONS OFFICE
JET PROPULSION LABORATORY
CALIFORNIA INSTITUTE OF TECHNOLOGY
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
PASADENA, CALIF. 91109. TELEPHONE (818) 354-5011
http://www.jpl.nasa.gov
Contact: Jane Platt
FOR IMMEDIATE
RELEASE
March 11, 1999
NASA'S ASTEROID HUNTERS NET A SURPRISE CATCH
Astronomers searching for asteroids headed toward Earth have
stumbled
upon a harmless but fascinating discovery -- an exploding star,
also
known as a supernova.
The supernova, named 1999am, is located in a galaxy about 650
million
light-years away. (A light-year is the distance light
travels in one
year, about 9.5 trillion kilometers or 6 trillion miles.)
The star
was unknown to astronomers until it was captured by the camera on
NASA's Near Earth Asteroid Tracking (NEAT) system on February 18.
The NEAT images show the star as it looked just a few weeks after
the
ancient explosion took place.
"We were fishing for salmon, and instead we caught a
whale," said Dr.
Steven Pravdo, project manager and co-investigator for
NEAT. "The
project is designed to look for asteroids and other objects that
might pose a potential hazard to Earth. This supernova
discovery is
an added bonus for astronomers in general."
Supernova 1999am is a "Type Ia supernova," which
means that before
it exploded, it was a white dwarf star in orbit with a companion
star. Near the end of its life, the white dwarf captured so
much
material from its companion that it became too massive to support
itself, and exploded with as much energy as 100 billion
suns. 1999am
is now nearly as bright as the galaxy surrounding it, which is
known
as CGCG 060-009.
NEAT, with asteroid hunter Eleanor Helin as principal
investigator,
has been in operation since December 1995. It uses a large,
sensitive and fully automated charge- coupled device (CCD) camera
mounted on a 1-meter-diameter (39-inch) telescope. The telescope
is
operated by the U.S. Air Force atop Mt. Haleakela on the island
of
Maui, HI.
Since the middle of 1998, NEAT scientists have posted their data
on a
web site through a program called SkyMorph, a collaboration
between
JPL and NASA's Goddard Space Flight Center, Greenbelt, MD.
While the
NEAT project detects Earth-approaching objects by looking for
celestial bodies that move over a period of time, the data can be
used also to hunt for stationary objects that become brighter or
dimmer over time. Thus, the images present a smorgasbord of
astronomical options -- NEAT scientists pick out asteroids,
while
other astronomers select various cosmic morsels through the
public
SkyMorph web site.
"Through SkyMorph, astronomers may find an array of
interesting
objects, including supernovae," said Pravdo, principal
investigator
for SkyMorph. "In this case, we sent our data directly
to the
Lawrence Berkeley National Laboratory in Berkeley,
California. Dr.
Greg Aldering and other scientists with their Supernova Cosmology
Project immediately found 1999am."
Pravdo said the Lawrence Berkeley National Laboratory scientists
found the supernova by comparing images taken in February with
previous NEAT data. They could clearly see a change in
brightness,
indicating the star had exploded and become a supernova.
They
further confirmed their finding with additional observations by
ground-based telescopes. February 18 marked the first time
NEAT
scientists forwarded new data directly to the Berkeley lab, and
as
Pravdo pointed out, "We struck paydirt."
For information and an image of 1999am, go to the following web
site:
http://huey.jpl.nasa.gov/~spravdo/snanima.htm
For more information on the NEAT project go to
http://huey.jpl.nasa.gov/~spravdo/neat.html
Information on SkyMorph is available at the following web site:
http://skys.gsfc.nasa.gov/skymorph/skymorph.html
Dr. Thomas McGlynn is lead scientist for SkyMorph at
Goddard. The
NEAT and SkyMorph projects are managed by JPL for NASA's Office
of
Space Science, Washington, DC.
JPL is a division of the California Institute of Technology,
Pasadena, CA.
================
(4) SCHEDULE FOR THE AMATEUR/PROFESSIONAL MINOR PLANET WORKSHOP
From Richard A Kowalski <bitnik@bitnik.com>
[as posted on the Minor Planet Mailing List <mplist@bitnik.com>]
Hello all.
We have a very full and I'm sure you'll agree, a very interesting
schedule of speakers and presenations for the Minor Planet
Amateur-Professional Workshop.
The current schedule is attached below. Please be aware that some
times
may change, but this is how things are shaping up for April.
I'd like to take this opportunity to thank everyone who applied
for a
Travel Assistance Grant. The winners will be notified by Tuesday,
March
16th.
See you in Flagstaff!!!
Richard
~~~~~~~~~~~~~~~~~~~~
Amateur/Professional Minor Planet Workshop
Lowell Observatory
Friday, April 23, 1999 -- Paul Comba, moderator
8:30-8:40 Robert
Millis Welcome
8:40-9:00 Richard Kowalski A Brief
History of Minor Planet
Research
9:00-9:30 Edward
Bowell Choosing Asteroid
Astrometric
Targets
9:30-10:00 Dennis DiCicco
Where to From Here
10:00-10:30 break
10:30-11:00 Paul
Comba Three Years
of CCD Astrometry in a
Changing Environment
11:00-11:30 John
Rogers Recovering
Asteroids. It's not
there! Now what do I do??
11:30-12:00 Roy
Tucker Searching
for Small Solar System
Bodies: Instrumentation and Methods
12:00- 1:30 Lunch break
1:30- 2:00 Brian Marsden & The
Role of Amateur Astronomers in
Gareth Williams the Work of the Minor Planet
Center
2:00- 2:30 William
Owen Error Sources in
Asteroid Astrometry
2:30- 3:00 John Stansberry KBOs
and Occultations
3:00- 3:30 break
3:30- 3:50 Don
Yeomans Amateur
Astrometric Contributions
in Support of Flight Projects
3:50-4:10 Gordon
Garradd Minor Planet Observing from
Loomberah, Australia
4:10- general
discussion
--------------------------------------------------
Saturday, April 24, 1999 -- Richard Kowalski, moderator
8:30-9:00 Alan
Harris Asteroid
Lightcurve Photometry
9:00-9:30 Arne
Henden Photometric
Techniques for Moving
Objects
9:30-10:00 Charles Wetterer Asteroid
Astrometry and Photometry
& Slavko Majcen at the US Air Force Academy
Observatory
10:00-10:30 break
10:30-11:00 Kenneth Zeigler Astronomical
Research Involving
Junior High and High School
Students
11:00-11:30 Walter Worman CCD
Photometry at the Paul Feder
Observatory
11:30-12:00 Brian
Warner An Automated Program
for
Determining Lightcurves of Asteroids
12:00- 1:30 lunch break
1:30- 1:45 Lawrence Garrett The A.L.P.O.
Magnitude Alert Program
1:45- 2:00 James
McGaha Unfiltered Photometry
of Asteroids
2:00- 2:15 Ian
Griffin Astrometry from
a Public Observatory
2:15- 2:30 John
Briggs Remembrances of
Edgar Everhart's
Solar System Astrometry
2:30- 2:45 Glenn
Snyder The CLEA Toolkit for
CCD Astrometry
2:45- 3:00 Steven Chesley
NOEDyS: an Online Information Sytem
for Near-Earth Objects
3:00- 3:30 break
3:30- 3:50 Richard Kowalski Online
Resources Available to the
Minor Planet Researcher
3:50- general
discussion
--------------------------------------------------
POSTER PRESENTATIONS
L. Bittesini Topic to be announced
John Briggs The Summer Science Program
Richard Davis Minor Planet 1998 KU2: A Possible
Multiple Body
Object
Bob Denny Automated Observing
with Portable Instruments
Bill Dillon Quality Assurance and Control
of Amateur Asteroid
Astrometry
Charles Juels Various Tables (diameter vs H, etc.)
=====================
(5) CRATER ELLIPTICITY IN HYPERVELOCITY IMPACTS ON METAL
M.J. Burchell & N.G. Mackay: Crater ellipticity in
hypervelocity
impacts on metals. JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS, 1998,
Vol.103, No.E10, pp.22761-22774
UNIVERSITY OF KENT, SCH PHYS SCI, UNIT SPACE SCI & ASTROPHYS,
CANTERBURY CT2 7NR, KENT, ENGLAND
The change in crater shape of hypervelocity impacts as a function
of
impact angle has been studied for impacts at 2 and 5 km s(-1) of
millimeter-sized spherical projectiles of cellulose acetate,
aluminum
and stainless steel impacting aluminum, and stainless steel, and
lead
targets. The variation in crater depth, length, and diameter with
impact angle is presented and discussed. While the main
dependence on
impact angle is found to be of a cos theta nature, cases are
found
where the magnitude of the dependence changes at discrete angles
of
impact. This is interpreted as evidence of disruption of the
projectile affecting the final size of the crater. Crater depth
is
found to depend on (cos theta)(n), where n is strongly dependent
on
the projectile density and not the traditionally assumed constant
value of two-thirds. For aluminum impacting aluminum at 5 km
s(-1), n
is found to be near unity. Reproducing the criteria used in
analysis
of crater shape in published work for the Long Duration Exposure
Facility satellite yields a mean density for small particles in
Low
Earth Orbit of 3400 kg m(-3). Normal incidence impacts of
non-spherical projectiles have also been studied and found to
yield
irregularly shaped craters, which can appear as oblique angle
impacts
of spheres. No sensible cuts on crater measurements permit clean
separation of these two types of impacts. Copyright 1999,
Institute
for Scientific Information Inc.
=====================
(6) MULTIPLE FRAGMENTATION OF COMET MACHHOLZ 2 (P/1994 P1)
Z. Sekanina: Multiple fragmentation of comet Machholz 2 (P/1994
P1).
ASTRONOMY AND ASTROPHYSICS, 1999, Vol.342, No.1, pp.285-299
CALTECH,JET PROP LAB,4800 OAK GROVE DR,PASADENA,CA,91109
Discovered in August of 1994, periodic comet Machholz 2 consisted
of
five condensations, A-E, of which D later became double. They
were
lined up along their common heliocentric orbit (with A being the
leading and brightest component) and connected by a trail of
material, suggesting that the comet's nuclear fragmentation was
accompanied by a copious release of large dust particles. The
earliest breakup is found to have occurred in late 1987, similar
to
600 days before the comet's 1989 perihelion, giving birth to
fragment
B and the grand precursor of A. The precursors of A and D and
fragments A and C appear to have originated, respectively,
similar to
5 days prior to and right at perihelion. The last breakup episode
during that same return to the Sun was the separation of E,
probably
from the precursor of D, similar to 600 days after perihelion.
The
division of D into D-1 and D-2 is the only event analyzed in this
paper that occurred one revolution later, in 1994. The
circumstances
and implications of this fragmentation sequence are examined in
detail and predictions are presented for 1999/2000. Copyright
1999,
Institute for Scientific Information Inc.
====================
(7) SPECTROSCOPIC ANALYSIS OF ASTEROIDS
S. Fornasier*), M. Lazzarin, C. Barbieri, M.A. Barucci:
Spectroscopic
comparison of aqueous altered asteroids with CM2 carbonaceous
chondrite meteorites. ASTRONOMY & ASTROPHYSICS SUPPLEMENT
SERIES,
1999, Vol.135, No.1, pp.65-73
*) DIPARTIMENTO ASTRON,VIA OSSERVATORIO 5,I-35122 PADUA,ITALY
In the last year we have started a spectroscopic investigation of
asteroids located in the region of the main-belt between about
2.2
and 3.6 AU. The aim of this work is to study the aqueous
alteration
process which acted in that zone, dominated by low albedo C-type
asteroids, and to compare the spectra of these hydrous objects
with
those of CM2 carbonaceous chondrite meteorites. In fact, the
spectra
of these meteorites reveal features probably due to aqueous
altered
materials on their surfaces. The study of the aqueous alteration
process can give important information on the chemical and
thermal
evolution of the earliest Solar System. More that 65% of the
investigated objects have revealed features suggesting the
presence
of hydrous materials. The comparison of the spectra of the
hydrated
asteroids obtained to date with those of several CM2 carbonaceous
chondrite meteorites seems to indicate that aqueous altered
asteroids
could be the parents of CM2 meteorites. The data have been
obtained
during several observiational runs at the Asiago Observatory with
the
1.8 m tele scope and at ESO-LaSilla with the 1.5 m telescope.
Copyright 1999, Institute for Scientific Information Inc.
=============
(8) A SPECTROSCOPIC STUDY OF THE THEMIS FAMILY
M. Florczak*), D. Lazzaro, T. MotheDiniz, C.A. Angeli, A.S.
Betzler: A
spectroscopic study of the Themis family. ASTRONOMY &
ASTROPHYSICS
SUPPLEMENT SERIES, 1999, Vol.134, No.3, pp.463-471
*) CNPQ OBSERV NACL,DEPT ASTROFIS,BR-20921400 RIO JANEIRO,BRAZIL
We present spectroscopic observations of 36 asteroids, members of
the
Themis family. These observations were carried on at the European
Southern Observatory in the wavelength range 4900 - 9200
Angstrom. Most
of the objects present a spectra similar to C-type asteroids and
some
of them present indicative of aqueous alteration. We discuss the
implications of these results on the formation and evolution of
this
family. Copyright 1999, Institute for Scientific Information Inc.
----------------------------------------
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