PLEASE NOTE:
*
CCNet 85/2001 - 10 July 2001
---------------------------
"We seem to have a problem. Heinrich Waenke and other
cosmochemists
have come to the conclusion that certain types of meteorites
originated from the surface of Mars, most likely as the result of
a
high-velocity impact. But I find it difficult to visualize a
scenario
that can impart a velocity of the order of 10 km/sec to a rock
coming from
such an impact without the accelerating force exceeding the
crushing
strength of the rock. John Michael Williams seems to have
demonstrated
that a gentle acceleration of the rock by a gas cloud is
physically
impossible. Neither of us has a good mechanism for getting
a rock off the
Martian surface with the required velocity. So -- my question to
the
chemists: Could the "Martian" meteorites have come from
Deimos? Or
must they originate from the Mars surface, in which case we may
need
to find some mechanism for a more sustained and gentle
acceleration?"
--Fred Singer, 9 July 2001
"Our generation is the first one in history (well in excess
of 4,000
generations) with a full awareness of the asteroid/comet danger
and the
capability to find the threatening NEOs and to intercept and
deflect
them. That awareness (and capability) places a tremendous
responsibility on our shoulders....and all who share the
knowledge, also
share the responsibility."
--Andy Smith, 10 July 2001
(1) IMPACT SITE CONFIRMED IN PANAMA
Andrew Yee <ayee@nova.astro.utoronto.ca>
(2) ROSETTA'S CONSERT HEADS FOR A REAL COOL VENUE
Andrew Yee <ayee@nova.astro.utoronto.ca>
(3) KILLING POWER OF ANCIENT VOLCANOES
Andrew Yee <ayee@nova.astro.utoronto.ca>
(4) POSTCARD FROM MARS
Andrew Yee <ayee@nova.astro.utoronto.ca>
(5) NEXT SPACE SCIENCE UPDATE: A STELLAR APOCALYPSE AIDS THE HUNT
FOR LIFE
ON OTHER WORLDS
NASANews@hq.nasa.gov
(6) ALL FAULT LINES ARE NOT EQUAL
Andrew Yee <ayee@nova.astro.utoronto.ca>
(7) RESEARCHERS PROPOSE NEW GEOLOGICAL FORMATION THEORY
Andrew Yee <ayee@nova.astro.utoronto.ca>
(8) LIFE IN THE UNIVERSE? IS ANYBODY OUT THERE?
ESA Media Relations <ContactESA@esa.int>
(9) MEN ARE FROM MARS, WOMEN ARE FROM VENUS; BUT WHAT ABOUT
MARTIAN
METEORITES?
Fred Singer <singer@sepp.org>
(10) JULIO FERNANDEZ & THE ORIGIN OF SHORT-PERIOD COMETS
Javier Licandro <licandro@tng.iac.es>
(11) SHOEMAKER-LEVY 9 ANNIVERSARY
Andy Smith <astrosafe@yahoo.com>
(12) QUESTIONS ABOUT CELESTIAL OBJECTS COLLIDING WITH THE EARTH
John Garner <backscatt@worldnet.att.net>
(13) AND FINALLY: ON THE ROCKS
Andrew Yee <ayee@nova.astro.utoronto.ca>
===============
(1) IMPACT SITE CONFIRMED IN PANAMA
From Andrew Yee <ayee@nova.astro.utoronto.ca>
University of South Florida
Media Contact:
Marsha Strickhouser, (813) 974-4014
STORY SOURCE:
Livio Tornabene, (813) 598-4231
June 18, 2001
USF graduate student confirms asteroid site in Panama
TAMPA, Fla. -- In August 1998, Bob Stewart, a retired geologist
from the
Republic de Panama, showed up on the doorstep of USF's Department
of Geology
bearing a heavy knapsack of rocks. Not just any rocks, but
unusual rocks he
recovered near the Panama Canal Zone in the middle of what he
believed to be
a possible asteroid impact site. They were not at all consistent
with the
local geological setting. They showed indications of shattering,
melting and
flow features that were forever frozen in time and marking a
catastrophic
event in the Earth's geologic past.
When seven of those rocks fell in to the lap of Jeffrey Ryan,
USF's interim
chairman of the geology department, he immediately handed them
over to a
young master's student eager to work on anything dealing with
planetary
science, Livio L. Tornabene.
Until then, the site had not been seriously investigated as a
possible
impact site since it had been first discovered in August 1972.
Stewart had
noticed the anomalous circular structure during a survey and
mapping project
in the Panama Canal Zone. He collected samples in 1990 and 1995.
But until
summer 1998, the samples sat undisturbed in his garage.
Tornabene had Stewart's notes and the seven rocks, but knew that
any proof,
if it were indeed an impact site, would probably be microscopic.
"At larger
diameters, there's pretty much nothing left of the impacting
body," he said.
"The asteroid vaporizes and melts upon impact. You could
literally have a
giant gaping hole in the earth, but unless you prove it with
certain
microscopic features caused by intense shock (like shocked quartz
or diamond
formation), you have nothing."
Tornabene, co-investigator Tom Carey and a local guide set out
with maps and
canteens through the rain forest during the heat and humidity of
July. "It
was the worst time of year we could possibly go, considering it
was summer
and still deep into the rainy season," he said.
The trip was an hour and 40 minutes total out of Panama City,
about an hour
to the Gamboa Docks and then west on the Panama Canal about six
and a half
miles on a 15-foot dingy. They spent 12 hours a day for two weeks
searching
and collecting samples. "This structure in the Panama Canal
Zone was eroded
and flooded on the northwest side, a lot more subtle than the one
in
Arizona, which is well persevered in the dry desert climate.
It was covered by dense forest, and battered by the tropical
environment,
which accelerates erosion. It was very difficult to view a
structure and to
find rocks," he said.
He obtained about 30 samples that weighed about 200 pounds. This
time he
found more anomalous rocks bearing all different colors -- light
blue,
green, white, beige and black.
"Since the proof is usually microscopic, you just have to go
to the site,
sample it and look at the structure in great detail," said
Tornabene, who
now calls the site the Gatun Structure because it's located near
the Gatun
Lake.
In May, Tornabene found the proof he was looking for in the form
of
diaplectic glass, which is a purely impact-generated phenomenon.
Tornabene
presented the discovery at the spring meeting of the American
Geophysical
Union in Boston.
Tornabene estimates the actual asteroid was roughly 150 meters in
diameter
-- larger than one-and-a-half football fields -- and traveled at
a minimum
of 25,000 miles per hour -- about the top speed of the space
shuttle. This
site is roughly 2.2 to 3 kilometers or two miles in diameter --
more than
twice the size of the one in Arizona most people are familiar
with. Only 177
known impact structures like it have been identified to date.
"When you look at the moon, you see millions of craters,
especially smaller
ones," Tornabene said. "We've been hit probably 20
times more than the moon.
And yet, we don't see as many at the surface. It's the active,
water-covered
surface of Earth that obscures or obliterates these features and
makes them
very difficult to find.
"We can learn a lot from the smaller ones," he said.
"I've seen some
features in my samples that I haven't seen in literature. It's
interesting
to find a structure like this at all in a tropical setting,
especially with
the erosion rates as high as they are in the tropics."
The rocks that were hit by the asteroid are 20 million years old,
so it's
possible the impact could have occurred 20 million years ago.
Tornabene
wants to send some samples for Argon-Argon dating, a radioactive
method to
resolve the formation age of the impact structure.
The University of South Florida is a metropolitan research
university with
campuses in Tampa, St. Petersburg, Sarasota/Manatee and Lakeland.
With about
35,500 students, USF offers 70 baccalaureate programs and 130
graduate
programs, including the M.D. Last year, its students and faculty
attracted
$171.3 million in research contracts and grants.
=============
(2) ROSETTA'S CONSERT HEADS FOR A REAL COOL VENUE
From Andrew Yee <ayee@nova.astro.utoronto.ca>
ESA Science News
http://sci.esa.int
05 Jul 2001
What is a comet really like? What is its interior like? Could it
be a fluffy
agglomeration of snow and dirt? Or perhaps it is solid all the
way through
like an iceberg encrusted with black organic material? Some have
even
likened it to a chocolate cake with a dark surface overlying a
mixture of
porous and solid material! Identifying the nature of a comet is
just one of
the key questions that ESA's Rosetta mission is intended to
answer, and the Comet
Nucleus Sounding Experiment by Radiowave Transmission (CONSERT)
instrument
on the Rosetta Orbiter and Lander will play a major role in
revealing the
true nature of these cosmic wanderers.
CONSERT has already made its mark by becoming the first of the
scientific
experiments that will fly on the Rosetta Orbiter to be delivered
to Alenia
Spazio in Turin. The remainder of the comet chaser's
state-of-the-art
payload will follow in the coming weeks, paving the way for the
start of the
Orbiter's payload integration phase.
Sounding a comet with radar
CONSERT's mass is limited to only 3 kg, but there is nothing
lightweight
about its mission to gently probe the interior of a comet --
something that
has never before been attempted.
The experiment, built in France and in Germany, will reveal the
internal
structure of Comet Wirtanen's nucleus by using an ingenious radar
sounding
technique. As the Rosetta Orbiter swings around the tiny ice
world at a
distance of less than 30 km, a transmitter on board the
spacecraft sends a
radio 'pulse' towards the comet nucleus at a frequency close to
90 MHz.
The Lander, which is sitting on the far side of the nucleus,
behaves rather
like a mirror. It receives the signal after it has travelled
through the icy
nucleus and transmits a new 'pulse' back towards the Orbiter.
This
re-transmitted signal eventually arrives back at the Orbiter,
where it is
compressed and stored for off-line scientific analysis.
Some 3000 of these measurements will be taken during each orbit
of Comet
Wirtanen. By studying the time delays as the signals pass through
the
nucleus from different directions, the scientists will be able to
estimate
the dielectric constant of the materials inside the comet (a
measure of its
ability to reflect the radio signals and their velocity). They
will then be
able to determine the internal structure (if any) of the nucleus
-- the
denser the material is, the slower the pulse passes through it.
So will it work?
The experiment's principal investigator, Professor Wlodek Kofman
of the
Laboratoire de Planetologie (CNRS-UJF-OSUG) in Grenoble and also
affiliated
with the Service d'Aeronomie (CNRS), France, has been studying
this problem
for many years.
"Based on our current understanding of the composition of
comets, we believe
that electromagnetic waves of the right frequency will pass right
through
the nucleus," said Professor Kofman.
"Obviously, we have to try out the technique on Earth in
order to see if it
works before we launch it towards a comet or planet," he
said. "In 1993 we
actually went to Antarctica to carry out a radar experiment and
we found
that we could successfully deduce the structure inside the
ice."
"We were intending to fly a radar on the Russian Mars-98
mission in order to
measure the thickness of the Martian permafrost," he
continued,
"Unfortunately, the mission was cancelled, so Rosetta will
be our first
opportunity to fly an experiment in space."
"We have recently completed a successful test of the CONSERT
Electrical
Qualification Models on the roofs of the University of
Bochum," he said.
"The two antennae and mock-ups of the Lander and Orbiter
were placed on two
different roofs so that we could characterise the radiation
pattern of the
antennae with a minimum of interference from the ground and
perform the
end-to-end test of the equipment," he explained.
"The 'Lander' was placed on one roof, about 80 metres away
from the
'Orbiter', and we picked up the return signal loud and
clear," said Kofman.
"When we are in orbit around Wirtanen, we should be able to
detect large
structures or layers within the comet, and even recognise
small-scale
irregularities," he added.
One of the great unknowns is the lifetime of the experiment,
since its
success depends on the continued operation of the Rosetta Lander.
"The life of the Lander is expected to be quite short --
possibly only a few
days or weeks," explained Professor Kofman. "If the
Lander survives for a
long time, we will carry out the experiment many times.
Obviously, I would
like it to operate for many orbits!"
The CONSERT instrument was developed by three European
institutes: the
Service d'Aéronomie in Paris; the Laboratoire de Planétologie
in Grenoble;
and the Max-Planck-Institut für Aeronomie in Lindau. Other
contributions
have been made by the European Space Technology Centre (ESTEC) in
the
Netherlands and the University of Bochum.
For further information contact:
Professor Wlodek Kofman
Laboratoire de Planétologie de Grenoble, France
Tel: +33 476 514152
E-mail: wlodek.kofman@obs.ujf-grenoble.fr
USEFUL LINKS FOR THIS STORY
* Rosetta home page
http://sci.esa.int/rosetta/
* Rosetta instruments
http://sci.esa.int/content/doc/e5/2277_.htm
IMAGE CAPTIONS:
[Image 1:
http://sci.esa.int/content/searchimage/searchresult.cfm?aid=1&cid=1&oid=27488&ooid=27694
]
The Rosetta Orbiter swoops over the Lander soon after touchdown
on the
nucleus of Comet 46P/Wirtanen. (Photo courtesy Astrium).
[Image 2:
http://sci.esa.int/content/searchimage/searchresult.cfm?aid=1&cid=1&oid=27488&ooid=27518
]
The mock-up lander antenna during tests on the roof of the
University of
Bochum.
[Image 3:
http://sci.esa.int/content/searchimage/searchresult.cfm?aid=1&cid=1&oid=27488&ooid=27519
]
The mock-up orbiter antenna during tests on the roof of the
University of
Bochum.
[Image 4:
http://sci.esa.int/content/searchimage/searchresult.cfm?aid=1&cid=1&oid=27488&ooid=27680
]
Professor Wlodek Kofman, principal investigator of CONSERT.
Laboratoire de
Planétologie de Grenoble, France.
[Image 5:
http://sci.esa.int/content/searchimage/searchresult.cfm?aid=1&cid=1&oid=27488&ooid=27684
]
Radar tests at Dumont d'Urville, the French station in
Antarctica, showed
that the CONSERT technique works.
=============
(3) KILLING POWER OF ANCIENT VOLCANOES
From Andrew Yee <ayee@nova.astro.utoronto.ca>
New Scientist
http://www.newscientist.com
UK CONTACT:
Claire Bowles, New Scientist Press Office, London
Tel: +44(0)20 7331 2751 or email claire.bowles@rbi.co.uk
EMBARGOED UNTIL WEDNESDAY 4 JULY 2001, 19:00 BST
Ancient volcanoes
VOLCANOES were more destructive in ancient history. Not because
they were
bigger, but because the carbon dioxide they released wiped out
life with
greater ease.
Paul Wignall from the University of Leeds was investigating the
link between
volcanic eruptions and mass extinctions. Not all volcanic
eruptions killed
off large numbers of animals, but all the mass extinctions over
the past 300
million years coincided with huge formations of volcanic rock. To
his
surprise, the older the massive volcanic eruptions were, the more
damage
they seemed to do.
Wignall calculated the "killing efficiency" for these
volcanoes by comparing
the proportion of life they killed off with the volume of lava
that they
produced. He found that size for size, older eruptions were at
least 10
times as effective at wiping out life as their more recent
rivals.
The Permian extinction, for example, which happened 250 million
years ago,
is marked by floods of volcanic rock in Siberia that cover an
area roughly
the size of western Europe. Those volcanoes are thought to have
pumped out
about 10 gigatonnes of carbon as carbon dioxide. The global
warming that
followed wiped out 80 per cent of all marine genera at the time,
and it took
5 million years for the planet to recover.
Yet 60 million years ago in the late Palaeocene there was another
huge
amount of volcanic activity and global warming but no mass
extinction. Some
animals did disappear but things returned to normal within tens
of thousands
of years. "The most recent ones hardly have an effect at
all," Wignall says.
He ignored the extinction which wiped out the dinosaurs at the
end of the
Cretaceous, 65 million years ago, because many scientists believe
it was
primarily caused by the impact of an asteroid.
Wignall thinks that older volcanoes had more killing power
because more
recent life forms were better adapted to dealing with increased
levels of
CO2. Ocean chemistry may also have played a role. As the
supercontinents
broke up and exposed more coastline there may have been more
weathering of
silica rocks. This would have encouraged the growth of
phytoplankton in the
oceans, increasing the amount of CO2 absorbed from the
atmosphere.
Vincent Courtillot, director of the Paris Geophysical Institute
in France,
says that Wignall's idea is provocative. But he says it is
incredibly hard
to do these sorts of calculations. He points out that the killing
power of
volcanic eruptions depends on how long they lasted. And it is
impossible to
tell whether the huge blasts lasted for thousands or millions of
years.
Courtillot also adds that it is difficult to estimate how much
lava
prehistoric volcanoes produced, and that lava volume may not
necessarily
correspond to carbon dioxide or sulphur dioxide emissions.
Nicola Jones reports from the Earth System Processes meeting in
Edinburgh.
New Scientist issue: 7th July 2001
PLEASE MENTION NEW SCIENTIST AS THE SOURCE OF THIS STORY AND, IF
PUBLISHING
ONLINE, PLEASE CARRY A HYPERLINK TO:
http://www.newscientist.com
========
(4) POSTCARD FROM MARS
From Andrew Yee <ayee@nova.astro.utoronto.ca>
ESA News
http://www.esa.int
9 July 2001
Postcard from Mars
When most people go on vacation, they want to forget all about
their jobs.
But ESA physicist-engineer Vladimir Pletser, who develops ISS
payloads and
organizes zero-gravity parabolic flights for the agency, is
taking the
ultimate working holiday. This week, he's off to Mars.
It's not exactly Mars, of course. Manned missions to the Sun's
fourth planet
-- currently the brightest object in Europe's evening skies --
will have to
wait a while yet. Instead, Pletser will be heading for the
Arctic, where
throughout the summer crews of scientists will spend ten-day
stints in a
cramped habitat that closely simulates a Mars lander.
The habitat -- built by the Mars Society with privately raised
funds -- is
on Devon Island, situated at latitude 75 degrees North in
Canada's Nunavut
Territory. The chilly terrain, snow-free in summer, is about as
close an
analogue to the Martian surface as exists on Earth. Obviously,
there is no
way to mimic the Martian surface gravity of just 0.38 g or the
planet's
thin, unbreathable carbon dioxide atmosphere. But the dry, cold,
rocky
desert that is Devon Island meets most other criteria.
The place is big, too: at 66,800 sq km (almost exactly twice the
size of
Belgium) it is the world's largest uninhabited island. Devon
Island also
contains the Haughton impact crater, a 20-km scar on the
landscape gouged
out by a giant meteorite some 23 million years ago, which closely
resembles
similar craters on Mars.
During their simulated visit to Mars, the men and women in each
six-member
crew will have to live and work together in a space not much
bigger than a
camper van. There will be daily EVAs (Extra-Vehicular
Activities), for which
the scientists will have to struggle into "spacesuits"
and exit their
temporary home through an airlock. To add more Martian realism,
communications with "mission control" will be subject
to a 20-minute delay
that matches the lightspeed lag that any real Mars expedition
would have to
contend with. As for links to home, the explorers can hope to
send an email
every 24 hours or so.
"The first goal is to test the feasibility of a Mars mission
with existing
technology," says Pletser. "But we want to do some
science, too." He will be
performing an important geophysics experiment himself: an attempt
to detect
subsurface water by means of seismic waves. Encumbered in an EVA
suit with
limited visibility, he won't find the work easy. But it is
exactly the sort
of task that will face future Martian explorers.
Compared with future Mars astronauts, the Devon Island explorers
will have
things easy. They will be isolated for ten days, not two years or
more, and
emergency help will be a good deal closer than 40 million miles
away. But
their experience will be an important addition to the store of
knowledge
that will make a Mars mission possible. And the Devon Island
teams have to
face a very special threat that will not trouble real Martian
explorers:
polar bears. To compensate, though, Pletser and his colleagues
will have a
unique support system. As they struggle sweating through their
EVAs, an
Inuit hunter will be watching their backs.
Vladimir Pletser hopes to keep a diary of his mission, which
begins on 8
July. His diary updates will be available on this web site from 9
July.
Mars Diary
* En route for "Mars"
http://www.esa.int/export/esaCP/ESAB000VMOC_Life_0.html
Related articles
* Europe goes to Mars -- preparations are well under way
http://www.esa.int/export/esaCP/ESAJXLGBCLC_Life_0.html
* Europe plays a major part in future Mars exploration
http://www.esa.int/export/esaCP/GGG94CBUGEC_Expanding_0.html
* The future of manned spaceflight
http://www.esa.int/export/esaCP/GGGUPPD3KCC_Life_0.html
* Life on Mars?
http://www.esa.int/export/esaCP/GGGJSRD3KCC_Life_0.html
* What we know about Mars
http://www.esa.int/export/esaCP/GGG33G3UGEC_Life_0.html
Related Links
* The Mars Society
http://www.marssociety.org/
* The Haughton impact crater
http://arctic.marssociety.org/images/craterBig.jpg
IMAGE CAPTIONS:
[Image 1:
http://www.esa.int/export/esaCP/ESA0WSZUMOC_index_1.html]
View from Habitat window. Photo: Marc Boucher/SpaceRef.
[Image 2:
http://www.esa.int/export/esaCP/ESA0WSZUMOC_index_1.html#subhead1]
Flashline Mars Arctic Research Station -- April 2001. Photo: MARS
SOCIETY.
[Image 3:
http://www.esa.int/export/esaCP/ESA0WSZUMOC_index_1.html#subhead2]
Vladmir Pletser in Resolute Bay.
==========
(5) NEXT SPACE SCIENCE UPDATE: A STELLAR APOCALYPSE AIDS THE HUNT
FOR LIFE
ON OTHER WORLDS
From NASANews@hq.nasa.gov
Dolores Beasley
Headquarters, Washington,
DC
July 5, 2001
(Phone: 202/358-1753)
William Steigerwald
Goddard Space Flight Center, Greenbelt, MD
(Phone: 301/286-5017)
NOTE TO EDITORS: N01-43
NEXT SPACE SCIENCE UPDATE: A STELLAR APOCALYPSE AIDS THE HUNT FOR
LIFE ON
OTHER WORLDS
What can a dying Sun tell us about the possibility for life on
other worlds?
As a nearby star burns through the last of its fuel and vaporizes
its
surroundings, it is yielding new evidence that planetary systems
around
other stars can support life.
At a Space Science Update, 1 p.m. EDT Wednesday, July 11, in the
James E.
Webb Auditorium at NASA Headquarters, 300 E St. SW, Washington,
DC,
scientists will present observations by the Submillimeter Wave
Astronomy
Satellite (SWAS) that support the search for life on worlds
outside our
solar system.
The panelists will be:
* Dr. Alan Bunner, Science Director, Structure and
Evolution of the
Universe, NASA Headquarters
* Dr. Gary Melnick, SWAS Principal Investigator, senior
astronomer,
Harvard-Smithsonian Center for Astrophysics, Cambridge, MA
* Dr. David Neufeld, professor of physics and astronomy,
Johns Hopkins
University, Baltimore
* Dr. Alan Boss, Department of Terrestrial Magnetism,
Carnegie Institution
of Washington, Washington, DC
* Dr. Karen Meech, astronomer, Institute for Astronomy,
University of
Hawaii, Honolulu
The Update will be carried live on NASA Television. Two-way
question-and-answer capability will be available at participating
NASA
centers. NASA TV is broadcast on GE-2, transponder 9C, C-Band,
located at 85
degrees West longitude. The frequency is 3880.0 MHz. Polarization
is
vertical and audio is monaural at 6.8 MHz. The event will be
webcast live
at: Http://www.nasa.gov
Additional information on SWAS is available at:
http://cfa-www.harvard.edu/cfa/oir/Research/swas.html
===========
(6) ALL FAULT LINES ARE NOT EQUAL
From Andrew Yee <ayee@nova.astro.utoronto.ca>
Pennsylvania State University
Contacts:
A'ndrea Elyse Messer, (814) 865-9481, aem1@psu.edu
Vicki Fong, (814) 865-9481, vfong@psu.edu
June 29, 2001
University Park, Pa -- While most scientists assume that both
sides of a
geologic fault move equal distances during an earthquake, Penn
State
researchers have discovered that not all strike slip faults act
that way.
"In the past, no one looked at the contrast between the two
sides of a
strike slip fault," says Dr. Kevin P. Furlong, professor of
geosciences.
"These faults have always been modeled as if both sides were
equal by
definition."
Furlong; Rocco Malservisi, Ph.D. student in geosciences; and
Timothy H.
Dixon of University of Miami, investigated the Eastern California
Shear
Zone, a strike slip fault system running parallel to the San
Andreas fault
about 150 miles east of San Francisco. The area, on the
Nevada/California
border, is the eastern edge of the interface of the Pacific and
North
American plate boundaries and is linked to the San Andreas fault.
In a
strike slip fault, the ground on each side of the fault moves
along the
fault line, but in opposite directions.
The western side of the fault, consisting of the Sierra Nevada
Mountains,
and the eastern side of the fault, that of the Basin and Range,
have very
different heat flow properties, which the researchers believe is
the cause
of the contrast between the two sides.
"The Sierra Nevada to Basin and Range is an abrupt
transition, thermally and
mechanically," says Furlong.
The heat flow on the Sierra Nevada side is much lower than on the
Basin and
Range side, making the Sierra Nevada side colder as well. These
temperature
differences can be dramatic.
At 12 miles beneath the surface, the temperature on the Sierra
Nevada side
is 375 degrees Fahrenheit, while the Basin and Range side is 1112
degrees
Fahrenheit. According to the researchers, the colder Sierra
Nevada side acts
like a solid block, recovering fairly quickly from an earthquake,
while the
warmer, more viscous Basin and Range side deforms more like
rubber. When an
earthquake occurs, the Sierra Nevada side only needs to snap back
a small
distance, while the Basin and Range side rebounds much more and
then
continues to recover for a much longer time. In between
earthquakes, the
softer Basin and Range side accumulates strain faster than the
more rigid
Sierra Nevada side.
One reason the Eastern California Shear Zone is a good place to
study an
unevenly deforming fault is that a very large earthquake of
magnitude 8 or
more, occurred in this area in 1872. This Owen's Valley
earthquake is far
enough in the past so that the effects of the actual earthquake
can be well
accounted for, making the differences in movement on each side of
the fault
observable.
Furlong, Malservisi and Dixon report in the July 15 issue of the
journal
Geophysical Research Letters, on their on-site study of this
fault. Using
permanent location markers and Geographic Positioning System
equipment, they
were able to record the difference in movement on each side down
to about 1
millimeter. They found a difference of a fraction of an inch a
year on the
rigid side out of a total movement along the fault of 0.5 inches.
Their
findings provide a more accurate method for modeling this
earthquake data,
one that allows the computer models to better fit the ground
reality in the
Eastern California Shear Zone.
"Before the accuracy of G.P.S. became so good, it was
impossible to do this
kind of research," says Furlong. "We could not have
seen the difference
before."
Beside the accuracy issue, the researchers had another problem.
"We cannot just go to the literature and check out old data
sets because the
assumption was symmetry and, in the past, the data was forced to
fit that
assumption," says Furlong.
If the researchers' results hold true, their approach could be
applicable in
many places. While local geography can cloud the existence of
true contrasts
across sides of a fault because of local areas of hard rocks,
gravels or
sands, there are hints of this asymmetry occurring in other
places.
Satellite images of a 1997 earthquake in Tibet show that the
earthquake
occurred more on one side of the fault than the other. The area
is so remote, however,
that it is not currently possible to determine if subsurface
differences are
the cause. Near Papua-New Guinea in the Bismark Sea, measurements
of islands
using G.P.S. are showing asymmetric patterns as well. Furlong and
Malservisi
caution that these are only hints that this phenomenon occurs in
other
places and that nothing has been proven.
The National Science Foundation has funded the researchers to
continue their
work and obtain additional G.P.S. data for the Eastern California
Shear
Zone.
***aem***
EDITORS: Mr. Malservisi is at (814) 863-9902 or at rocco@geodyn.psu.edu by
e-mail; Dr. Furlong is at (814) 863-0567 or at kevin@geosc.psu.edu by
e-mail.
===========
(7) RESEARCHERS PROPOSE NEW GEOLOGICAL FORMATION THEORY
From Andrew Yee <ayee@nova.astro.utoronto.ca>
University of Hawai'i
University Relations
Media & Publications
Honolulu, HI 96822
Telephone: (808) 956-8856
Facsimile: (808) 956-3441
E-Mail: ur@hawaii.edu
Contact:
Shawn Nakamoto, (808)-956-9095
University and Community Relations
For Immediate Release: June 27, 2001
UH Researchers Propose New Geological Formation Theory
HONOLULU -- Throughout geologic history, continents have been
pulled apart
by tectonic forces forming rifts that eventually become new ocean
basins.
Sometimes during this process rock layers near the earth's
surface are
pulled apart and rocks from depths of 35 kilometers or more are
exposed at
the Earth's surface. These deep "crustal" rocks are
usually metamorphic
rocks that have been re-crystallized by heat and pressure.
Surface exposure
often forms domes called metamorphic core complexes, which are
higher than
surrounding terrain.
How these formations develop has been a much-debated question in
geology.
University of Hawai'i researchers Fernando Martinez, Andrew M.
Goodliffe,
and Brian Taylor have proposed a new explanation for these
formations by
studying the offshore areas of Papua New Guinea. Their findings
were
published in the June 21 issue of Nature Journal.
Eastern Papua New Guinea is a present-day example of a
continental land-mass
in the early stages of rifting and forming a new ocean basin.
Here the
processes that rift continents and form ocean basins can be
studied directly
in their active stages. The heat flowing from the Earth's
interior can be
used as a measure of the degree of stretching of the upper strong
layer of
the Earth. Where there has been a great deal of stretching, this
upper layer
is thin and the hotter deeper layers are closer to the surface of
the Earth
producing a high flow of heat.
Using sensitive thermal probes, the researchers measured the flow
of heat
from the Earth's interior in the deep sea sediment. Thermal
measurements
were taken between Papua New Guinea and the D'Entrecasteaux
Islands because
these islands are metamorphic core complexes that are rising at
the same
time that the floors of the surrounding basins are deepening. The
thermal
measurements revealed that the basins do not have elevated heat,
but the
islands do.
Examining what is known about the geology of the islands and
surroundings,
the Hawaii researchers formulated their new model for the
formation of the
islands. They discovered that the basin and islands are in a
region that was
once a continuous layer of dense oceanic crust and mantle (the
layer of the
Earth between the crust and the core), the type of material that
is
generally present for the formation of the floors of major ocean
basins.
This dense oceanic layer was thrust over part of Australia 50 to
60 million
years ago. The result was a heavy oceanic layer pressed tightly
over a
lighter continental layer. When the current extension began, the
upper layer
was split and the lower layer was squeezed up and out through the
crack like
toothpaste, which was the formation of the islands.
The flow and thinning of the lower continental layer caused the
upper
oceanic layer of the surrounding basins to sink but not stretch.
The heat
from the thinning lower layer did not have sufficient time to
cross over the
upper layer, except where the hot lower layer was squeezed out at
the
islands.
This superposition of a denser layer over a lighter one is called
a density
inversion, since it goes counter to the general trend observed on
Earth of
density increasing with depth. Nevertheless, these density
inversions have
occurred repeatedly on Earth as a consequence of collisions of
different
terrains due to the ever-moving tectonic plates. In other areas,
the fact
that density decreases with increasing temperature may create
such a density
inversion in the crust even without collisions and thrusting of
heavy layers
over lighter ones.
The processes at work in raising the islands of eastern Papua New
Guinea may
provide a general explanation for the formation of many similar
core
complexes throughout the world.
===============
(8) LIFE IN THE UNIVERSE? IS ANYBODY OUT THERE?
From ESA Media Relations <ContactESA@esa.int>
Paris, 5 July 2001
Press Release
N° 40-2001
Life in the Universe ? Is anybody out there?
The possibility that there is life elsewhere in the Universe has
always
excited the general public. Scientists are equally enthusiastic:
physicists,
biologists, chemists, cosmologists and astronomers all over
Europe are
researching the age-old question: is there other life in the
Universe?
What is our understanding at the beginning of the 21st
century? Is there
any scientific evidence for other forms of life? How can you
define life?
What signs are we looking for? What would the
reaction be if other forms
of life were discovered?
The European Organization for Nuclear Research (CERN), the
European Space
Agency and the European Southern Observatory, in cooperation with
the
European Association for Astronomy Education, have organised a
competition
to find out what young people in Europe think. The European
Molecular
Biology Laboratory and the European Synchrotron Radiation
Facility are also
involved.
This "Life in the Universe" project is being mounted in
collaboration with
the research directorate of the European Commission for the
European Week of
Science and Technology in November this year. Competitions
are already
under way in 23 European countries to find the best
projects from school students aged between 14 and 19. Entries can
be in one
of two categories: scientific or artistic. The projects can
therefore be
essays, newspapers, websites, artworks, poetry or even a
theatrical or
musical performance. Two winning teams (one in each category)
from each
country will be invited to a final event at CERN in Geneva on
8-11 November
to present their projects to an international panel of experts at
a special
event devoting three days to enquiring into the possibility of
other life
forms existing in our Universe. This final event will be
broadcast all over
the world via the Internet.
The home base of the "Life in the Universe" project is
a vibrant website
www.lifeinuniverse.org
where details of the programme can be found. It is
still under development but already has a wealth of information
and links to
the national websites, where all entries are posted.
Is there other life in the Universe? We do not know -
but the search is
on!
To find out what is happening for "Life in the
Universe" in each country
contact the National Steering Committees:
Austria
Mr Christian Gottfried
Theobaldgasse 16/13
A-1060 Wien
Email : christian.gottfried@cern.ch
Bulgaria
Mrs Veselka Radeva
Astronomical Observatory and Planetarium
PO Box 120
Varna
Email : radevi@mail.varna.techno-link.com
Denmark
Ms Anne Værnholt Olesen
Tycho Brahe Planetarium
Gammel Kongevej 10
DK-1610 København V
Email : Anne_O@tycho.dk
Estonia
Kertu Saks
Tallinn Technology and Science Centre Energy
Põhja Blvd 29,
Tallinn 10415
Email : kertu.saks@energia.ee
Finland
Mr Lauri Kervonen
National Board of Education
PL380
Hakaniemenkatu 2
00531 Helsinki
Email : Lauri.kurvonen@oph.fi
France
Mr Bernard Pellequer
Geospace Observatoire d'Aniane,
Institut de Botanique,
163 rue Auguste Broussonnet,
34090 Montpellier
Email : bernard.pellequer@geospace-online.com
Germany
Ms Elisabeth Lahr-Nilles
Max-Planck-Institut für Radioastronomie
Auf dem Hügel 69
53121 Bonn
Email : e.lahr-nilles@gmx.de
Ou elahr@mpifr-bonn.mpg.de
Greece
Mrs Maragarita Metaxa
63, Ethnikis Antistaseos
152 31 Athens
Email : mmetaxa@compulink.gr
Ireland
Mr Kevin Nolan
School of Applied Science,
Institute of Technology, Tallaght
Dublin 24
Email : knolan@seti.it-tallaght.ie
Italy
Mrs Cristina Palici di Suni
Via Giulia di Barolo 3
TORINO
Email : palici@aerre.it
Luxembourg
Mr Fernand Wagner
Laboratoire de Physique,
Lycée de Garçons d'Esch,
Boite postale 195,
L-4002 Esch/Alzette.
Email : fernand.wagner@ci.educ.lu
Netherlands
Mr Gert Schooten
Holtmate 14
8014 HA
Zwolle
Email : gertschooten@wish.net
Poland
Ms Barbara Popielawska
Space Research Center, P.A.N.
ul. Bartycka 18a
PL 00-716 Warszawa
Email : bpop@cbk.waw.pl
Portugal
Mrs Felisbela Martins
ASTRO - Apartado 52503 Amial
4202-301 Porto
Email : Felisbela.Martins@ip.pt
Romania
Magda Stavinschi
Bucharest,
str. Cutitul de Argint 5,
RO-75212
Email : magda@roastro.astro.ro
Slovak Republic
Mr Dalibor Krupa
Slovak Academy of Sciences
Stefanikova 49
SK-814 38 Bratislava
Email : fyzikrup@savba.sk
Spain
Mrs Rosa Maria Ros
Dept. Applied Mathematics IV,
Technical University of Catalonia,
Jordi Girona 1-3, modul C3
Barcelona
Email : ros@mat.upc.es
Sweden
Mr Björn Lingons
Mediecenter Stockholm,
Box 19612,
S-10432 Stockholm
Email : bjlin@avc.edu.stockholm.se
Switzerland
Mr Michael Reichen
Gymnase de Nyon
Route de Divonne 8
Case postale
1260 Nyon 2
Email : michael.reichen@freesurf.ch
United Kingdom
Mr Alan Pickwick
19 Edale Grove, Sale, Cheshire,
M33 4RG
Email : Alan_C_Pickwick@compuserve.com
For further information, please contact :
Helen Wilson
European Space Agency
ESTEC Education Office
Postbus 299
2200 AG Noordwijk
Netherlands
+31 71 565 5518 (tel)
+31 71 565 5590 (fax)
Email : Helen.Wilson@esa.int
============================
* LETTERS TO THE MODERATOR *
============================
(9) MEN ARE FROM MARS, WOMEN ARE FROM VENUS; BUT WHAT ABOUT
MARTIAN
METEORITES?
From S. Fred Singer <singer@sepp.org>
Dear Benny
We seem to have a problem. Perhaps a reader may have a suggestion
for
solving it.
Heinrich Waenke and other cosmochemists have come to the
conclusion that
certain types of meteorites originated from the surface of Mars,
most likely
as the result of a high-velocity impact.
But I find it difficult to visualize a scenario that can impart a
velocity
of the order of 10 km/sec to a rock coming from such an impact
without the
accelerating force exceeding the crushing strength of the rock.
John Michael Williams seems to have demonstrated that a gentle
acceleration
of the rock by a gas cloud is physically impossible.
Neither of us has a good mechanism for getting a rock off
the Martian
surface with the required velocity.
So -- my question to the chemists: Could the "Martian "
meteorites have come
from Deimos? Or must they originate from the Mars surface, in
which case we
may need to find some mechanism for a more sustained and gentle
acceleration.
Best wishes,
Fred
S. Fred Singer, President
Science & Environmental Policy Project
http://www.sepp.org
=============
(10) JULIO FERNANDEZ & THE ORIGIN OF SHORT-PERIOD COMETS
From Javier Licandro <licandro@tng.iac.es>
Dear Dr. Peiser,
In the CCNet 84/2001 delivered on 3 July 2001, in the two texts
about the
discovery of TNO 2001 KX76 (points 1 and 2, from the NOAO Press
Release
01-10), the idea that short-period comets are originated in the
Edegeworth-Kuiper belt is incorrectly attributed to Fernandez and
to Duncan,
Quinn and Tremaine ("... The existence of the Kuiper Belt
was postulated by
J. A. Fernandez and by M. Duncan, T. Quinn, and S. Tremaine in
the 1980s to
explain the origin of short-period comets.").
Fernandez is the first in provide evidences that short-period
comets are
originated on a flat cometary belt in the trans-neptunian region
(Fernandez
1980, MNRAS 192, 481). By means of Monte Carlo simulations he
studied the
diffusion of comets in such a belt due to mutual close
encounters and concluded that such a cometary belt could maintain
the number
of observed short-period comets in a steady state. Eight years
later,
Duncan, Quinn, and Tremain made also a very interesting
contribution, in
particular in the study of alternative diffusion mechanisms
(Quinn et al.
1988, ApJ 328, L69 and later papers), but, as they indicate in
their 1988
paper, the original idea is from Fernandez: "... An
alternative theory
proposes that SP comets originate in a belt of low-inclination
comets just
beyond the orbit of Neptune, between about 35 and 50 AU (e.g.
Fernandez
1980; Fernandez and Ip 1983)..."
It is not my objective to minimize Quinn, Duncan and Tremaine
excelent
contribution, but the attribution of the original idea only to
Julio
Fernandez is, in my opinion, a matter of justice.
Sincerelly yours,
Javier Licandro
Centro Galileo Galilei & Telescopio Nazionale Galileo
P.O. Box 565, 38700, S/C de La Palma, Tenerife, Spain
============
(11) SHOEMAKER-LEVY 9 ANNIVERSARY
From Andy Smith <astrosafe@yahoo.com>
Hello Benny and CCNet,
Next Monday (16 July) we will observe the 7th anniversary of the
start of
our large NEO wake-up call (SL-9/Jupiter) and the exciting and
alarming
display of real extra-terrestrial destructive power. We were
given this
display, by the way, on the 49th anniversary of what we thought
(before
SL-9) was real power..the first demonstration of atomic explosive
energy.
The one-week show, we witnessed, in 1994, made everything we
thought was
great and powerful look like child's play...and it sent us a
message....KALI
is on the way and there is no time to waste.
Our Great Responsibility
Our Generation is the first one in history (well in excess of
4,000
generations) with a full awareness of the asteroid/comet danger
and the
capability to find the threatening NEOs and to intercept and
deflect them.
That awareness (and capability) places a tremendous
responsibility on our
shoulders....and all who share the knowledge, also share the
responsibility.
We must overcome our differences and primative instincts enough,
now, to
come together, as a global team and to meet this challenge...the
greatest
technical challenge in history.
We always pay tribute to Gene Shoemaker, as a scientist, a person
and as a
leader.... and to the dedicated SL-9 team, on the 16th, and we
strengthen our dedication to do all
we can to help to bring about the level of preparedness we need.
We also
salute our brothers and sisters, in the many countries around the
world, who
share this concern and are working to reach that goal. We value
highly the
CCNet, as our link to this important global family.
We ask you to join us, on the 16th, in a moment of silent
reflection and
renewal and rededication. We will also play Beethoven's First
Symphony
(played by the team on the night of the discovery) and review the
impact
videos.
We Need the Large Telescopes
Because most of the dangerous NEO are smaller than magnitude 21,
it is
important to get large telescopes (5 meters plus) to join in the
hunt, as soon as possible. We are
contacting some of them and their sponsors and we are getting
some
encouraging responses. Some have already been doing productive
work and we
are urging them to make reports to the MPC.
The JPL NEO page contains some very interesting news from the
Sloan Digital
Sky Survey (SDSS) and we are expressing our appreciation to the
staff, the
cooperating institutions, the Sloan family and others, for this
interest in
asteroids and for the research activity. We are also asking the
global
asteroid astronomy community to expand the scope of their present
NEO survey
to include the 98% of the threat population that is smaller than
a
kilometer. There have been some very impressive smaller
discoveries in the
last two months.
NEAT Team Web Data Enrichment
The NEAT team is providing some great NEO data on their new web
pages. See
what you think of the data for the month of JUNE, 2001
(http://neat.jpl.nasa.gov/2001jun.htm).
Outstanding! We hope that kind of
detail will be provided by all of the major teams. Also, we
commend NEOdys
and the MPC for their continuing high-quality data
compilations/presentations.
First-Generation Interception/Deflection
Zenit and Delta based first-generation NEO protective systems
continue to be
the most promising and our effort is aimed at encouraging major
reductions
in the emergency response times (from years down to months). We
are also
hoping we can get SEA LAUNCH to develop an asteroid emergency
contingency
plan. The Deep-Impact Program is an excellent next step toward
readiness and
we commend all who are involved.
Natural Hazards Caucus (NHC)
This important new group, in the U.S. Senate, should be urged to
include
asteroids and comets on the list of major natural threats. We
invite CCNet
members to contact them and their Working Group and to support
this
addition.
UK Update
We also want to request a CCNet update, from the UK team. Are
there any
encouraging developments? Perhaps we can facilitate a contact
between the
U.S. NHC and those in the Parliament who share our concerns.
Happy SL-9/Jupiter 7
========
(12) QUESTIONS ABOUT CELESTIAL OBJECTS COLLIDING WITH THE EARTH
From John Garner <backscatt@worldnet.att.net>
Dr. Peiser,
When I was doing my undergraduate work in Physics I took a basic
Geology
class that I enjoyed immensely. I became interested in a meteor
strike field
around the area of Charleston South Carolina in the U.S.
Also, in the Atlantic floor off the coast of Bimini are two deep
sea holes.
Is it possible that there was an asteroid or comet strike there
within the
last 12,000 years or so? We know the South Carolina meteor field
is there
but could the deep sea holes in the Atlantic ocean floor be a
result of a
meteor or perhaps asteroid that broke into pieces as it
experienced
atmospheric frictional heating?
I would suppose that not every celestial object that strikes the
Earth
leaves an iridium deposit such as the one discovered by Dr.
Alvarez that
occured at the end of the cretacious period, since the Arizona
Meterorite
Crater 50,000 years ago apparently left no such deposit.
I realize that at the end of the last ice age was about the time
several
species of animals went instinct both in America and Siberia. In
fact,
apparently the climate change came so quickly as to facilitate
the freezing
of mammoth carcasses before they could significantly decompose in
Siberia.
Mammoths in North America went extinct and many hold that they
were hunted
to extinction by early North American man, however, the
extinction of the
Sabre Toothed Tiger and several other species of less notoriety
also went
extinct around that same time enjoy no such explaination.
Could the Carolina Meteorite field and deep see holes in the
Atlantic Ocean
possibly have something to do with this?
Thank you for your time, Sir.
Sincerely,
John Garner
==========
(13) AND FINALLY: ON THE ROCKS
From Andrew Yee [ mailto:ayee@nova.astro.utoronto.ca
]
[ http://www.guardianunlimited.co.uk/science/story/0,3605,516748,00.html
]
Thursday, July 5, 2001
On the rocks
Lunar landings can only be fact, not fiction, says Matthew Genge
By Matthew Genge
It was the 1957, Elvis had released Jailhouse Rock, Alec Guiness
appeared on
the silver screen in a film about a bridge and the USSR had just
shocked the
world by launching the first satellite Sputnik. With its eerie
beeping,
Sputnik announced the arrival of the space age and turned the
cold war from
a brooding silent conflict into a race to reach the Moon.
The winner would prove not only their technological superiority
but also
demonstrate the essential virtue of their basic ideology.
However, even with
such high stakes would any nation dare go as far as faking
landings on the
Moon? In a recent survey, 25% of Americans said they believed
that NASA did
just that and humans had yet to walk upon the surface of our
nearest
neighbour in space. But why do so many people believe such an
absurd notion
and is there any real evidence to back it up? Surprisingly there
is.
Perhaps the most persuasive evidence that the Apollo missions
were faked
comes from inconsistencies in the photographs and films taken on
the Moon.
Shadows in many of the pictures are cast not in straight parallel
lines as
from the Sun but as if they were from a nearby floodlight. NASA
would say
that perspective and an uneven land surface have the same effect
but then
they would say that wouldn't they?
Then there are the crosses that were etched on the lenses of the
Apollo
cameras. These should always be on top of the objects in the
pictures.
However, sometimes they're not, suggesting that the images were
added later.
Is this evidence that the pictures were faked? Possibly, but it
could also
be that the bright objects are over-exposed, such as in flash
photography,
and the crosses have been bleached out.
How about the identical hills in photographs taken on supposedly
different
parts of the Moon? Surely this is evidence that the same set was
used to
fake the images? The spokesperson for NASA would no doubt shrug
and say that
one bit of the Moon looks very much like another and perhaps
they'd be
right.
The list of Apollo inconsistencies goes on and on and it would
perhaps be
unfair to dismiss the observant souls who have noticed them as
crackpots. As
with most conspiracy theories, it's just a case of who you want
to believe.
So is there any irrefutable evidence that the Apollo missions
really took
place, that the most momentous landmark event in human history
actually
happened and that we haven't all been taken for one huge PR ride?
Luckily
the answer is in the rocks.
The Apollo missions returned 382 kilograms of rock and there is
one thing
that is absolutely clear, they are not from Earth. The oldest
Apollo rocks,
for example, are 4.44B years old and thus formed some 640M years
before the
oldest rocks found on Earth. The great age of the lunar rocks is
because the
Moon, unlike our planet, is geologically dead and thus its rocks
have not
been disrupted by the churning of its interior and its volcanoes
are long
ago extinct.
The Apollo rocks also lay testament to a very fiery birth that
boiled away
most of the Moon's lighter elements. This revelation led directly
to the
realisation that our Moon formed from the hot debris of a giant
impact with
the Earth only 50M years after our planet itself formed. There
are no rocks
on Earth that tell such a story.
There would be no way to fake these rocks. Stuffing the right
elements into
minerals so they appear to be ancient simply can't be done. It's
a case of
the round hole and the square peg. Only if the peg starts off
round and
through billions of years of radioactive decay ends up square, by
turning
itself into another element, can it make it into the mineral.
Perhaps then the Apollo samples really aren't Earth rocks at all
but some
rare meteorite cleverly adopted by NASA? However, the oxygen they
contain is
very different from known meteorites (except those from the Moon)
and
similar to that of the Earth. Only if the Apollo rocks come from
an object
that formed at a similar distance from the Earth as the early Sun
could this
be explained. The Moon is, of course, the prime candidate.
Conspiracy theories are unfortunately such attractive notions to
the human
psyche that scientific evidence, however elegant, often fails to
impress.
There is, however, one final piece of evidence. Although they
never put a
cosmonaut on the Moon, the Soviets landed the Luna probes which
returned 100
grams of lunar soil. They are identical to the Apollo samples.
Case
dismissed.
[Dr Matthew Genge is a meteorite scientist at the Natural History
Museum
where an Apollo Moon rock can be seen on exhibition.]
© Guardian Newspapers Limited 2001
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