PLEASE NOTE:
*
CCNet 120/2002 - 14 October 2002
-------------------------------
"The seismic station of Irkutsk as well as other seismic
stations of
the region did not record the fall. (The Bodaibo station recorded
a
signal which cannot be easily interpreted). It means, that the
Bodaibo
impact is much weaker than the Tunguska event of 1908 because the
Tunguska
collision was recorded by the Irkutsk station. Note that the
seismic
equipment in 1908 was much worse and the sites are located
approximately at
the same distance from Irkutsk. The negative seismic data
suggests also
that a significant crater was not formed by the Bodaibo
fireball."
--Michael Nazarov, Laboratory of Meteoritics, Moscow, 10
October
(1) U.S. SATELLITES SEE RUSSIAN IMPACT
NEO Information Centre, 13 October 2002
(2) UPDATE ON BODAIBO IMPACT
Michael Nazarov <Nazarov@geokhi.ru>
(3) AN ATMOSPHERIC IMPACT IN THE ORDER OF ~100 TONNES OF TNT
Duncan Steel <D.I.Steel@salford.ac.uk>
(4) NASA RESEARCHERS PROBE METEORITE
Ron Baalke <baalke@jpl.nasa.gov>
(5) MUSES-C LAUNCH PUT OFF
Andrew Yee <ayee@nova.astro.utoronto.ca>
(6) PUNCTUATED EQUILIBRIA IN THE EVOLUTION OF THE LEONID DUST
TRAIL
Marco Langbroek <marco.langbroek@wanadoo.nl>
(7) AND FINALLY: IG NOBELS GO TO DOGS, HONOURING CANINE
TANSLATORS,
CAT-WASHING MACHINES
Andrew Yee <ayee@nova.astro.utoronto.ca>
=============
(1) U.S. SATELLITES SEE RUSSIAN IMPACT
>From NEO Information Centre, 13 October 2002
http://www.nearearthobjects.co.uk/news_display.cfm?code=news_intro&itemID=127
The U.S. Department of Defense have released information obtained
by U.S.
satellites on the fireball event that occurred over Siberia on
Sept 24.
Eye-witness accounts of the event reported a large luminous
object falling
to Earth near Bodiabo in Siberia. Hunters in the region have also
reported
the existence of a crater surrounded by burnt forest suggesting
that an
impact event had occurred. The event was detected by near-by
geophones as a
moderate-earthquake.
U.S. satellites initially detected the fireball at 57.91N and
112.90 E at an
altitude of 62 km and it was tracked to 58.21 N and 113.46 E at
an altitude
of 30 km. The satellite measurements indicate that the total
energy radiated
from the fireball was roughly the equivalent of 0.2 kilotonnes of
TNT.
Although the amount of energy of a meteoroid that is converted
into heat and
light as it falls through the atmosphere is not simply related to
the size
of the meteoroid it can be used to estimate the size of the
event. The
fireball seen over Alaska on January 18, 2000, for example, was
likewise
observed by U.S. satellites and released an energy of around 0.26
kilotonnes. This event, like the Siberian fireball, was detected
by
earthquake geophones and resulted in the fall of the Tagish lake
meteorite.
Only around 1 kg of Tagish lake was recovered from the frozen
surface of a
lake, most of this fragile meteoroid was probably destroyed
during
atmospheric entry. If the Siberian meteoroid, however, consisted
of tougher
materials such as iron then more mass may have survived to
collide with the
ground. Weak meteoroids also lose more of their energy during
flight through
the atmosphere because of their break-up.
The Sikhote Alin meteorite fell in Russia in 1947 and more than
around 70
tons of this meteorite were recovered, many from steep sided
impact pits in
soft soil. Estimates of the energy released by Sikhote Alin vary,
however,
its is likely to have been up to 10-20 kt with most of this
energy lost
during fall through the atmosphere. The event in Siberia on Sept
24 is
unlikely to have been as significant as Tunguska or the event
that generated
meteor crater in Arizona since both of these liberated tens of
megatonnes of
energy. It may, however, prove to have resulted in the fall of an
iron
meteorite although the fact that the fireball was tracked to an
altitude of
30 km, where most fireballs associated with meteorites end,
suggests it is
perhaps not likely to be as large as the Sikhote Alin fall. Only
once
scientists have located and examined the impact site, however,
will the size
of the event be known for certain.
MORE INFORMATION at
http://phobos.astro.uwo.ca/~pbrown/usaf/dod201.txt
=============
(2) UPDATE ON BODAIBO IMPACT
>From Michael Nazarov <Nazarov@geokhi.ru>
Unfortunately, at present we do not know exactly what happen
there. We know
that:
(1) The fall took place near Bodaibo, Irkutsk region on Sept.25
at 1:50 am
of local time
(2) The seismic station of Irkutsk as well as other seismic
stations of the
region did not record the fall. (The Bodaibo station recorded a
signal which
cannot be easily interpreted). It means, that the Bodaibo impact
is much
weaker than the Tunguska event of 1908 because the Tunguska
collision was
recorded by the Irkutsk station. Note that the seismic equipment
in 1908 was
much worse and the sites are located approximately at the same
distance from
Irkutsk. The negative seismic data suggests also that a
significant crater
was not formed by the Bodaibo fireball.
Other information should be checked. Irkutsk scientists think
that the site
of the fall is unknown. They did not tell us about a hunter who
saw a
crater. It would be important to go to Bodaibo and to talk with
eyewitnesses. However I think it will not be easy to find the
site of the
fall. Note the fall took place in night. Therefore, normal people
was
sleeping. If even there are 100 eyewitnesses, a few of them will
tell
something useful about the trajectory of the fireball. Others
will tell
about the sounds and the flash but it is not very important. Note
also, that
a fireball is very impressive and eyewitnesses who
naturally have never
seen it before will exaggerate systematically its power.
Interestingly, in
30-50 years after the Pervomaisky (in 1933) and the Boguslavka
(in 1916)
meteorite falls we got letters from some eyewitnesses who
described their
impressions. Note also that Bodaibo is in a taiga area. There are
not so
many villages there. It makes up additional difficulties to
predict the site
of the fall and to find the meteorite.
The experience of meteorite research in Russia shows three
possible cases:
(1) A meteorite will have never been found in spite of a huge
fireball. This
is the most common case. For last 10-15 years I remember two
observations of
huge fireballs in the Moscow region. In one case we constrained
well the
possible site of the fall but nothing was found in spite of
numerous
attempts. The site was located in a forest.
(2) A meteorite will be found occasionally in a time. The best
example is
the Tsarev fall of 1,200 kg in 1922. It was found in 1968. This
is also a
common case. If even we have some constrains on a site of a fall,
a
constrained area is too big as a rule and a first meteorite
fragment is
recovered occasionally in the area in a time.
(3) A meteorite is found immediately. It occurs if a meteorite
falls in a
vicinity of eyewitnesses or if a fall is really very huge. The
site of the
huge Sikhote Alin fall of 1947 was discovered at the same
day by pilots of
a civil flight. The Bodaibo airport is active. I think that if
there would
be a huge fall in the district, a crater or other destruction in
the taiga
area would be recognized by pilots.
Interestingly that a meteorite named Bodaibo exists already. It
is iron
piece of 15.9 kg found there in 1907.
Sincerely
Dr. Mikhail Nazarov
___________________________________
Laboratory of Meteoritics
Vernadsky Institute of Geochemistry and Analytical Chemistry
Moscow 119991, Kosygin St.,19
phone: 939 7070
fax: 938 2054
e-mail: nazarov@geokhi.ru
============
(3) AN ATMOSPHERIC IMPACT IN THE ORDER OF ~100 TONNES OF TNT
>From Duncan Steel <D.I.Steel@salford.ac.uk>
Hi Benny,
This announcement confirms an *atmospheric* impact as opposed to
a ground
impact.
Peter Brown notes in his release:
>The total radiated energy was 8.6 X 10^11 Joules (6000K black
body).
This figure has a considerable uncertainty due to the requirement
of making
various assumptions about certain input parameters. But if it is
correct to
first order, then it corresponds to an energy equivalent near 100
tonnes of TNT.
Assuming an atmospheric entry speed in the low 20's (km/sec), and
that essentially
all the meteoroid kinetic energy is transformed to radiant energy
(a dubious assumption),
the pre-entry meteoroid mass would then be about 2 tonnes.
A hypervelocity impact on the ground would thus be
contraindicated. A small
fraction of the original meteoroid mass might survive entry
and reach the
ground intact, but it would have done so at the free-fall speed
(i.e. the
same as if it had been dropped from a high-flying
aircraft).
Regards,
Duncan Steel
============
(4) NASA RESEARCHERS PROBE METEORITE
>From Ron Baalke <baalke@jpl.nasa.gov>
NASA News
National Aeronautics and Space Administration
John F. Kennedy Space Center
Kennedy Space Center, Florida 32899
AC 321-867-2468
For Release: Oct. 11, 2002
KSC Contact: Manny Virata
(321) 867-2468
KSC Release No. 99 - 02
MEDIA OPPORTUNITY:
NASA RESEARCHERS PROBE METEORITE
A new NASA study of a one-of-a-kind meteorite found 36 years ago
in
Australia could help provide the science community and industry
with
fundamental knowledge for use in the design of advanced
materials.
Such materials could be used for future spacecraft, improved jet
aircraft
and in various manufactured goods from cars to household
materials. In
addition, the meteorite - now at Kennedy Space Center - could
help reveal
secrets about the core of our planet and its magnetic field.
The 100-pound Mundrabilla meteorite sample, which is on loan to
Marshall
Space Flight Center from the Smithsonian Institution's National
Museum of
Natural History, is being studied by MSFC and KSC, primarily
through the use
of KSC's Computed Tomography Scanner.
Dr. Donald Gillies, discipline scientist for materials science at
MSFC's
Microgravity Science and Applications Department, is the
Principal
Investigator on the study.
"Most meteorites are solid chunks of metal, surrounded by a
rocky surface.
This one is a combination of materials (iron-nickel and
iron-sulfide) that
became solid at different rates in cooling over millions of
years," Dr.
Gillies said. "It offers an amazing opportunity for
understanding
fundamentals of alloy formation."
Pete Engel, an engineering specialist in Wyle Laboratory's
Nondestructive
Testing Laboratory at KSC, has processed the scans of the
meteorite at KSC.
"The CT Scanner is able to reveal the untouched internal
structure of the
meteorite by detecting differences in the densities of its
materials," Engel
said. "Without a tool like the scanner, it would be
impossible to study the
inside of the meteorite without altering it by sawing into it or
grinding it
up."
The idea behind computed tomography - first used in the medical
field - is
to create a picture of a very thin cross section of an object by
passing a
very thin fan of X-rays or gamma rays through it and then
repeating the
process until every slice of an object is imaged in order to
create a 3-D
image. Dr. Gillies and Engel are conducting the meteorite CT work
at KSC
using gamma rays given off by a pencil lead-sized piece of
radioactive
cobalt as it decays.
"This meteorite, like all meteorites, was formed in a lower
gravity
environment than here on Earth," Dr. Gillies pointed out.
"Like experiments
performed on the Space Shuttle or the International Space
Station, this
research allows us to look at fundamental science questions.
Unlike our own
flight experiments, this one represents a billion year
solidification
experiment in low gravity."
NOTE: Media members who wish to view the meteorite and
Computed Tomography
Scanner and interview Pete Engel should call Manny Virata at
867-2468 to
schedule a time from 9 a.m. to 3 p.m. on Wednesday, Oct. 16, for
a tour of
the Nondestructive Testing Laboratory.
==============
(5) MUSES-C LAUNCH PUT OFF
>From Andrew Yee <ayee@nova.astro.utoronto.ca>
Institute of Space and Astronautical Science
Sagamihara City, Japan
26 September 2002
MUSES-C Launch Put Off
The MUSES-C ISAS asteroid mission which was scheduled to be
launched in
coming December, has been put off till the next launch window
(May 2003).
The MUSES-C team found an O-ring of a regulator for attitude
control system
broken during the checking operation. As some other similar
O-rings are used
for MUSES-C, ISAS team has been engaged in detailed investigation
about
related components. As of the present moment, the O-ring in
trouble has been
changed, and the investigataion has already confirmed the whole
attitude
control system has no problem. The process, however, costed a
long time, and
ISAS is obliged to postpone the launch of MUSES-C from scheduled
December
2002 to the next launch window, May 2003.
Thanks to many people's cooperation, the applicants to
"Let's go to our Star
Prince" reached about 880,000. ISAS would like all
applicants to understand
the situation that the launch delay this time also means safer
arrival of
880,000 names at the target asteroid, 1998SF36. In spite of this
launch
delay, arrival times to the asteroid and the earth will not be
changed.
=============
(6) PUNCTUATED EQUILIBRIA IN THE EVOLUTION OF THE LEONID DUST
TRAIL
>From Marco Langbroek <marco.langbroek@wanadoo.nl>
For those interested, I now have a pdf (100 Kb) reprint of the
paper below
available. Send me a note in case you are interested.
Cheers,
Marco Langbroek
- - - -
Monthly Notices of the Royal Astronomical Society
Volume 334 Issue 2 Page L16-L20 - August 2002
doi: 10.1046/ j.1365-8711.2002.05679.x
Title: Observational evidence for punctuated equilibria in the
evolution of
Leonid dust trail widths and implications for meteor rate
predictions
Author: Marco Langbroek
Abstract - Meteor activity profiles are reported for the three
Leonid storms
of 1999 and 2001 and the substorm of 2000. These yield
information on the
evolution of the shape of cross-sections through Leonid dust
trails of known
age. Leonid dust trails shed 4 or more revolutions of the parent
comet ago,
widen rather sudden, compared to the 3 revolutions old dust trail
encountered in 1999. Trails shed 4 respectively 7 revolutions ago
differ
little from each other in width by contrast. It is proposed that
the
evolution of Leonid dust trail widths is not gradual with age but
progresses
by a process of punctuated equilibria, parallel to a similar
pattern in the
orbital evolution of the parent comet 55P/Tempel-Tuttle. Trails
shed 4 to 7
revolutions ago appear to represent an equilibrium phase. The
current series
of encounters with these trails therefore yield a unique
opportunity to
investigate the spatial dust density distribution for trails in
this age
range. Minimum and maximum rate estimates are given for the
upcoming 2002
Leonids. The minimum rates possible amount to zenith hourly rates
of 3000
for the 4-revolution trail encounter and 2500 for the
7-revolution trail
encounter. Maximum rates possible, but unlikely to be fulfilled,
are 6500
for the 4-revolution trail and 7100 for the 7-revolution trail.
We can look
forward with confidence to two new Leonid storms in 2002 with
rates at least
equal to and perhaps above those of 2001.
- - - -
Marco
Langbroek
e-mail: marco.langbroek@wanadoo.nl
Diefsteeg 1
NL-2311 TS Leiden
the Netherlands
http://home.wanadoo.nl/marco.langbroek/
====================
(7) AND FINALLY: IG NOBELS GO TO DOGS, HONOURING CANINE
TANSLATORS,
CAT-WASHING MACHINES
>From Andrew Yee <ayee@nova.astro.utoronto.ca>
Office of News and Public Affairs
Harvard University
Cambridge, Massachusetts
October 10, 2002
Ig Nobels go to the dogs, honoring canine translators,
cat-washing machines:
Annual awards mix science with circus as the theme of the year is
'jargon'
By Beth Potier, Harvard Gazette Staff
beth_potier@harvard.edu
Staff photos by Ruby Arguilla
Ostrich lust, belly button lint, and creative corporate
accounting took
honors at the Twelfth 1st Annual Ig Nobel
[ http://www.improb.com/ig/2002/2002-details.html
] Prize Ceremony in Sanders
Theatre on Oct. 3, an event that celebrates scientific
achievements that
"cannot or should not be reproduced."
Prize winners paid their own expenses to travel from four
continents to
collect their prizes -- a certificate and a statuette of
chattering teeth --
and participate in an awards ceremony that was equal parts
science and
circus. Genuine Nobel Laureates Dudley R. Herschbach, Frank B.
Baird Jr.
Professor of Science; Abbott and James Lawrence Professor of
Chemistry
Emeritus William Lipscomb; and New England Biolabs' Richard
Roberts passed
out awards and gamely participated in the irreverence.
As paper airplanes soared and costumed audience members shouted
and cheered,
Ig Nobel winners graciously accepted the awards that made light
of their
legitimate research. The awards and ceremony were
"reluctantly inflicted
upon you," said the evening's program, by the science humor
magazine Annals of Improbable Research (AIR).
Arnd Leike, of the University of Munich, chugged a beaker of beer
after
accepting the physics Ig Nobel for research that demonstrated
that beer
froth obeys the mathematical Law of Exponential Decay.
"I had much fun in taking data and writing this paper,"
said Leike. "Thank
you, and cheers."
Accepting the biology award for a report he co-authored on
"Courtship
Behaviour of Ostriches Towards Humans Under Farming Conditions in
Britain,"
a dapper Charles G. Paxton quipped that "For too long,
science has had its
collective head in the sand over this particular issue."
Ceremony censors nixed a demonstration of the medicine Ig Nobel,
awarded to
University College, London, professor Chris McManus for his
report on
"Scrotal Asymmetry in Man and in Ancient Sculpture."
A team of Japanese scientists accepted the Ig Nobel for peace for
Bow-Lingual, a dog-to-human translation device, and Eduardo
Segura of Spain
won the hygiene award for inventing a washing machine for cats
and dogs.
The literature award went to Vicki Silvers of the University of
Nevada,
Reno, and David Kreiner of Missouri State University for their
paper
exploring "The Effects of Pre-Existing Inappropriate
Highlighting on Reading
Comprehension."
"The moral of the story is, do not buy a textbook that has
been highlighted
by an idiot," said Kreiner. After the ceremony, he admitted
that he and
Silvers were both honored and somewhat miffed that their work was
recognized
with an Ig Nobel. "We took this as serious, and we still
do," he said.
Not surprisingly, none of the winners of the economics prize --
the
executives, directors, and auditors of Enron, WorldCom, Kmart,
Arthur
Andersen, and other battered corporations -- claimed the honors
in person.
They were collectively cited for "adapting the mathematical
concept
of imaginary numbers for use in the business world."
Scientific hijinks and dramatic tomfoolery surrounded the actual
bestowing
of awards. The evening's theme, jargon, was played out in the
world premiere
of the four-act "Jargon Opera." The opera was set at
the International
Jargon Conference where, sang one of the performers, "each
syllable is
billable."
A range of "Ignataries," including National Public
Radio "Science Friday"
host Ira Flatow and Alyssa Goodman, professor of astronomy at the
Harvard-Smithsonian Center for Astrophysics, delivered
"24/7" seminars on
topics ranging from neurobiology to animals. Each lecturer
summarized his or her topic in 24 seconds and then explained it
in lay terms
in seven words.
"Star light, star bright, it's my job," was Goodman's
description of
astrophysics.
Co-sponsored by the Harvard Computer Society, the
Harvard-Radcliffe Science
Fiction Association, and the Harvard-Radcliffe Society of Physics
Students,
the Ig Nobels aspire, remarkably, to a goal higher than hilarity:
The
event's organizers hope that they can spark an interest in
science
through humor.
"It lets scientists have a night when it's OK to have fun in
public," said
AIR editor and master of ceremonies Marc Abrahams, and it lets
the public
see that even Nobel laureates can cut loose.
"Everyone involved wants to tempt a few more people into
getting curious
about science," he added.
[NOTE: Images supporting this article are available at
http://www.hno.harvard.edu/gazette/2002/10.10/14-igs.html
]
--------------------------------------------------------------------
CCNet is a scholarly electronic network. To
subscribe/unsubscribe, please
contact the moderator 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. The fully
indexed archive
of the CCNet, from February 1997 on, can be found at
http://abob.libs.uga.edu/bobk/cccmenu.html.
DISCLAIMER: The opinions,
beliefs and viewpoints expressed in the articles and texts and in
other
CCNet contributions do not necessarily reflect the opinions,
beliefs and
viewpoints of the moderator of this network.
----------------------------------------------------------------------------