PLEASE NOTE:
*
CCNet 12/2001 - 25 January 2001
------------------------------
"For the first time it looks as if a major natural threat to
humans
and other living things could be largely overcome - provided that
we
can first actually discover and plot the orbits of most of the
dangerous asteroids. We can then predict when and where
individual
impacts might occur 10 or even 100 years ahead, in good time to
take
countermeasures."
--Harry Atkinson, Chairman of the UK Task Force on
Near-Earth Objects
"The Labour peer Lord Winston warned last night of an
international
crisis in science, levelling the blame at protesters such as the
fuel
lobby, arts graduates, the press, and even fellow scientists.
[...] Lord
Winston said the growing suspicion of science put Britain's
economic
growth put in jeopardy, and lambasted the press for printing
"absolute
nonsense" on stem cell research. He highlighted "single
issue protest
groups" as a particular threat, accusing such groups of
distorting public
opinion via "manufactured protest". He accused
scientists of being too
reluctant to engage with the media."
Chris Hughes, The Independent, 24 January 2001
(1) INTERVIEW WITH NEO TASK FORCE CHAIRMAN HARRY ATKINSON
SPACE UK, Journal of the British National
Space Centre, January
(2) CATASTOPHES AND HUMAN EVOLUTION: OBSERVATIONS ON THE FUTURE
OF MAN
SpaceDaily, 25 january 2001
(3) SPACE TECHNOLOGY TO ASSIST AGRICULTURAL PLANNING IN INDIA
The Times of India News Service, 25 January
2001
(4) STUDY SUGGESTS VENUS COULD HAVE BEEN A WET PLANET
Andrew Yee <ayee@nova.astro.utoronto.ca>
(5) STUDY SUGGESTS MARS COULD HAVE BEEN A WET PLANET
Andrew Yee <ayee@nova.astro.utoronto.ca>
(6) SCIENTISTS RUSH TO PROPOSE PLUTO MISSION
Irving Robbins <Robbins@postbox.csi.cuny.edu>
(7) VIDEO METEOR OBSERVATIONS 2000
Sirko Molau <molau@informatik.rwth-aachen.de>
(8) METEOROIDS
Duncan Steel <D.I.Steel@salford.ac.uk>
(9) SPIEGEL ARTICLE
Hermann Burchard <burchar@mail.math.okstate.edu>
(10) LISTENING TO SOUNDS FROM AN EXPLODING METEOR
GEOPHYSICAL RESEARCH LETTERS, VOL. 28,
NO . 1, PAGES 41-44, JANUARY 1, 2001
(11) IS JUPITER A PLANET?
Roy Tucker <tucker@noao.edu>
(12) OLBERS' ANSWER
Andrew Ferguson Nimmo <andy-nimmo@ntlworld.com>
(13) AND FINALLY: LABOUR PEER WARNS OF 'CRISIS' IN SCIENCE
The Independent, 24 January 2001
============
(1) INTERVIEW WITH NEO TASK FORCE CHAIRMAN HARRY ATKINSON
From SPACE UK, Journal of the British National Space Centre,
January 2001
http://www.bnsc.gov.uk/resource/publications/space_uk/issue03/03.html
Last January, the Science Minister, Lord Sainsbury, asked a
distinguished
three man team to report back to the British National Space
Centre on the
nature of Near Earth Objects (NEOs) - asteroids or comets that
come close to
the Earth and the potential threat they pose. The Task Force was
also asked
to consider how the United Kingdom could best contribute to
international
research efforts concerning NEOs.
The Task Force was chaired by Dr Harry Atkinson, formerly of the
Science and
Engineering Research Council (SERC) and past Chairman of the
European Space
Agency's Council. He was joined by Sir Crispin Tickell, a
distinguished
diplomat who has played a prominent role in dealing with
environmental issues, and Professor David Williams of University
College
London, a former President of the Royal Astronomical Society.
Their NEO Report was published last year and is available on the
internet at
http://www.nearearthobjects.co.uk
Could you give me a little bit of background? Is this the sort of
area that
you've been involved with before?
No, I've never previously had anything to do with NEOs although
I've been
involved with astronomy since 1972, when I was invited to come
back to SERC
to head Astronomy and Space, after 3 years in the Cabinet Office.
Were you surprised when you were asked to be in this Task Force?
Yes indeed, but I was also rather pleased at the chance of being
involved in
what promised to be a most interesting subject. None of the task
force
members knew much about NEOs - even David Williams, because his
field of
astronomy is very different from this. We all started off being a
bit
sceptical - we wondered whether the threat (from NEOs) should be
taken
really seriously.
As I understand it, you came to the conclusion that it should be?
Absolutely, I soon learnt that asteroids and comets had been
hitting the
Earth ever since it was formed over 4 billion years ago. The ice
in the
comets brought water and the asteroids brought carbon - together
the
building blocks of life on the Earth. These collisions are bound
to
continue. It's not a question of whether we will be hit again,
but when.
Although the probability of a major impact is very small, the
consequences
are extremely large.
You made 14 recommendations. I wonder if you could pick out some
that you
consider to be particularly important?
They're all important, but they can be divided into two types.
First, those
about the telescopes and so on needed to increase our scientific
understanding of the threat, and secondly those concerned with
the
organisation required for the science and for possible actions -
in Britain,
within Europe and internationally.
On the science side, building a 3 metre-class telescope in the
southern
hemisphere with other countries is extremely important, so that
we can learn
more about the risk from small objects, down to 300 metres in
diameter or
even less. The US, mainly through NASA, is at present leading the
world in
the discovery and understanding of near Earth asteroids and
comets. This
followed a request in the 1990s from the US Congress, who take
the matter
seriously.
US astronomers have already discovered about 50% of the estimated
1000 or so
asteroids over 1 km across which could cause catastrophic global
damage. But
300 metre asteroids are much more numerous and can cause great
damage on a
regional scale. If a 300 metre object hit the sea - the most
likely place,
as water covers two-thirds of the Earth's surface - the large
tsunami (tidal
wave) created would have very serious consequences on the
coastlines of
countries many thousands of miles away.
These smaller NEOs are not being surveyed systematically by the
US, so our
proposal, if implemented, would take the understanding of the NEO
risk into
a new realm.
On the organisational side, we recommend that the Government
should discuss
with other governments what should be done on a worldwide basis
about the
threat, which concerns us all. And we recommend that Europe as a
whole
should consider what should be done collectively and in
collaboration with
the United States and other countries.
In our view it's also most important that Britain sets up a
national centre
of expertise for NEOs. This should provide a means of
communicating with the
public in Britain about the risks in a sober, open sort of way.
It would
also advise the Government and help to link with other countries
and
international organisations.
We've also seen that there are things that could be done in the
long term to
divert a potentially dangerous asteroid or comet from hitting the
Earth, and
these things should be studied with other countries. This is not
science
fiction - right now a NASA spacecraft is orbiting an asteroid
(Eros), which
calls on quite a lot of the technology required to deflect an
asteroid.
For the first time it looks as if a major natural threat to
humans and other
living things could be largely overcome - provided that we can
first
actually discover and plot the orbits of most of the dangerous
asteroids. We
can then predict when and where individual impacts might occur 10
or even
100 years ahead, in good time to take countermeasures.
Your recommendations obviously have financial implications. Did
you look at
these at all?
Our task was to advise how Britain should contribute to an
international
effort. We were not asked to look at costs. But when we'd reached
our
conclusions, it was clear that our prime scientific aims could be
achieved
with relatively modest expenditure - largely with ground-based
telescopes,
often by using small amounts of time on existing telescopes, or
using data
gathered for quite different purposes by future ESA space science
missions.
For the 3 metre telescope, a keystone of our science
recommendations, we
propose a partnership with other countries, so the UK would only
have to pay
a fraction of the cost.
But I understand one of the recommendations suggested using
microsatellites
to look at NEOs as well?
Yes, we said that the use of small, relatively cheap
microsatellites should
be seriously considered with other countries. There is no doubt
that this
would bring a new dimension to understanding the nature of
different types
of asteroid and comet, and be important in assessing the risk and
considering how to mitigate it. We also noted that the UK, partly
through a
group at the University of Surrey, has considerable expertise in
this field.
I might add that the UK is generally very well placed to play an
important
role in an international context, not only because of our
scientists and
technologists and the excellent telescopes to which we have
access, but also
through our high tech industry.
What has been the reaction to your report?
It has been received extremely well by the UK media. And the
report has been
well covered by the media on the Continent and in other countries
including
Canada, Australia and New Zealand. The media have taken this
seriously. What
really impressed me was the lack of the so-called "giggle
factor" which the
subject often generated in the past.
Lord Sainsbury has welcomed our approach and has said that he
will give the
government's conclusions by the turn of the year [I understand
that HMG's
response is now expected to be announced in the next couple of
weeks, BJP].
Every indication is that that our recommendations will be taken
seriously,
and I hope for a really positive response.
Dr Harry Atkinson was born in New Zealand. He was attached to the
Cabinet
Office in the early 1970s, on the staff of the Chief Scientific
Adviser,
where his tasks included reviewing all governmental activities in
environmental pollution. Subsequently, in the Science and
Engineering
Research Council his responsibilities included astronomy and
space. This
involved UK co-operation with other countries in many space
science
missions, and in ground-based astronomical facilities in
Australia, South
Africa, Hawaii and La Palma. He helped to set up the European
Synchrotron
Radiation Facility at Grenoble and the six-nation EISCAT radar
facility in
the Arctic Circle. For a number of years until 1999 he was Chief
Scientist
of the British insurance industry's Loss Prevention Council.
Copyright 2001, BNSC
==============
(2) CATASTOPHES AND HUMAN EVOLUTION: OBSERVATIONS ON THE FUTURE
OF MAN
From SpaceDaily, 25 january 2001
http://www.spacedaily.com/news/life-01b1.html
by Worth F. Crouch (Talako)
Hope - January. 25, 2001. The development of space flight and
nuclear
explosive technology seem to verify the argument that there is an
upward
spiral of intellectual evolution on Earth. Although some other
terrestrial
animals exhibit a degree of intelligence only human beings can
build
machines capable of interplanetary flight, and have invented
nuclear
weaponry that can be designed to temporarily protect the Earth
from
catastrophic cosmic bombardments. Moreover, since October 1996
technological
societies have learned how symbiotic life is by utilizing the
enclosed
laboratory Biosphere 2, operated by Columbia University outside
Tucson
Arizona. While living in the Biosphere it was discovered that
humans can not
exist long in an isolated environment without many of Earth's
living
organisms, or for that matter nonliving variable factors to
sustain them in
an ecosystem.
Moreover, in order to avoid extinction from minor cosmic
catastrophes
mankind can use actualized scientific knowledge to protect its'
world by
sending rockets with nuclear warheads to intercept incoming
comets or
asteroids. However, animal and plant populations must eventually
be
dispersed to other planets, or space habitats, that have been
terraformed,
to avoid major cosmic catastrophes that will cause extinction.
FULL ARTICLE at http://www.spacedaily.com/news/life-01b1.html
===============
(3) SPACE TECHNOLOGY TO ASSIST AGRICULTURAL PLANNING IN INDIA
From The Times of India News Service, 25 January 2001
http://www.timesofindia.com/250101/25mban1.htm
Space technology for agriculture soon
BANGALORE: The advantages of applying space technology in
agriculture will
come to the fore when the Agro-Climatic Planning and Information
Bank (APIB)
project will be put into operation during the forthcoming kharif
season in
July in three districts of Bijapur, Tumkur and Shimoga.
APIB is a pilot project taken up by the Regional Remote Sensing
Satellite
Centre (RRSSC) to compile a comprehensive information helpful to
the farmers
in their day-to-day agricultural activities through satellite
mapping.
It includes strength of the soil, quality and quantity of manure
component,
irrigable land, seeds and manure that could be used and the
all-important
climalogical parameters.
Speaking to The Times of India, APIB Project Director P.P.
Nageshwar Rao
said the project undertaken at the instance of the Planning
Commission in
three districts at a cost of Rs 50 lakh was completed last month
and its
operational service will begin in July.
``It took 30 months to complete the project which is the first of
its kind
in the country,'' he added.
According to Rao, the information will help the agriculture
department to
plan its cropping pattern and the quantity of fertiliser required
besides
the likely yield to evolve methodology for its marketing.
``Now that we have a methodology to compile the information, we
need less
than two years to complete the satellite mapping of the entire
state which
will likely to cost Rs 12 crore to Rs 15 crore,'' he added.
According to Rao, the RRSSC adopted remote sensing and global
information
system methods to compile the data while the information
collected manually
from various agencies helped them to compare and come out with a
decision-support system.
``About 70 agricultural officers have been trained to download
the data and
feed it into the web. They will in turn train their subordinate
personnel.
However, RRSSC officers will also be present during the operation
to take
care in case of any eventuality," he added.
Copyright 2001, The Times of India
=================
(4) STUDY SUGGESTS VENUS COULD HAVE BEEN A WET PLANET
From Andrew Yee <ayee@nova.astro.utoronto.ca>
Washington University in St. Louis
St. Louis, Missouri
Contact: Tony Fitzpatrick, tony_fitzpatrick@aismail.wustl.edu,
314-935-5272
FOR IMMEDIATE RELEASE: January 24, 2001
Study suggests Venus could have been wet planet
Researchers at Washington University in St. Louis, studying
hydrous mineral
decomposition rates at extreme temperatures, have concluded that
hot and dry
Venus may have been a wet planet in the past, like Earth and
ancient Mars.
The new evidence suggesting a wetter Venusian history comes from
a series of
experiments documenting the chemical stability of tremolite for
several
billion years at temperatures similar to that of Venus' surface,
about 740
Kelvin or roughly 870 degrees Fahrenheit (F).
Tremolite is a mineral that forms in the presence of water. If
tremolite or
some other hydrous mineral can be detected on the surface of
Venus, then it
can be concluded that Earth's once-wet neighbor lost its water
over time,
putting to rest an enduring question in planetary science.
Graduate student Natasha M. Johnson and Professor Bruce Fegley,
Jr., Ph.D.,
of the Planetary Chemistry Laboratory in Earth and Planetary
Sciences at
Washington University, reported their findings in the paper
"Water on Venus:
New Insights from Tremolite Decomposition," Icarus, 146, pp.
301-306, July,
2000.
"Ours is the first study that investigates hydrous mineral
decomposition
rates with applications to Venus," says Johnson. "We
have shown that
tremolite can withstand extreme temperatures and remain intact
for billions
of years. If we can go to Venus and find tremolite, or some other
hydrous
mineral, then we would have proof that Venus had water in its
past."
Indirect evidence that Venus had water in the past is found in
its high
deuterium/hydrogen (D/H) ratios. If the high D/H ratios are the
result of
lighter hydrogen (deuterium is a heavier form of hydrogen)
escaping Venus'
atmosphere to space, then it is possible that Venus had water in
the past.
But the D/H ratio of Venus varies relative to that of Earth, and
comets and
meteorites can also have high D/H ratios, so other types of
evidence of
water are needed.
Johnson and Fegley's research on the decomposition rate of
tremolite shows
that the evidence is in the rocks. "We want to know if it is
worth our time
to go to Venus and look for minerals that have water in
them," says Johnson.
"When you go backpacking, you want to know where you are
going and what you
need to carry. These experiments are laying the foundation, and
saying,
"Hey, should we, or should we not, bring a parka?"
Should we be looking for
hydrous minerals on Venus or is it a waste of time?"
Johnson and Fegley conducted over 200 experiments, heating
samples of
tremolite in laboratory furnaces at temperatures of up to 1240
Kelvin (about
1770 degrees Fahrenheit) for as long as 20 months, periodically
weighing
them to document the amount and rate of decomposition.
Tremolite, an amphibole, and other hydrous minerals contain OH
(hydroxyl
groups as part of a lattice holding these minerals together.
Amphiboles are
formed when lava and magma interact with water. In the case of
tremolite, it
is a metamorphic mineral generally found in dolomitic-type
limestone.
Amphiboles are thermodynamically unstable and according to theory
should
decompose rather quickly at high temperatures.
But Johnson and Fegley's experiments indicate that tremolite is
much more
stable than previously thought, and would take about 4 billion
years to
decompose by half in conditions similar to Venus' surface.
"Diamonds are a
good analogy for what is happening with tremolite," says
Johnson. "Diamonds
are unstable at the surface of the Earth; graphite is the stable
form. But
you don't see diamonds popping into little chunks of graphite on
people's
fingers."
If tremolite and other amphiboles formed on Venus at some time in
the past,
they should be detectable using infrared reflectance spectroscopy
and other
current technology.
The researchers also are measuring decomposition properties of
other hydrous
minerals. Surprisingly little is known about these minerals with
the
exception of those with commercial purposes like asbestos and
other
insulators. "This research could give us some idea about the
formation of
our solar system, and has applications on Earth for investigating
metamorphic regimes or subduction zones," says Johnson.
================
(5) STUDY SUGGESTS MARS COULD HAVE BEEN A WET PLANET
From Andrew Yee <ayee@nova.astro.utoronto.ca>
News Office
Massachusetts Institute of Technology
Cambridge, Massachusetts
CONTACT:
Deborah Halber, MIT News Office
(617) 258-9276, dhalber@mit.edu
JANUARY 24, 2001
Mars magmas once contained a lot of water,
researchers from MIT and U. of
Tennessee report
Finding suggests that volcanos helped bring water to the planet's
surface
millions of years ago
CAMBRIDGE, Mass. -- Evidence from a Martian volcanic rock
indicates that
Mars magmas contained significant amounts of water before
eruption on the
planet's surface, researchers from the Massachusetts Institute of
Technology, the University of Tennessee and other institutions
report in the
Jan. 25 issue of Nature.
Scientists say that channels on Mars's surface may have been
carved by
flowing water and an ancient ocean may have existed there, but
little is
known about the source of the water. One possible source is
volcanic
degassing, in which water vapor is produced by magma spewing from
volcanos,
but the Martian rocks that have reached Earth as meteorites have
notoriously
low water content.
This study shows that before the molten rock that crystallized to
form
Martian meteorites was erupted on the surface of the planet, it
contained as
much as 2 percent dissolved water.
When magma reaches the planet's surface, the solubility of water
in the
molten liquid decreases and the water forms vapor bubbles and
escapes as
gas. The process is similar to the release of gas bubbles that
occurs when
you open a can of soda.
Although this doesn't explain how water got into Mars in the
first place, it
does show that water on the red planet once cycled through the
deep interior
as well as existed on the surface, as similar processes have
cycled water
through the Earth's interior throughout geologic history.
A VISITOR FROM MARS
Timothy L. Grove, professor of Earth, Atmospheric and Planetary
Sciences at
MIT, and University of Tennessee geologist Harry Y. McSween Jr.
analyzed the
Mars meteorite Shergotty to provide an estimate of the water that
was
present in Mars magmas prior to their eruption on the surface.
Shergotty, a meteorite weighing around 5 kilograms was discovered
in India
in 1865. It is one of a handful of proven Mars meteorites that
landed on
Earth. It is relatively young -- around 175 million years old --
and may
have originated in the volcanic Tharsis region of the red planet.
Its measured water content is only around 130-350 parts per
million. But by
exploring the amount of water that would be necessary for its
pyroxenes --
its earliest crystallizing minerals -- to form, the researchers
have
determined that at one time, Shergotty magma contained around 2
percent
water. They also have detected the presence of elements that
indicate the
growth of the pyroxenes at high water contents.
This has important implications for the origin of the water that
was present
on the surface of the planet during the past. This new
information points to
erupting volcanos as a possible mechanism for getting water to
Mars's
surface.
SQUEEZING HYDROGEN INTO ROCKS
In the interior of Mars, hot magma is generated at great depth.
It then
ascends into the shallower, colder outer portions of the Martian
interior,
where it encounters cooler rock that contains hydrogen-bearing
minerals.
These minerals decompose when heated by the magma and the
hydrogen is
released and dissolves in the magma.
The magma continues its ascent to the surface of the planet. When
it reaches
very shallow, near-surface conditions in the crust, the magma
erupts and its
water is released in the form of vapor.
The magma holds the water-creating hydrogen as the rock
circulates
underneath the crust. It undergoes changes as it moves from areas
of
enormous heat and pressure to cooler areas nearer the surface.
When it
finally erupts through a volcano, the magma releases its water in
the form
of vapor.
Grove recreates Mars and moon rocks in his laboratory for these
studies. By
subjecting synthetic rocks to conditions of high temperature and
pressure,
he can tell how much water was contained in magma at the time
that its
crystals were formed. "What my experiment can do is estimate
how much water
was involved in the process that led to the formation of Mars
meteorites.
The only way you can reproduce the unique chemical composition of
these
minerals is to have water present," he said.
Other authors on the Nature paper include McSween's graduate
student, Rachel
C. F. Lentz; Lee R. Riciputi of the chemical and analytical
sciences
division of Oak Ridge National Laboratory; Jeffrey G. Ryan, a
geologist at
the University of South Florida; and Jesse C. Dann and Astrid H.
Holzheid of
MIT's Department of Earth, Atmospheric and Planetary Sciences.
This work was partly supported by NASA.
==============
(6) SCIENTISTS RUSH TO PROPOSE PLUTO MISSION
From Irving Robbins <Robbins@postbox.csi.cuny.edu>
DPS PRESS RELEASE - January 24, 2001
SCIENTISTS RUSH TO PROPOSE PLUTO MISSION
On December 20, 2000, NASA announced that it would be soliciting
proposals
for a mission to the Pluto-Charon system and the Kuiper Belt
beyond to
arrive at Pluto by 2015. The formal announcement of opportunity
was released
January 19, 2001. Proposals are due on March 21, 2001.
Although this is not
a guarantee that NASA will fly this mission, the Division for
Planetary
Science (DPS) of the American Astronomical Society applauds
NASA's
initiative in opening the
process of developing a Pluto mission to the innovative ideas of
the
Planetary Science community and allowing open competition to help
ensure a
cost effective solution for this mission rather than to cancel
it. The
extreme tilt of Pluto's rotational axis is causing more of its
surface to be
in constant darkness as its orbit carries it further away from
the Sun. Its
very thin atmosphere will at some point freeze out, precluding
its study. Optimal
conditions for studying Pluto and its moon Charon in situ will
not return
for 200 years. In its press release of November 16, the executive
Committee
of the DPS called for increased competition and external peer
review for all
missions as a proven mechanism for seeking the most performance
and return
at reasonable cost. While this will be a very challenging mission
to develop
on a short schedule, it will be our best chance for centuries to
visit and
study the last unexplored planet in our solar system.
Contact: Dr. Mark V. Sykes
DPS Chair
520-621-5381
sykes@as.arizona.edu
=============
(7) VIDEO METEOR OBSERVATIONS 2000
From Sirko Molau <molau@informatik.rwth-aachen.de>
AKM Video Meteor Observations 2000 - Summary
============================================
The last year was a very successful one for the video observers
in the
German Arbeitskreis Meteore. 8 (1999: 5) observers recorded in
239 (1999:
120) nights and 2301.3 hours (1999: 1002.4) effective observing
time an
overall of 11,659 (1999: 6,476) meteors. In other words: The
outcome of last
year could be doubled. 239 observing nights is a coverage of
almost 2/3 of
the year!
There are three camera stations (Aachen, Dresden, Marquardt)
which supplied
observations in all twelve months. The other stations were only
part-time
operated. About 1/3 of the observing time was supplied by Juergen
Rendtel
and Sirko Molau, the last third was contributed by the remaining
observers.
Ulrich Sperberg had to give up already in January when his image
intensifier
broke down. As soon as the new AKM video cameras will be ready,
his station
Salzwedel will become active again. Because of poor camera
parameters, the
video system of Detlef Koschny recorded only very few meteors in
the first
months. In August, however, it got a new fast wide-angle lens and
yielded
similar detection rates as the other cameras from then on.
Table 1 gives the detailed statistics of operation times for all
participating video observers. RENJU and MOLSI operated their
systems in
virtually every clear night, even if skies cleared only briefly.
Hence, the
different number of observing nights reflects better weather
conditions
especially in the cold months in east Germany. On the other hand,
the image
intensifier of AVIS is more powerful than that of CARMEN,
resulting in a
better limiting magnitude and more meteor records. Whereas CARMEN
detected
an average of 3.8 meteors per hour, it was 6.3 meteors per hour
for AVIS.
Table 1: Operation Times of the AKM Video Cameras 2000
Observer
Camera Primary
Site Nights Time [h] Meteors
---------------------------------------------------------------------
Juergen Rendtel
CARMEN
Marquardt
158 811.7 3,085
Sirko Molau AVIS, ESCIMO
Aachen
146 709.9 4,507
Mirko Nitschke VK1, VK2
Dresden
62 290.6 2,021
Ilkka Yrjola
NONAME
Kuusankosi
34 172.5 631
Joerg Strunk
FAMOS
Leopoldshoehe 26
149.0 858
Detlef Koschny
ICC
Noordwijkerhout 20
113.2 386
IAP team
IAP1
Kuehlungsborn
4 38.3 139
Ulrich Sperberg
ADAM
Salzwedel
2 16.1 32
---------------------------------------------------------------------
Overall
239 2301.3 11,659
Table 2 shows the monthly distribution of observations. Ignoring
August, the
number of cameras operated each month was almost constant. The
main weather
situation is best reflected by the observing time: March and July
provided
extremely poor conditions, whereas in April and since August 20
and more
nights could be used for observations each month. On top of the
list are
August and September.
The Perseids are well reflected in the number of meteor records.
However,
there is some bias since during major meteor showers more cameras
than usual
are operated. The last column gives the average number of meteors
per hour
for the two cameras operated in every clear night (AVIS, CARMEN).
Here we
can clearly see the annual variations in meteor activity.
The year starts relatively slow (the Quadrantids 2000 were
clouded out).
Shortly thereafter meteor actitivy reaches it's absolute minimum
without any
major shower in February and March. Despite the Lyrids not much
happens in
April. The May data are biased by our eta-Aquarid expedition to
Jordan, but
at least in June increasing meteor activity becomes evident. Due
to the
short nights, this is not reflected in the absolute meteor
counts, however.
By July activity has reached the all-year average thanks to a
number of
minor showers, and briefly thereafter we have the annual maximum
in August
caused by the Perseids and their long activity period. Meteor
counts drop
briefly in September, but recover in October again thanks to the
Orionids,
Taurids, and increased sporadic rates. The remainder of the year
stays
active, even though we missed both the maxima of the Leonids and
Geminids in
2000.
The net effect of all factors (duration of night, global weather
situation,
meteor activity) is that more than 80% of all meteors were
recorded in the
second half of the year. Our video data show also clearly the
daily
variations in meteor activity. On long winter evenings it may
happen, that
there is not one meteor detected in one hour, whereas in the
morning hours
there are typically more than ten meteors per hour.
Table 2: Monthly Distribution of Video Meteor Observations 2000
Month Cam Nights Time
Meteors Met/Hour
---------------------------------------------
January 5
17 190.8
679 3.2
February 3 16
137.1 391 2.8
March
4 9
52.4 101 2.0
April 5
21 182.4
429 2.4
May
4 19 107.4
342 3.4
June
3 19
93.5 286 3.2
July
5 14
60.5 339 5.1
August 8
27 342.2 2,997 8.6
September 5 28
339.2 1,601 4.9
October 5
20 217.3 1,321 6.5
November 6 25
259.9 1,354 5.3
December 5 24
318.6 1,819 6.4
----------------------------------------------
Overall 10 239 2301.3
11,659 5.0
**************************************************************************
* Dipl.-Inform. Sirko
Molau
*
*
* RWTH Aachen, Lehrstuhl fuer Informatik VI
*
__ *
* Ahornstr. 55, D-52056 Aachen,
Germany
* " 2B v 2B
" *
*
*
*
* phone:
+49-241-8021615
*
Shakespeare *
* fax :
+49-241-8888219
*
*
* email: molau@informatik.rwth-aachen.de
*
*
**************************************************************************
* www : http://www-i6.informatik.rwth-aachen.de/Colleagues/molau
*
**************************************************************************
============================
* LETTERS TO THE MODERATOR *
============================
(8) METEOROIDS
From Duncan Steel <D.I.Steel@salford.ac.uk>
Japanese meteorite finds in Antarctica story:
>A meteorite is a meteor that survives the destructive effects
of a flight
>through the atmosphere and falls to the ground whole or in
pieces.
No: A meteorite is a meteorOID that survives the destructive
effects of a
flight through the atmosphere and falls to the ground whole or in
pieces.
The term 'meteor' (synonym 'shooting star') refers to the
phenomenon seen in
the atmosphere when a meteoroid arrives. The term, then, covers
the flash of
light seen, or the train of ionisation produced, and so on. It
does NOT
refer to any solid object, either in space or on the ground.
This is according to the IAU definitions of terminology (common
dictionaries
may say something different, but specialist subjects require
specialist
jargon). In 1995 Martin Beech and I proposed that the definitions
should be
modified slightly:
M. Beech & D. Steel, "On the definition of the term
'meteoroid'," Quarterly
Journal of the Royal Astronomical Society, 36, 281-284 (1995).
The major point we were making, however, was not related to the
meteor
versus meteoroid confusion. We were concerned with the fact that
advancing
technology (i.e., NEO detection with CCDs pioneered by
Spacewatch) had led
to the point where the IAU definition of 'meteoroid'
was (and still is) inadequate, the point being that it had become
possible
to detect solid objects smaller than 100 metres in space, and so
it becomes
necessary to decide where asteroids start, and meteoroids begin.
Our
suggestion was an arbitrary dividing line at 10 metres (larger is
an
asteroid - or a minor planet in IAU parlance - while smaller is a
meteoroid).
Similarly one needs to define a lower size limit for meteoroids,
our
suggestion being 100 microns, as it is about there that solid
particles
survive entry without melting/ablating, and so do not produce
meteors. Such
tiny particles may be called 'interplanetary dust', and
'micrometeorites'
when they reach the ground.
Duncan Steel
===========
(9) SPIEGEL ARTICLE
From Hermann Burchard <burchar@mail.math.okstate.edu>
Benny:
The SPIEGEL Article about a powerful meteor explosion on 8 Nov
1999 over
Northern Germany was recorded by microbarometers, meant for
nuclear test
verification.
SPIEGEL refers to GEOPHYSICAL RESEARCH LETTERS. By clicking on
the LINK in
the SPIEGEL article, you can get the full text from there for
posting on
CCNet. It's in English. Below are publication date, volume #, and
abstract,
and here is the URL.
http://www.agu.org/GRL/articles/2000GL011859/GL11077W01.html
Best regards,
Hermann G.W. Burchard
Dept. of Mathematics
Oklahoma State University
Stillwater, OK 74078-0613
(405) 744-5690/5688 (office)
(405) 377-8919
burchar@math.okstate.edu
----------------
(10) LISTENING TO SOUNDS FROM AN EXPLODING METEOR
GEOPHYSICAL RESEARCH LETTERS, VOL. 28, NO . 1, PAGES 41-44,
JANUARY 1, 2001
Listening to sounds from an exploding meteor and oceanic waves.
L.G. Evers and H.W. Haak, Royal Netherlands Meteorological
Institute,
Seismology Division, de Bilt, the Netherlands
Received June 12, 2000, revised September 29, 2000, accepted
October 5, 2000
Abstract:
Low frequency sound (infrasound) measurements have been selected
within the
Comprehensive Nuclear-Test-Ban Treaty (CTBT) as a technique to
detect and
identify possible nuclear explosions. The Seismology Division of
the Royal
Netherlands Meteorological Institute (KNMI) operates since 1999
an
experimental infrasound array of 16 micro-barometers. Here we
show the rare
detection and identification of an exploding meteor above
Northern Germany on November
8th, 1999 with data from the Deelen Infrasound Array (DIA). At
the same
time, sound was radiated from the Atlantic Ocean, South of
Iceland, due to
the atmospheric coupling of standing ocean waves, called
microbaroms.
Occurring with only 0.04 Hz difference in dominant frequency, DIA
proved to
be able to discriminate between the physically different sources
of
infrasound through its unique lay-out and instruments. The
explosive power
of the meteor being 1.5 kT TNT is in the range of nuclear
explosions and
therefore relevant to the CTBT.
========
(11) IS JUPITER A PLANET?
From Roy Tucker <tucker@noao.edu>
"In a nutshell, Pluto likely would not be considered a
planet if it
were discovered today," said Bernie Walp, an assistant for
the
Extrasolar Planetary Search team at Berkeley.
Dear Dr. Peiser,
I've heard planets defined as dark bodies that shine by reflected
light. Jupiter radiates more energy than it receives from the
sun, although
it shines in the infrared where our eyes are not sensitive. So,
if Pluto is
not a planet because of its size, then neither is Jupiter. If
Jupiter had
been discovered today by some infrared telescope out in the
distant Oort
cloud, would we be arguing about what it was, planet or failed
star? Has
poor old Pluto become politically incorrect?
Best regards,
- Roy Tucker, asteroid observer
===============
(12) OLBERS' ANSWER
From Andrew Ferguson Nimmo <andy-nimmo@ntlworld.com>
Dear Dr Peiser,
I was astonished to read in today's CCN in "(2) SIZE MAKES
ROCK STARS DIM"
that the answer to Olbers' paradox is "because the Universe
is not old
enough for the light from most of the stars in it to have reached
us yet."
Have they thrown out the Big Bang Theory? - Or is it Einstein's
Relativity that has been thrown out?
If the Universe is not old enough for the light of most stars to
get here,
then the material in all of those stars must have shot out of the
big bang
faster than light, otherwise its light would have reached us by
now. I must
admit, I've never been too happy with Big Bang Theory, but
in this instance I suggest it might be better to throw out that
answer to
Olbers' paradox.
Also, on the Kuiper Belt objects, if these were captured from
time to time -
as I have suggested here for other Solar System objects on an
earlier
occasion - then the problem of lack of light simply wouldn't
arise. We have
no proof that everything in our Solar System was created
simultaneously.
Best wishes, Andy Nimmo.
============
(13) AND FINALLY: LABOUR PEER WARNS OF 'CRISIS' IN SCIENCE
From The Independent, 24 January 2001
http://www.independent.co.uk/news/UK/Science/2001-01/winstone240101.shtml
By Chris Hughes
The Labour peer Lord Winston warned last night of an
international crisis in
science, levelling the blame at protesters such as the fuel
lobby, arts
graduates, the press, and even fellow scientists.
Addressing the annual dinner of the Bioindustry Association, an
umbrella
group representing the biotechnology industry, Lord Winston also
hinted that
the Government might consider putting a label on drugs saying
they had been
possible only thanks to animal testing. "Maybe that's
something that
Parliament might be considering," he said.
Lord Winston said the growing suspicion of science put Britain's
economic
growth put in jeopardy, and lambasted the press for printing
"absolute
nonsense" on stem cell research. He highlighted "single
issue protest
groups" as a particular threat, accusing such groups of
distorting public
opinion via "manufactured protest".
He accused scientists of being too reluctant to engage with the
media. "Who
put their head above the parapet last week?" he asked,
referring to the
funding crisis at Huntingdon Life Sciences.
Lord Winston closed his speech saying that arts graduates
couldn't change a
"light bulb" and that he would vote against a ban on
fox-hunting, "the thin
end of the wedge".
Copyright 2001, The Independent
--------------------------------------------------------------------
THE CAMBRIDGE-CONFERENCE NETWORK (CCNet)
--------------------------------------------------------------------
The 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.