PLEASE NOTE:
*
STATEMENT BY ALAN FITZSIMMONS: A CORRECT ACCOUNT OF LEONID
RATES
From Alan Fitzsimmons <A.Fitzsimmons@Queens-Belfast.AC.UK>
Dear Dr. Peiser,
I have had an e-mail kindly forwarded to me this morning
regarding our observed Leonid count rate from La Palma.
This report contained a number of unjustified assumptions by
R. Arlt, leading to an incorrect and misleading judgment
on mine and my colleagues capabilities as observational
astronomers. I would appreciate it if you would immediately
send around the message below, in order to set the record
straight.
Best Wishes
Alan Fitzsimmons
_______________________________________________________________________________
Dr. Alan
Fitzsimmons
Tel: 01232-273124
APS
Division
Fax: 01232-438918
Dept. of Pure & Applied Physics
e-mail: a.fitzsimmons@qub.ac.uk
Queen's University of Belfast WWW: http://star.pst.qub.ac.uk/~af/
Belfast BT7 1NN
Northern Ireland
_______________________________________________________________________________
When it became obvious we had major activity over La Pama, we
realised that we should make some kind of count. Unfortunately
we did not know how to make estimates of ZHR's and other
associated parameters, as we were not experienced meteor
observers. However, even professional astronomers
know how to keep count. So we used the simplest and most
obvious solution. As there were about 6 of us, we arranged
ourselves so that we could see most of the sky between us.
We became dark adapted by standing outside for
at least 10 minutes under the photometric skies,
Then over a timed two-minute period we simply shouted
out counts when a meteor was seen (to avoid double counting).
Multiplying by 30 gave us the rough estimate of the number that
could be observed per hour over the whole sky.
So the ~1000 per hour we saw at 03:40 UT and the ~2000
per hour at 04:30 UT are if you could see the entire sky at
once. A single observer would see less than this, by perhaps
a factor 3-4, which I now believe equates to the ZHR that
is the standard measure of meteor activity.
I would appreciate you putting the record straight in an
immediate and more accurate posting. I realise that we did not
reporting the rate in what we now know as the standard manner,
and apologise for this. However we will not be libellously
accused
of inaccurate observing!
Regards
Alan Fitzsimmons
*
CCNet DIGEST, 23 November 1998
------------------------------
(1) LEONID REPORTS IN THE MEDIA POOR & WRONG
Rainer Arlt <rarlt@aip.de>
(2) ESA PUTS LEONID PICTURES ON THE WEB
Detlef Koschny <dkoschny@estec.esa.nl>
(3) OBSERVATIONS OF THE 1996 LEONID METEOR SHOWER
P. Brown et al., UNIVERSITY OF WESTERN ONTARIO
(4) HIGH SCHOOL STUDENTS DISCOVER KUIPER BELT ASTEROID
Andrew Yee <ayee@nova.astro.utoronto.ca>
======================
(1) LEONID REPORTS IN THE MEDIA POOR & WRONG
From Rainer Arlt <rarlt@aip.de>
The information about the maximum of Leonids activity given in
various press releases is poor and wrong.
FIRST: The number of 2000 meteors per hour is based on the report
of
one astronomer, who was not watching meteors primarily. He
obviously
estimated the hourly number by judging from the effect that
sometimes
several meteors were visible in one second. The impression seems
not
averaged over periods with lower activity. Fitzsimmons became a
'victim' of Poissonian statistics. ALL REGULAR METEOR
OBSERVATIONS
DURING EXACTLY THE SAME TIME SUGGEST AN HOURLY RATE OF ~500
METEORS.
SECOND: The peak is not wrong or shifted by 16 hours. The Leonids
meteoroid shower consists of two components: A storm component of
mostly faint meteors, and a background component rich in bright
meteors. The high activity observed between Nov 17.0 and 17.5 UT
was
most likely a strong background component being several
revolutions
around the Sun old. It very naturally off any prediction. THE
PEAK
THE PEAK DID OCCUR, BUT VERY INDISTINCTLY AT Nov 17.8 UT WITH
RATES OF ABOUT 150 METEORS PER HOUR.
I received hundreds of observing reports from experienced meteor
observers, which allow a very good reproduction of the actual
activity.
A similar behaviour of activity may be spotted in the scarce 1965
data
one year before the big 1996 storm. So we have a fair chance to
see the
real storm next year.
I can only ask all of you, not to spread useless information like
I
referred to above further.
Rainer Arlt
--
Rainer Arlt -- rarlt@aip.de
Director Visual Commission
International Meteor Organization
=================
(2) ESA PUTS LEONID PICTURES ON THE WEB
From Detlef Koschny <dkoschny@estec.esa.nl>
Hi,
we put some Leonid pictures on the following web page:
http://www.so.estec.esa.nl/planetary/meteors/leonids98/
Will do some animations from our video imagery tonite...
bye, Detlef.
----------------------------------------------------------------
Detlef
Koschny
email: dkoschny@estec.esa.nl
European Space Agency
ESTEC Sci/SO
Keplerlaan
1
phone: +31-71-565-4828
NL-2201 AZ Noordwijk
ZH
fax: +31-71-565-4697
================
(3) OBSERVATIONS OF THE 1996 LEONID METEOR SHOWER
P. Brown*), M. Simek, J. Jones, R. Arlt, W.K. Hocking, M. Beech:
Observations of the 1996 Leonid meteor shower by radar, visual
and
video techniques. MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL
SOCIETY,
1998, Vol.300, No.1, pp.244-250
*) UNIVERSITY OF WESTERN ONTARIO,DEPT PHYS & ASTRON,LONDON,ON
N6A
3K7,CANADA
The activity of the 1996 Leonid shower from two radars, global
visual
and single-station low-light-level TV (LLTV) observations is
presented
and summarized. Radar observations from Ondrejov in the Czech.
Republic
indicate a peak rate of (>+1) Leonids near lambda. =
235.degrees
2+/-0.1 (Equinox 2000). As observed by this radar, this peak
interval
was characterized by a significant increase in the number of
bright
Leonids as demonstrated by a noticeable lowering of the mass
index near
the peak. From radar observations in Ontario, Canada (using the
CLOVAR
system), a raw peak flux of 1.3+/-0.3x10(-2) meteoroid km(-2)
h(-1)
brighter than radio magnitude +7.7 was reached at lambda. =
235.degrees
3+/-0.1, uncorrected for initial train radius effects.
Single-station
LLTV observations suggest a peak shower flux of 1.8+/-0.4x10(-2)
meteoroid km(-2) h(-1) brighter than absolute magnitude +5+/-0.5
between 235.degrees 3 and 235.degrees 39. The position of the
radiant
on the night of maximum of the shower is found to be
alpha=152.degrees
9+/-1 degrees.0 and delta=22 degrees.1+/-1.degrees 0 from CLOVAR
observations and alpha=153.degrees 3+/-1.degrees 7 and
delta=22.degrees
1+/-1.degrees 7 from LLTV observations, Visual observations of
the
shower yield a peak zenithal hourly rate (ZHR) of 86+/-22 at
235.degrees 17+/-0.degrees 07 or an equivalent flux of
1.2+/-0.4x10(-2)
meteoroid km(-2) h(-1) brighter than absolute visual magnitude
+6.5.
The visual peak was short-lived (1.5+/-0.5 h HWHM) and richer in
fainter meteors than neighbouring intervals. Discrepancies in the
estimated absolute Leonid flux found using differing methods are
noted
and possible reasons for the differences discussed. The stream in
1996
showed two distinct meteoroid populations: a population of
recently
ejected meteoroids rich in smaller particles near 235.degrees 17
which
is very narrow in nodal extent (HWHM 0.degrees 07+/-0.degrees
02), and
an older component (of order IO revolutions in age) peaking near
235.degrees 4 which is rich in larger stream meteoroids, of long
duration (FWHM 1.degrees 2+/-0.degrees 4), which contributed most
to
the total mass flux at Earth from the stream in 1996. Copyright
1998,
Institute for Scientific Information Inc.
=====================
(4) HIGH SCHOOL STUDENTS DISCOVER KUIPER BELT ASTEROID
From Andrew Yee <ayee@nova.astro.utoronto.ca>
National Science Foundation
Media contact: Lee Herring, (703) 306-1070, kherring@nsf.gov
Program contact: Joe Stewart, (703) 306-1613, jstewart@nsf.gov
NSF PR 98-79 November 20, 1998
High School Students Discover Distant Asteroid Using NSF
Telescope and
Education Program
High school students have discovered a previously unidentified
celestial object in the Kuiper Belt using images from the
National
Science Foundation's (NSF) 4-meter Blanco Telescope in Chile.
Heather McCurdy, Miriam Gustafson and George Peterson of
Northfield
Mount Hermon School in Northfield, Massachusetts, one of six
Asteroid
Search Teams at the school participating in NSF's innovative
Hands-On
Universe Program, found and verified the distant object. It was
approximately 100 miles in diameter and now is officially called
1998
FS144.
Astronomy teacher Hughes Pack directed the students' search of
computer
images provided by the Berkeley National Lab's Supernova
Cosmology
Program. A collaborating team, Stacey Hinds and Angel Birchard,
students from Pennsylvania's Oil City Area High School, confirmed
the
location of 1998 FS144 for their peers at Northfield Mount
Hermon. The
Oil City students were led by teacher Tim Spuck, a 1998
Pennsylvania
Christa McAuliffe Fellow.
How significant is the find?
"Only about 72 such objects had been identified in the
Kuiper Belt,"
says Pack. Kuiper Belt Objects, found beyond Neptune, are
generally
believed to be remnants dating to the formation of our solar
system.
"This is a fantastic piece of science, of education, of
discovery,"
said Hands-On Universe founder and astrophysicist Carl
Pennypacker of
Lawrence Berkeley National Lab and The Lawrence Hall of Science.
He
added, "The Northfield students' discovery has shown that
all students
from a broad range of backgrounds can make solid, exciting and
inspiring scientific contributions."
"These students had the opportunity to operate like real
astronomers,"
said NSF program officer Joseph Stewart. Star images were
obtained by
the students via computer from Cerro Tololo Inter-American
Observatory
in Chile, Stewart said. Students then used visual inspection and
special Hands-On Universe software.
"One of the historically limiting factors in astronomy has
been simply
not having enough eyes available to inspect all the useful images
that
astronomers collect," he said, "but, it's very exciting
that these kids
are contributing to real science, performing actual science in
the
classroom!" They are able to measure the distance of stars
and track
supernova, for example.
"This generous sharing of data by the Supernova Cosmology
Program
scientists," said Pack, "is serving dual purposes,
because scientists
at the Supernova Cosmology Group are using the data to find
supernova
while students use the same data to search for very faint
asteroids."
"The Kuiper Belt has the potential to tell us a great deal
about how
the solar system originated and evolved and how it compares to
others,"
says Brian Marsden of the Minor Planet Center in Cambridge,
Massachusetts. Marsden received the data from Pack and confirmed
the
discovery.
Begun in 1990, Hands-On Universe is now based at the University
of
California-Berkeley in the Lawrence Hall of Science. Cerro Tololo
Inter-American Observatory is one of four divisions of the
National
Optical Astronomy Observatories (NOAO), operated by the
Association of
Universities for Research in Astronomy (AURA), Inc., under
cooperative
agreement with NSF.
-NSF-
For pictures of KBO 1998 FS144 see: http://astronomy.geecs.org.
For
more information on the Hands-On Universe Project see:
http://hou.lbl.gov.
----------------------------------------
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----------------------------------------
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contact the moderator Benny J Peiser at <b.j.peiser@livjm.ac.uk>.
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*
CCNet DEBATE, 23 November 1998
------------------------------
(1) ASTROBIOLOGY & PANSPERMIA
Chandra Wickramasinghe <xdw20@dial.pipex.com>
& Sir Fred Hoyle
(2) WHEN QUANTITY TURNS QUALITY
Andy Nimmo <andy.nimmo@net.ntl.com>
(3) LIFE BRINGING IMPACTS
Michael Paine <mpaine@tpgi.com.au>
(4) ASTEROID IMPACTS & STAR TREK: WHO INVENTED DEFLECTION
IDEA?
Richard Kowalsky <bitnik@bitnik.com>
====================
(1) ASTROBIOLOGY & PANSPERMIA
From Chandra Wickramasinghe <xdw20@dial.pipex.com>
& Sir Fred Hoyle
Dear Benny:
Andrew Glikson's comments reveal an unfortunate ignorance of the
issues
that are being addressed by modern proponents of panspermia, and
arrogance to imply that he, or they, the panspermia opponents,
know
best. The fact is that neither panspermia nor the theory of an
indigenous terrestrial origin of life is proved, and both
theories are
clearly worthy of the fullest possible scientific
exploration. This is
not the place to discuss technical arguments in detail, so we
would
like to advise Dr. Glikson to take some time to study the
evidence as
for instance in our writings, or visit the panspermia website at
http://www.panspermia.org
<http://www.panspermia.org>
as well as our
own website which lists our publications at
http://www.cf.ac.uk/uwc/maths/wickramasinghe/
Here are some brief comments on the several several points that
have
been made:
1. Spectroscopy of interstellar and cometary dust is consistent
with a
vast cosmic preponderance of complex organic materials that
cannot be
distinguished from biomaterial or their degradation
products. Since
some 1 in 3 or 4 carbon atoms in interstellar space are tied up
in the
form of such material one could reasonably argue that microbial
processes, which are incomparably better suited to accomplish
this feat
than any abiotic process, may be at work.
2. The panspermia hypothesis is fully consistent with the known
survival limits of extremophiles and of DNA. Of course
bacteria/DNA/organics would not survive in sungrazing comets, but
that
is a totally spurious point. Such experiments as we have been
able to
get done show clearly that flash heating upon atmospheric entry
does
not lead to the wholesale destruction of submicron-sized
microorganisms. Moreover, bacteria present in the interiors of
large
clumps would survive almost indefinite periods of exposure to an
ultraviolet radiation field. In any event, the survival of the
panspermia hypothesis itself requires less than 1 microorganism
in some
10^20 derived from interstellar space to remain viable at every
solar
system/comet-forming event.
3. If the odds against starting life de novo on a planet like the
Earth
are superastronomical as we estimate them to be, an insistence on
a
terrestrial origin implies a return to pre-Copernican thinking.
Furthermore, all the indications from modern microbiology are
that once
started microbial life is equipped with all the right attributes
to
survive and spread on a cosmic scale.
4. We do not propose to comment on the UFO-Panspermia analogy, a
comparison that is unfortunate to say the least. It is high
time that
Glikson and our other critics recognised that science is
ultimately
concerned with facts, not ill informed and unqualified prejudice.
Chandra Wickramasinghe
Fred Hoyle
21 November 1998
==================
(2) WHEN QUANTITY TURNS QUALITY
From Andy Nimmo <andy.nimmo@net.ntl.com>
Dear Sir,
I must admit that I was utterly astonished by Dr Andrew Glikson's
comment that "it is well known that the distinction between
organic
matter and bacterial life forms is not a quantitative one but a
qualitative quantum jump." While I am sure nobody would
quibble with
his assertion that the distinction is qualitative, does he not
realize
that in some instances quality can depend on quantity?
This is, and must always be the case, wherever the mathematics of
probability arises, as it must do in this case. As Chandra
Wickramashinghe and Sir Fred Hoyle have pointed out in the
past, there
are few places in our Universe where so many atoms can find
themselves
sufficiently juxtaposed to form complex molecules as on the
surface of a
heliosphere.
If, as has been suggested, this is where comets are formed,
irrespective of in which circumstances, then the probability of
molecules as complex as those necessary to harbour potential life
is
almost certainly much greater in comets than anywhere else, even
if the
molecules then have to be carried on comet particles to drop into
a
suitable atmosphere, before they can flourish.
Let us hope that the STARDUST mission, can either verify or put
this
matter to rest.
Andy Nimmo.
==================
(3) LIFE BRINGING IMPACTS
From Michael Paine <mpaine@tpgi.com.au>
Dear Benny,
For an interesting discussion of panspermia and other theories on
the
origin of life see the new book "The Fifth Miracle" by
Paul Davies. Also
I have a web site which covers the issue of transfer of microbes
between
planets via impact ejecta:
http://www1.tpgi.com.au/users/tps-seti/swaprock.html
This is a different issue to interstellar panspermia.
Regards
Michael Paine mailto:mpaine@tpgi.com.au
=======================
(4) ASTEROID IMPACTS & STAR TREK: WHO INVENTED DEFLECTION
IDEA?
From Richard Kowalsky <bitnik@bitnik.com>
It's cloudy again and the Mrs. has gone to bed, so I have some
time to
watch Star Trek on the Sci-Fi Channel.
Tonight's episode is the one about the planet that has the North
American "Indians" living in a near perfect
environment. The Enterprise
has been sent to divert an asteroid from impacting and
killing all
life on this planet.
There is a scene, just after Kirk falls inside the asteroid
deflecting
obelisk, where Spock explains to McCoy that they can no longer
look for
Kirk because every moment they wait to deflect the asteroid, the
harder
it becomes to do the job. Even to the point where even a starship
isn't
powerful enough.
I would say, the only things I noted that was incorrect was that
there
was a specific "deflection point", meaning it had to be
done at a
certain distance from the planet... Not before or after. McCoy
also
questions Spock because the asteroid will not impact for 2
months,
which is kind of a short time span to deflect, especially for a
"planet
killer"
Actually the explaination of asteroid deflection is extremely
lucid and
accurate, even today, 30 years later.
Evidently they did get some good scientific information on the
subject
for this episode. (They got alot of things right, but that's off
topic)
That brings to mind the question of exactly how old is this idea?
IOW, when was the idea of deflecting a possible impactor first
put forward
and by whom?
richard
----------------------------------------
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educational
use only. The attached information may not be copied or
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