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#17737 From: GeoZay@...
Date: Tue Dec 26, 2000 11:10 am
Subject: Re: (meteorobs) Meteorites and Terminal velocity
GeoZay@...
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Dave>> Your point about recrystalization from reheating has merit but I
believe that to form smaller crystals the iron meteorite would have to
completely melt (2795 o F  or 1535 o C ) then all of the meteorite would
have the same very small crystals that make up the fusion crust.<<

I can think of at least one instance where melting doesn't have to occur to
have crystal structure changes in heated iron. The process of making cold
chisels. It's been a long time since I've made one, but do recall that you
heat up the shaped piece of iron to a red hot temperature and then dip it
into cold water. This process results with a changed crystal structure and
very hard metal. No melting was involved.
GeoZay


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#17736 From: "Marco Langbroek" <marco.langbroek@...>
Date: Tue Dec 26, 2000 2:35 pm
Subject: Re: (meteorobs) Meteorites and Terminal velocity
marco.langbroek@...
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Hi Dave, George,

The "glow in the dark" has been reported a number of times notably with
irons. It need not have to do with radiating heat - Spratt some years ago
proposed an incandescent effect through recombining ions on the irons
surface, a form of natural thermoluminiscence.

Something I would like to offer as a source for some warmth with fresh
falls, is the decay of very short-lived radioactive nuclei formed by cosmic
irradiation while the stone was still in space. Perhaps the decay could
generate some warmth up to a point that it is notable by the touch directly
after the fall. Perhaps this could generate some of the reported
luminiscence. Please note, this is pure conjecture. I never thought of that
before this discussion on meteorobs started - ought to ask this to one of my
professional meteoriticist friends!

Reheating evidence in meteorites certainly has been searched for.
There's no evidence from meteorites that heating effects altered the
material for more than a few millimeters below the surface. In normal irons,
a profound reheating would destroy the Widmanstatten patterning they
display. In stones, for example chondrules would be lost in such a case.
Strong heating to deep depths into the meteorite therefore did not occur.

I would like to point out also that there is no authenticated case of a
meteorite  hot enough to be able to start a fire - while many landed into
matter well combustable, e.g. Spratt gives the example of the Forest City
landing in a haystack.

- Marco Langbroek

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#17735 From: Dave English <prospector@...>
Date: Mon Dec 25, 2000 10:54 pm
Subject: Re: (meteorobs) Meteorites and Terminal velocity
prospector@...
Send Email Send Email
 
George,

      Your point about recrystalization from reheating has merit but I
believe that to form smaller crystals the iron meteorite would have to
completely melt (2795 o F  or 1535 o C ) then all of the meteorite would
have the same very small crystals that make up the fusion crust.

      Your point has inspired a question that perhaps scientists should
investigate, maybe they have, of the effects reheating would have on other
inclusions that can be found in iron and stony meteorites. The morphology
of some meteorites and targeted inclusions from reheating could be
significant and detectable if investigated.  The 1885 Biela iron meteorite
  (the Mazapil Meteorite) we discussed within the last two years would be a
good meteorite to investigate, it had the normal inclusions and was
reported to be glowing from12 inches down its impact hole.

      Upon re-reading a part of the story, spectrographs of meteors during
the shower in which the meteorite fell, (yes, 1885) match very well the
iron and carbon showing in a spectograph of the meteorite. Thought Ed,
Peter and others might appreciate that.   "Is It A Piece of Comet?", The
Century Magazine, Aug 1887,  by William E. Hidden, if anyone wants to
look it up.

      As for Marco's comment, I've had to drop iron tools that had gotten too
hot in the sun but the reports we are concerned with are about freshly
fallen meteorites that have been variously reported as frosty, cold, warm,
hot or even glowing with heat just after landing. I believe all are possible
depending on circumstances for each individual meteorite.

                                                    Dave English
                                                    Oceanside, California

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#17734 From: "Marco Langbroek" <marco.langbroek@...>
Date: Mon Dec 25, 2000 7:59 pm
Subject: (meteorobs) re: meteorite temperatures
marco.langbroek@...
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Hi,

A few days ago there was some discussion on this list about free fall
temperatures of meteorites and reports of warm to the touch fresh falls. I
have a partial explanation  to offer.

Physically, these hot meteorites upon impact should not be possible. During
dark flight the meteorites' velocity is well below the speed of sound and
the airflow should actually cool the object rather than warm it. Still there
are many of such reports (but, please note, also some of icy cold, even
frost covered meteorites!!) so we should not neglect it. Perhaps something
else is going on.

But there also is a very down to earth explanation of at least some of these
reports. I literally touched upon this some years ago when I photographed a
fussion crust covered fragment of Mbale. For that purpose I placed it in
bright sunlight and made my photographs. When I took up the fragment I
almost dropped it again: it felt very warm and my initial response was to
retract my fingers in order not to burn them. A second touch reveiled the
meteorite to be warm, but not as "hot" as my initial nerve system reaction
suggested. Mind you, this was some 2 years after this fragment had
fallen.....

The solution is simple. Fussion crusts are black. They absorp sunlight and
radiate that as warmth. Only a few minutes of exposure to a summer sun is
enough to warm it noticably. It is the same effect well known to those who
go sit on a dark painted park bench in summer, or tread on tarmac bare feet
in summer.

This explains at least some of the reports, although perhaps not all.

By the way, in my task of checking meteorite falls and finds reported to the
Dutch Meteor Society I have had a report of an object being "hot too the
touch" upon a presumed fall once or twice, most recently last October (with
the dog reportedly burning its nose) - but in all cases, the material was
not a meteorite but terrestrial. Imagination does a lot, especially if
people expect something to be hot.

- Marco Langbroek

---
Marco Langbroek                    private: marco.langbroek@...
Leiden University                     work: m.langbroek@...
Faculty of Archaeology
P.O. Box 9515
NL-2300 RA Leiden
The Netherlands

"What seest thou else
   In the dark backward and abysm of time?"

William Shakespeare: The Tempest act I scene 2
---




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#17733 From: Rainer Arlt <rarlt@...>
Date: Mon Dec 25, 2000 4:53 pm
Subject: (meteorobs) [IMO-News] IMO shower circular URSIDS
rarlt@...
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Date: Mon, 25 Dec 2000 12:32:50 MET
Subject: [IMO-News] IMO shower circular URSIDS



                -------------------------------------

                I M O   S h o w e r   C i r c u l a r

                -------------------------------------


                        U R S I D S   2 0 0 0



The 2000 return of this shower was eagerly awaited because an enhanced
activity was expected. Indeed, the rates were significantly higher than
the average. The last reported Ursid activity enhancement occurred on
Dec. 22, 1996 at solar long. 270.7 with ZHR of the order of 30.

In 2000 the conditions were good as the Moon was almost new. The long
northern nights allow a good overlap. Unfortunately, this first summary
indicates that the most interesting period is not well covered. Most
European observers had to finish around 6h UT (morning twilight). The
number of North American data is scarce so far. As a consequence, we
cannot yet achieve a good profile. Below find the preliminary data.
The high ZHR at the end agrees with Japanese data published here before,
although the errors are still quite large.

We are very grateful to the following 15 observers who sent in their reports
in time for this first activity overview:

ARLRA Rainer Arlt (Germany)
BADPI Pierre Bader (Germany)
BUCAN Andreas Buchmann (Switzerland)
CANED Ed Cannon (USA)
ENZFR Frank Enzlein (Germany)
HOSDA Dave Hostetter (USA)
LANMA Marco Langbroek (Netherlands)
LUNRO Robert Lunsford (USA)
LUTHA Hartwig Luthen (Germany)
MOLSI Sirko Molau (Germany)
OSAKA Kazuhiro Osada (Japan)
PUNMI Milesh Puntambekar (India)
RENJU Jurgen Rendtel (Germany)
STOEN Enrico Stomeo (Italy)
ZHUJI Jin Zhu (China)


------------------------------------------------------
Date   Time (UT)  Sollong nObs nIND  nURS     ZHR
------------------------------------------------------
Dec 22    0240    270.553   5    4     16   5.1 +- 1.2
     22    0330    270.586  12    9     46   8.2    1.2
     22    0410    270.620  16    9     76  12.7    1.5
     22    0510    270.658  16   10    104  19.6    1.9
     22    0535    270.676   8    6     58  26.1    3.4
     22    0935    270.847   2    2     29  53     10

Solar longitudes refer to equinox J2000.0. nObs is the number of
individual observing periods, nIND is the number of individual
observers providing them, nURS is the number of Ursids seen. The
population index used was r=2.5. The expectation value of the ZHR,

ZHR = (1 + sum nGEM) / sum(Teff/C),

was used for the averages here, where Teff is the effective observing
time and C is the total correction composed of limiting magnitude,
clouds, and zenith correction [sin (h_R)]. Times are rounded to the
nearest 10 minutes.


Juergen Rendtel

25 Dec 2000


************************************************************************
Juergen Rendtel                          Astrophysical Institute Potsdam
jrendtel@...                                      Telegrafenberg A 27
Phone: (+49) 331 - 288 2327 (office)              14473 Potsdam, Germany
Fax:   (+49) 331 - 288 2310
http://aipsoe.aip.de/~rend/rnl-p.html

				        International Meteor Organization
Phone: (+49) 33208 - 50753  (priv.)   Seestr.6, 14476 Marquardt, Germany
************************************************************************

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----- End of forwarded message from Juergen Rendtel -----

--
Rainer Arlt  --  Astrophysikalisches Institut Potsdam -- www.aip.de
Visual Commission - International Meteor Organization -- www.imo.net
rarlt@... --  phone: +49-331-7499-533  --  fax: +49-331-7499-526

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#17732 From: Peter Jenniskens <pjenniskens@...>
Date: Mon Dec 25, 2000 3:18 pm
Subject: (meteorobs) First results from the visible spectroscopy of an outburst Ursid meteor
pjenniskens@...
Send Email Send Email
 
First results from the visible spectroscopy of an outburst Ursid meteor
(Dec. 24, 2000):

Observations of the December 22 Ursid outburst show that the relatively
fresh ejecta of comet 8P/Tuttle bear much resemblance in morphology to
the similarly fresh Leonid storm dust of comet 55P/Tempel-Tuttle.
Both show an early release of sodium atoms, relative to magnesium atoms,
thought to
be caused by a falling appart in many fragments after entering the Earth's
atmosphere
and thus exposing volatile minerals.

Further reading: http://www-space.arc.nasa.gov/~leonid/leonidnews30.html
               or http://leonid.arc.nasa.gov/leonidnews30.html

The WGN paper predicting the 2000 Ursid outburst is now available in html
form as well,
with thanks to Mike Koop:

http://www-space.arc.nasa.gov/~leonid/ursids.html


Peter Jenniskens

#17731 From: Masaaki TAKANASHI <takanashi@...>
Date: Mon Dec 25, 2000 2:50 pm
Subject: (meteorobs) Ursids in Japan : visual observation results -Update-
takanashi@...
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Ursids 2000 prompt report -Update-
Visual results in Japan (The Nippon Meteor Society).

ZHR has been computed with:
-  gamma = 1.0 (correction of Radiant elevation)
-  r = 2.5  (equal "IMO Shower Circular")
-  excluding:observations under unfavourable condition
    (T<30m, Lm<4.5mag, Cl>0.4, RP-h<10deg)
-  Err. : ZHR * 1/SQRT(#URS)

r(population index) number changed. (3.0 -> 2.5)

Hourly ZHR
----------------------------------------------------------------
Time[UT]    SunL   Obs  T.eff  #URS   ZHR   Err.  (HR)   Remarks
----------------------------------------------------------------
Dec. 2000
21d 12:30  269.959   1   1.25     1     5     5  (  1)
21d 13:30  269.991   1   1.00     2    10     7  (  2)
21d 14:30  270.033   2   1.83     3     6     3  (  2)
21d 15:30  270.076   3   3.00     4     4     2  (  1)
21d 16:30  270.118   2   2.00     3     4     3  (  2)
21d 17:30  270.161   2   2.00     4     6     3  (  2)
21d 18:30  270.203   2   1.50     2     4     3  (  1)

22d 08:45  270.808   4   2.00    13    42    12  (  7)
22d 09:30  270.840  10   8.78    73    41     5  (  8)
22d 10:30  270.882  10   9.13    56    25     3  (  6)
22d 11:30  270.925   6   6.00    45    26     4  (  8)
22d 12:30  270.960   4   2.83    15    17     4  (  5)
22d 13:30  271.010   2   2.00    12    10     3  (  6)
22d 14:30  271.052   8   7.75    20    12     3  (  3)
22d 15:30  271.095   4   4.00     8     2     1  (  2)
22d 16:30  271.137   3   3.00    12     6     2  (  4)
22d 17:30  271.180   2   2.00     8     3     1  (  4)
22d 18:30  271.222   2   1.50    10     6     2  (  7)
22d 19:30  271.264   3   3.00    11     4     1  (  4)
22d 20:30  271.307   3   2.67    11     6     2  (  4)

23d 12:30  271.986   1   1.00     2     8     6  (  2)
23d 13:30  272.029   2   1.67     2     3     2  (  1)
23d 14:30  272.071   2   1.75     1     2     2  (  1)
23d 15:30  272.114   0    -       -     -     -  (  -)
23d 16:30  272.156   0    -       -     -     -  (  -)
23d 17:30  272.198   0    -       -     -     -  (  -)
23d 18:30  272.241   1   1.00     2     4     2  (  2)
23d 19:30  272.283   3   3.33     3     2     1  (  1)
23d 20:30  272.326   3   2.83     3     2     1  (  1)
----------------------------------------------------------------

Observers (24members) :
Seiji AKAGI, Daiyu ITO, Hiroyuki KATO, Noriko KOBAYASHI, Wakaba KOBAYASHI,
Kumiko KOUSAKA, Karimu KURAGAKI, Katsuhiko MAMETA, Yukihisa MATSUMOTO,
Hidekastu MIZOGUCHI, Minoru MURAKI, Tetsuya NAKAMURA, Yoshiko NAKAZAWA,
Hiroyuki NISHIMOTO, Kazuhiro OSADA, Mitsue SAKAGUCHI, Satoshi SAKAI,
Koetsu SATO, Mikiya SATO, Tomoko SATO, Yasuo SHIBA, Kazuhiro SUMIE,
Masafumi SUZUKI, Yasuhiro TONOMURA

Total observations          :  4,730 min. (= 78.83h)
Total number of URS meteors :    326

See more details showing at :
      http://www.nms.gr.jp/en/index.html
      http://www.nms.gr.jp/nmsnews_e.html
      http://www.nms.gr.jp/urs0001.gif

-----------------------------------------------------------------------
Masaaki Takanashi  (The Nippon Meteor Society / Gotemba city, JAPAN)
                                    E-Mail : takanashi@...
The Nippon Meteor Society's Web page : http://www.nms.gr.jp/en/
  (New URL! Please change your bookmark and linkspot in your Web site.)
-----------------------------------------------------------------------

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#17730 From: Peter Jenniskens <pjenniskens@...>
Date: Mon Dec 25, 2000 2:48 pm
Subject: (meteorobs) First results from the visible spectroscopy of an outburst Ursid meteor
pjenniskens@...
Send Email Send Email
 
First results from the visible spectroscopy of an outburst Ursid meteor
(Dec. 24, 2000):

Observations of the December 22 Ursid outburst show that the relatively
fresh ejecta of comet 8P/Tuttle bear much resemblance in morphology to
the similarly fresh Leonid storm dust of comet 55P/Tempel-Tuttle.
Both show an early release of sodium atoms, relative to magnesium atoms,
thought to
be caused by a falling appart in many fragments after entering the Earth's
atmosphere
and thus exposing volatile minerals.

Further reading: http://www-space.arc.nasa.gov/~leonid/leonidnews30.html
               or http://leonid.arc.nasa.gov/leonidnews30.html

Peter Jenniskens

#17729 From: zj@...
Date: Mon Dec 25, 2000 2:27 am
Subject: Re: (meteorobs) No Ursids Here, and Merry Christmas!
zj@...
Send Email Send Email
 
> No Ursids were seen this year from here as I have been sick with the flu
> since peak night....perfect timing! :(  Am dragging myself out of bed
> tonight though in hopes of seeing Saint Nick..........

Mark,

We had bad weather at the peak night, and white snow before Christmas in
Xinglong, while it was clear in Beijing.

Wish you recovery from the flu quickly.

Merry Christmas and Happy New Millennium!

Jin
--
========================================================================
Jin Zhu                          | Tel.:  +86-10-62751286 (O)
Beijing Astronomical Observatory |        +86-314-5220267 (Schmidt dome)
Chinese Academy of Sciences      | Pager: +86-10-96301682333
P. R. China                      | Fax :  +86-10-62765031
------------------------------------------------------------------------
Room 2919, No. 2 Science Building, CAS-PKU Beijing Astrophysics Center,
Peking University, Beijing 100871, P. R. CHINA.
------------------------------------------------------------------------
email: zj@...                  http://vega.bac.pku.edu.cn/~zj
========================================================================
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#17728 From: Casper ter Kuile <casper.ter.kuile@...>
Date: Mon Dec 25, 2000 1:36 am
Subject: (meteorobs) Ursids 2000 on DMS-website
casper.ter.kuile@...
Send Email Send Email
 
Hi everyone!

The Ursids are extremely well observed from the Netherlands.
We experienced one of those very rare periods with totally clear skies all
over the country!
Sky transparancy was excellent and air utmost dry without any change on fog
during the night.
So lots of DMS-observers with their equipment went out to observe the
Ursids to find out if the predicted outburst would materialize.
To put things short we invite you to have a look at the DMS-website at
http://www.dmsweb.org where have put lots of observations including
discussions together.
Please enjoy the christmas outfit of the website too!

Very best wishes to all of you and have a merry christmas,

Casper.


Casper ter Kuile, Dutch Meteor Society (DMS)
Akker 145, NL-3732 XD, De Bilt, The Netherlands
Tel. +(31)-30-2203170, Fax. +(31)-30-2202695, XOIP: 0208699068
GSM-BEN: +(31)-6-24242445, GSM-KPN: +(31)-6-20247982
E-mail_1: casper.ter.kuile@...
E-mail_2: casper.ter.kuile@...
E-mail_3: webmaster@...
DMS website: http://www.dmsweb.org
Mirrorsite: http://home.wanadoo.nl/dms

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#17727 From: Mark Davis <MeteorObs@...>
Date: Sun Dec 24, 2000 11:25 pm
Subject: (meteorobs) No Ursids Here, and Merry Christmas!
MeteorObs@...
Send Email Send Email
 
No Ursids were seen this year from here as I have been sick with the flu
since peak night....perfect timing! :(  Am dragging myself out of bed
tonight though in hopes of seeing Saint Nick..........

M E R R Y   C H R I S T M A S!!!!!

-Mark


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#17726 From: "Richard Taibi" <rjtaibi@...>
Date: Sun Dec 24, 2000 9:53 pm
Subject: (meteorobs) A job well done!
rjtaibi@...
Send Email Send Email
 
Hi Everyone,
    Although the Ursid data is disappointing to some of us and confusing to
most of us, at least there IS data!  We can be proud of obtaining the best
set of Ursid observations ever.  In previous years, the number of visual
observers could be counted on one hand, if anyone observed at all.  This
year there were twenty-or-so data contributors, and some observations were
made by means other than visual.  The response of the worldwide meteor
enthusiast community was really impressive.
    Now those who made predictions based on orbital dynamics considerations
can sort through the data and make some conclusions.  Most likely, not
everyone will agree with all the conclusions.  But, this will provide the
motivation for mounting 2001's observational campaign.  Better questions and
refined means of answering them will result from what was seen this year.
This is the way Science proceeds, isn't it?
    We have done a good job and advanced the study of the Ursids!

    Richard Taibi

_________________________________________________________________
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#17725 From: Skywayinc@...
Date: Sun Dec 24, 2000 2:56 pm
Subject: (meteorobs) CHRISTMAS DAY SOLAR ECLIPSE WEATHER OUTLOOK
Skywayinc@...
Send Email Send Email
 
Here is our nationwide weather outlook for viewing the Christmas Day
partial eclipse of the Sun that will be occurring across much of North
America.  The eclipse will be reaching its peak at roughly 16:20 UTC along
the west coast of the US; 16:30 UTC for the west coast of Canada; 17:10 UTC
for central sections of North America; 17:45 UTC for the east coast of the
US; and 18:00 to 18:15 for Canadian Maritimes.  Greatest coverage (a
magnitude of 72.3%) will occur from Baffin Island in far-northern Canada,
with coverage decreasing as one heads to the south.   Most of North America
will witness this event with the exception of northwestern Canada and Alaska.

BEST VIEWING WEATHER:

Virginia and the Carolinas in the eastern US; southern and central California
and southwestern Arizona in the western US.  In these areas, 0 to 2/10ths
cloud coverage is expected, making for excellent visibility of the eclipse.

GOOD VIEWING WEATHER:

Most of the eastern US, to the east of the Mississippi River should get good
views.  Exceptions will be near and around the Great Lakes where localized
heavy snow showers and flurries may occur thanks to very cold air flowing
across the Lakes.  Another exception would be the Adirondacks of northern New
York and much of central and northern New England, where clouds and scattered
flurries will also be possible.

In the western US, northern California, southern Oregon, southwest Idaho,
western Nevada and much of Arizona (except the northeast part) should also
have good views.

In localities deemed "good", cloud cover will range from 3/10 to 6/10th
coverage, meaning that while clouds will occasionally block the Sun, more
often than not, the Sun will be clearly visible and allow for good viewing.

FAIR TO POOR WEATHER

All those regions not mentioned above are likely to fall into this category,
with widespread unsettled weather expected.  This includes much of the
northern and central Great Plains, Texas-Oklahoma, the Rocky Mountains and
the desert southwest.  Cloud coverage will range from 7/10th to 10/10th
coverage, meaning that while in some areas fortuitous holes and breaks in the
cloud cover might afford some views of the partially eclipsed Sun, more often
than not the view is likely to be obscured.

Regardless of the weather in your area, we wish you all a very happy and safe
holiday season!

Joe & Renate Rao
Skyway, Inc.
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#17724 From: Skywayinc@...
Date: Sun Dec 24, 2000 2:44 pm
Subject: (meteorobs) CHRISTMAS DAY SOLAR ECLIPSE WEATHER OUTLOOK
Skywayinc@...
Send Email Send Email
 
Here is our nationwide weather outlook for viewing the Christmas Day
partial eclipse of the Sun that will be occurring across much of North
America.  The eclipse will be reaching its peak at roughly 16:20 UTC along
the west coast of the US; 16:30 UTC for the west coast of Canada; 17:10 UTC
for central sections of North America; 17:45 UTC for the east coast of the
US; and 18:00 to 18:15 for Canadian Maritimes.  Greatest coverage (a
magnitude of 72.3%) will occur from Baffin Island in far-northern Canada,
with coverage decreasing as one heads to the south.   Most of North America
will witness this event with the exception of northwestern Canada and Alaska.

BEST VIEWING WEATHER:

Virginia and the Carolinas in the eastern US; southern and central California
and southwestern Arizona in the western US.  In these areas, 0 to 2/10ths
cloud coverage is expected, making for excellent visibility of the eclipse.

GOOD VIEWING WEATHER:

Most of the eastern US, to the east of the Mississippi River should get good
views.  Exceptions will be near and around the Great Lakes where localized
heavy snow showers and flurries may occur thanks to very cold air flowing
across the Lakes.  Another exception would be the Adirondacks of northern New
York and much of central and northern New England, where clouds and scattered
flurries will also be possible.

In the western US, northern California, southern Oregon, southwest Idaho,
western Nevada and much of Arizona (except the northeast part) should also
have good views.

In localities deemed "good", cloud cover will range from 3/10 to 6/10th
coverage, meaning that while clouds will occasionally block the Sun, more
often than not, the Sun will be clearly visible and allow for good viewing.

FAIR TO POOR WEATHER

All those regions not mentioned above are likely to fall into this category,
with widespread unsettled weather expected.  This includes much of the
northern and central Great Plains, Texas-Oklahoma, the Rocky Mountains and
the desert southwest.  Cloud coverage will range from 7/10th to 10/10th
coverage, meaning that while in some areas fortuitous holes and breaks in the
cloud cover might afford some views of the partially eclipsed Sun, more often
than not the view is likely to be obscured.

Regardless of the weather in your area, we wish you all a very happy and safe
holiday season!

Joe & Renate Rao
Skyway, Inc.
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#17723 From: peter.atanackov@...
Date: Sun Dec 24, 2000 8:05 pm
Subject: Re: (meteorobs) Re: Happy Holidays
peter.atanackov@...
Send Email Send Email
 
It's *the* time of the year and time again to thank  everyone for making
this list as interesting as it is. Lew, keep up the great work! Thanks
also to all observers for sharing their experiences! Thanks for all the
theoretical radiants, meteor outburst predictions and all the 'stupid'
questions that made the list all more interesting.

May the Cloud Gods be kind to all of you in the New Millenium!

Clear skies, Merry Christmas and a Happy Y2K+1!

Jure A.

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#17722 From: Robert Lunsford <lunro.imo.usa@...>
Date: Sun Dec 24, 2000 7:38 pm
Subject: (meteorobs) Re: Happy Holidays
lunro.imo.usa@...
Send Email Send Email
 
As one of the 500 members of this list I am happy to hear that we can
brighten anybody's life by sharing our knowledge, opinions, and
observing experiences. It is notes like yours that make all of this
effort well worth it. Many thanks for taking the time to express your
thanks.

Happy Holidays to you and best wishes in 2001!

Sincerely,

Robert Lunsford


BlueGreenStarz@... wrote:
>
> Dear sir,
>
> I don't know how to make a new topic for this group, so I hope this is
> ok.
>
> I am a disabled person who cannot go out and watch the night skies as
> I once
> could, so I just wanted to thank everyone for sharing all of their
> experiences and insights. It sure does mean a great deal.
>
> Happy Holidays. :)
>
> Thank you!
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#17721 From: BlueGreenStarz@...
Date: Sun Dec 24, 2000 12:27 pm
Subject: Re: (meteorobs) Weekly IRC Meteor Chat on Monday!
BlueGreenStarz@...
Send Email Send Email
 
Dear sir,

I don't know how to make a new topic for this group, so I hope this is ok.

I am a disabled person who cannot go out and watch the night skies as I once
could, so I just wanted to thank everyone for sharing all of their
experiences and insights. It sure does mean a great deal.

Happy Holidays. :)

Thank you!

#17720 From: "Rosely Gregio" <gregio@...>
Date: Sun Dec 24, 2000 5:18 pm
Subject: (meteorobs) Merry Christmas
gregio@...
Send Email Send Email
 
For You and All Yours, Merry Christmas with a lot of Paz, Love, Wisdom,
Humility, and that the LIGHT coming of the Sky Illuminates its best
thoughts, so that all together ones can begin a New Millennium and more one
Century with a lot of accomplishments, health, and Paz in the Earth among
All the Men! That the Science never accomplishes before progresses reached
for the good of everybody and of Our Small Blue Planet! That Its Dreams
become the more it completes Reality!
Of Christmas hugs!!!
Rosely Gregio - Br
Clean sky for everybody

Rosely - Br.
gregio@...
http://members.nbci.com/Rosely/Index.htm
http://membro.intermega.com.br/rgregio/
http://construindobjetos.na-web.net



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#17719 From: "Ed Majden" <epmajden@...>
Date: Sun Dec 24, 2000 4:55 pm
Subject: (meteorobs) Seasons Greetings
epmajden@...
Send Email Send Email
 
Seasons Greetings to all and may you be blessed with clear skies in 2001!

Ed Majden
Courtenay B.C.
Canada

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#17718 From: Rainer Arlt <rarlt@...>
Date: Sun Dec 24, 2000 1:13 pm
Subject: (meteorobs) VMDB 1999 available
rarlt@...
Send Email Send Email
 
---------------------------

The Visual Meteor Database:
  VMDB FILES 1999 AVAILBLE

---------------------------


The 1999 files of meteor observations as collected by
the Visual Commission of the International Meteor
Organization are closed. Due to the extraordinary
amount of data, the issue has been delayed to the
end of 2000.

Extracts of the original dBase files can be found at

    http://www.imo.net/visual/vmdb.html

A printed version of the data will be shipped together
with the December issue of WGN, the Journal of the IMO.
The original dBase files contain additional information
on 'plotting/counting'. They are available on request.


The enormous number of incoming observations requires
efficient processing. Please make sure your observing
form is similar to what is given at

    http://www.imo.net/visual/imoform.html

Do not send office file formats such as Word documents
or Excel sheets, as these are unreadable on other
computer systems. Remember that the number of observing
periods in 1999 was 22137; if each of them takes only
2 minutes to process, I need 738 hours to utilize them.
That means I have to spend 2 hours on the VMDB EVERY
DAY. Hence, please do not increase the workload with
file processing.


Rainer Arlt


--
Visual Commission -- International Meteor Organization -- www.imo.net
visual@... --  phone: +49-331-7499-533  --  fax: +49-331-7499-526

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#17717 From: Sirko Molau <molau@...>
Date: Sun Dec 24, 2000 12:04 pm
Subject: (meteorobs) forward video data, please!
molau@...
Send Email Send Email
 
Damn! Accidently I deleted the message with the preliminary 10 min counts
of one of the video cameras operated in California. Will someone be so
kind and forward Juergen (jrendtel@...) and me this message again.

Thanks,
Sirko

--
**************************************************************************
*  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@...     *                          *
**************************************************************************
*  www  : http://www-i6.informatik.rwth-aachen.de/Colleagues/molau       *
**************************************************************************

---------- Forwarded message ----------
Date: Sun, 24 Dec 2000 12:02:23 +0100 (MET)
From: Sirko Molau <molau@...>
Reply-To: meteorobs@...
To: meteorobs@...
Subject: Re: (meteorobs) Ursids active or not - Or unusual stream composition?

Hi Mike,

> I guess we should wait and see what the final report conclusions
> are from everything submitted to IMO for this weird shower.

well said. I fully agree with you!

What I find most surprising is that many European observers saw more or
less increasing activity towards the end of their observing window at 6 UT
(you read the reports of Rainer, Marco and me), whereas most of the
Americans reported only low activity at the given time. The European
increase cannot be due to a raising radiant, since that translates only
into a different digit behind the point in the correction factor.

We have clear enhancements in video data (see my and Peter's report), but
no indication of increased actitivy in reliable radio data like the
Ondrejov backward scatter, which easily picked up recent outburst like the
Draconids. That's all very strange...

A merry Christmas to all of you!
Sirko

--
**************************************************************************
*  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@...     *                          *
**************************************************************************
*  www  : http://www-i6.informatik.rwth-aachen.de/Colleagues/molau       *
**************************************************************************

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#17716 From: peter.atanackov@...
Date: Sun Dec 24, 2000 11:21 am
Subject: (meteorobs) Observation Dec 23/24
peter.atanackov@...
Send Email Send Email
 
Hi!

	 True to the forecast (wow!) the sky remained clear and I could
observe again. I looked for any remaining activity from the Ursids, but
none was seen. There was, however, some activity from the Coma Berenicids.
The sporadics again made up the bulk of activity seen. Rates were
substantially lower than yesterday.
	 The higlight of the night and the only really interesting meteor
was a -5 sporadic fireball at 21:53:50 UT in Leo. It was medium speed,
orange and it  fragmented into 5 pieces midway in its flight. But again
most of the meteors were faint. It planned to stay out until dawn, but the
faint meteors and really low temperatures (-13 C) made me decide
otherwise, so I finished about an hour and a half before dawn.
	 I don't think I want to do another really long session under such
low temperatures anytime soon. True that the sky is usually crystal clear
on such nights, but my fingers and toes are not very keen about it.

The summary:
Period  F teff LM URS COM Spor
16:42-17:42UT 1.05 1.00 6.32 0 - 6
16:42-18:42UT 1.05 1.00 6.33 0 - 8
20:19-21:19UT 1.05 1.00 6.53 0 - 6
21:19-22:19UT 1.05 1.00 6.54 0 0 11
22:36-23:36UT 1.05 1.00 6.53 0 0 17
23:36-00:36UT 1.05 1.00 6.55 0 2 16
00:51-01:51UT 1.05 1.00 6.56 0 3 12
01:51-02:26UT 1.05 0.58 6.53 0 1 17
02:52-03:52UT 1.05 1.00 6.38 0 1 14
			 ----  -------------------
			 8.58  0 7 107

Magnitude distribution:
Spor: -5(1) -1(2.5) 0(2.5) +1(10.5) +2(17.5) +3(31) +4(20.5) +5(16.5)
+6(5)
COM: 0(1) +1(2) +3(2) +4(1.5) +5(0.5)

Merry Christmas to all of you!!

Jure A.

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#17715 From: Sirko Molau <molau@...>
Date: Sun Dec 24, 2000 11:02 am
Subject: Re: (meteorobs) Ursids active or not - Or unusual stream composition?
molau@...
Send Email Send Email
 
Hi Mike,

> I guess we should wait and see what the final report conclusions
> are from everything submitted to IMO for this weird shower.

well said. I fully agree with you!

What I find most surprising is that many European observers saw more or
less increasing activity towards the end of their observing window at 6 UT
(you read the reports of Rainer, Marco and me), whereas most of the
Americans reported only low activity at the given time. The European
increase cannot be due to a raising radiant, since that translates only
into a different digit behind the point in the correction factor.

We have clear enhancements in video data (see my and Peter's report), but
no indication of increased actitivy in reliable radio data like the
Ondrejov backward scatter, which easily picked up recent outburst like the
Draconids. That's all very strange...

A merry Christmas to all of you!
Sirko

--
**************************************************************************
*  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@...     *                          *
**************************************************************************
*  www  : http://www-i6.informatik.rwth-aachen.de/Colleagues/molau       *
**************************************************************************

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#17714 From: Lewis Gramer <dedalus@...>
Date: Sun Dec 24, 2000 9:00 am
Subject: (meteorobs) Weekly IRC Meteor Chat on Monday!
dedalus@...
Send Email Send Email
 
As usual, there will be an Internet Relay Chat (IRC) session
     about meteor observing on Monday evening, starting at 8pm EDT,
     (which is 00:00 UT on Tuesday morning). Anyone with an interest
     in meteors, around the world, is welcome to attend this session
     (or our chat on Saturdays, 11am EDT, 15:00 UT).

     To attend, download a copy of one of the many IRC "client
     programs" (a good one for Windows is called "mIRC", and one for
     the Mac is "IRCle": both are available as try-to-buy shareware
     on the Internet). Once you have an IRC client on your computer,
     connect to the server on "DALnet" known as: irc.dal.net

     After connecting to irc.dal.net, you'll need to enter the
     IRC command for joining a chat session: /join #meteorobs
     "#meteorobs" is the name of our meteor chat session. Good luck,
     and we look forward to "seeing" you on the "#meteorobs channel"!

     Lew Gramer
     owner-meteorobs@...
     Co-Channel Operator of #meteorobs
     Internet Coordinator, N.A.M.N.
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#17713 From: Peter Jenniskens <pjenniskens@...>
Date: Sun Dec 24, 2000 8:06 am
Subject: (meteorobs) Ursid shower - first results
pjenniskens@...
Send Email Send Email
 
We've analysed the first video tape of our observations in California
and find the following (preliminary) rate of Ursids.

Camera: XX1332 Mullard Gen II intensifier, f1.8 50mm optics. Recorded on Hi-8.
The field of view of this camera is 47 x 35 degrees, aimed at an elevation
of 56 degrees West-North-West. Operated by Peter Jenniskens from
120.0W,+35.9N.

  time (UT)  N urs  N other
5:30-5:40    1    0
5:40-5:50    1    0
5:50-6:00    1    2
6:00-6:10    2    2
6:10-6:20    1    5
6:20-6:30    0    2
6:30-6:40    1    1
6:40-6:50    1    3
6:50-7:00    3    0
7:00-7:10    3    4
7:10-7:20    2    0
7:20-7:30    3    0
7:30-7:40    2    2
7:40-7:50    7    0
7:50-8:00    1    3
8:00-8:10    3    3
8:10-8:20    3    0
8:20-8:30    6    3
8:30-8:40    1    1
8:40-8:50    4    0
8:50-9:00    1    1
9:00-9:10    4    5
9:10-9:20    0    0
9:20-9:30    0    4
9:30-9:40    1    1
9:40-9:50    1    5
9:50-10:00   2    4
10:00-10:10  0    5
10:10-10:20  0    1
10:20-10:30  0    2
10:30-10:40  1    3
10:40-10:50  0    2
10:50-11:00  1    1
11:00-11:10  1    2
11:10-11:20  0    2

These were gathered by Peter Gural from a visual scan of the tapes of
one of our intensified video camera's at Parkfield. 11 more cameras to go.
We also detected at least one Ursid spectrum at 08:24:57 UT, covering the
wavelength range from about 400 to 850 nm, the meteor of which was imaged
from both observing sites. 19 double station Ursids thus far after comparisson
with part of the tapes from an aligned intensified video camera at San Antonio
Lake.

An update of further observations is maintained at:
http://www-space.arc.nasa.gov/~leonid/leonidnews29.html


-Peter
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#17712 From: "Mike Linnolt" <mlinnolt@...>
Date: Sun Dec 24, 2000 2:30 am
Subject: (meteorobs) Ursids active or not - Or unusual stream composition?
mlinnolt@...
Send Email Send Email
 
The visual observations reported here paint a very confusing picture
of the Ursids "peak" around 07:30 UT Dec. 22.

Some observers report enhanced activity:

Peter Jenniskens wrote:
"The Ursid shower did flare up significantly last night between 5 UT
and9:30 UT, with a peak around 7:20±10 UT, close to the predicted
maximum at 7:29 UT."

Marco Langbroek wrote:
"the trends suggest a peak near 7:30 UTC indeed, as predicted by
Peter and Esko, with peak rates (interpolated) probably around
ZHR ~75."

Even one estimate at ZHR=200!

Obs: Peter Gural
UTC           Teff  Lm   Urs  Spo   ZHR(Urs)
08:01-08:10   0.15 6.2   10  2      200±65
Of course, this was just a 9 minute Teff! Periods less than 20 or 30
mins for a lower activity shower may be subject to severe
statistical fluctuation.

ON THE OTHER HAND others reported little activity:

Robert Lunsford wrote:
"Rates were quite low the first two hours and the expected
maximum came and went without much activity."

Dan Taylor reported from Ontario:
>Ursids
>*all times in EST
> 	     Ursids     mag            Lim. Mag.
>8:10-8:35           0  -  5.5
>2:14-2:43           2       3m,4m  6.0
>3:15-3:46           3       3m,5m,5m        6.0
>4:14-4:31           1       5m  6.0

Eric Flescher reported from Kansas:
"...the skies were crisp clear and the weather really cold.
I went out and at 1:38 so a beautiful slow moving fireball (mag -3),
Otherwise saw 2 other sporadic 2 magnitude but no ursids. Since
the storm seemed not to show , I retired 30 minutes later."

In addition, the Czech Ondrejov backscatter radar did not show any
enhanced activity from 06:00 - 09:00 UT.

MY OBSERVATIONS under pretty good conditions (LM 5.6 6.1
6.0) covering the peak period from 05:40 - 08:30 UT also showed
very low rates, well below Sporadic. Even adjusting using my pretty
big correction factors like 7 and 4, my best ZHR only hit 14.3, and
the "peak" hour from 06:50 to 07:52 had only 1 URS which
converts to a 3.8 ZHR! Unfortunately, I quit at 08:30 UT so cannot
confirm the Ursid mini-outburst between 08:00 - 09:00 UT that
Robert Lunsford observed.

I don't know what to conclude from these divergent reports around
the same "peak" time of 07:30 UT on Dec 22? Some observers
saw fairly decent activity, other practically none. I suppose it could
be attributed to statistical variation, but the differences are quite
large for that. Another possibility could be a very "clumpy"
meteoroid stream. Rather than being typically distributed in space
like most others, this Ursid stream may have had locally denser
patches interspersed with relatively sparse areas. This could
explain the large differences in visual rates seen at various
locations. But would it explain the lack of enhancement by
backscatter radar? I don't know enough about the FOV or volume of
space covered by this device to judge if it could distinguish such
variation.

I guess we should wait and see what the final report conclusions
are from everything submitted to IMO for this weird shower.

Merry Xmas and Happy New Years to all!
Mike Linnolt.

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#17711 From: GeoZay@...
Date: Sat Dec 23, 2000 9:18 pm
Subject: Re: (meteorobs) Meteorites and Terminal velocity
GeoZay@...
Send Email Send Email
 
>>   I believe that sonic booms associatied with meteors indicates a
possibility of high rates of speed in the lower atmosphere where heating
can occur, however, it does not reveal how fast a meteor is traveling only
that it's traveling faster than sound. <<

A meteorite will produce a sonic boom if it reaches an altitude of about 30
miles above the earth and traveling faster than sound at that altitude.
Whether you will hear it or not is dependent upon a variety of reasons. The
program on the history channel did mention that Joe Kittenger broke the sound
barrier during his free fall. Over 700 mph was mentioned and  I chose to
simply use this figure instead of saying he broke the sound barrier. By the
time he reached the lower atmosphere of the last 5 miles, his terminal
velocity was a lot slower than 700 mph as would a falling meteorite.

>>The meteor would have to be traveling
several times the speed of sound to generate heating so sonic booms may be
only an indication that a hot meteorite may strike the ground.<<

A sonic boom means it at least reached about 30 miles above the earth...hot
or cold.

  >>In working with iron the red heat of a metal will reappear
after sudden cooling if the interior is red heat hot or more, so exterior
cooling during freefall may not last long enough to cool the interior of the
meteorite if it is hot from solar heating (prior to entering the shadow of
the Earth), heated in the upper atmosphere while approaching the state of
ablation, and heated during the period of 3X supersonic flight if any speed
occurred.<<

If the interior of a meteorite got red hot, wouldn't the crystal structure of
the interior change and show rapid crystallization with smaller crystals?
GeoZay
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#17710 From: GeoZay@...
Date: Sat Dec 23, 2000 9:05 pm
Subject: Re: (meteorobs) Meteorites and Terminal velocity
GeoZay@...
Send Email Send Email
 
me>>......His velocity during the free fall reached over 700 mph before
>reaching the denser part of the atmosphere with a slower terminal velocity.
>His free fall lasted over 4 minutes and 30 seconds. Apparently his fall
>didn't generate enough heat to damage his fragile human body.<<

>>Uh... don't the faster meteorites enter the atmosphere something more like
700 miles per TEN SECONDS (around 30-72 km/sec)?? Quite a bit faster than
700 mph, in any case.<<

Yes, even slow meteoroids enter the atmosphere something  like 700 miles per
ten seconds. But I'm basically talking about football size meteorites that
have begun their free fall segment during the dark flight stage. By the time
they have reached an altitude of about 20 miles above the earth, they would
have slowed down to a speed that would be considered free fall. They would
have a terminal velocity comparable to what Joe Kittenger experienced during
his free fall from his 20 mile jump from a balloon. If the meteorite was
quite a big larger, it would travel even lower into the atmosphere before
reaching a terminal velocity minus all it's cosmic velocity. It's been
estimated that about a 10 ton meteorite would have something about 2000 mph
velocity just before hitting the ground, thus with a small percentage of it's
cosmic velocity intact. The smaller the meteorite after the meteor phase, the
higher up it will be when it starts a free fall phase and reaching terminal
velocities. A small meteorite will have a fairly long free fall to cool off
any excess heat if it were there. However, I can easily see some heat
generated from the free fall process, but nothing of a radical nature.
GeoZay
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#17709 From: Masaaki TAKANASHI <takanashi@...>
Date: Sun Dec 24, 2000 12:46 am
Subject: (meteorobs) Ursids in Japan : visual observation results
takanashi@...
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Ursids 2000 prompt report (Update)
Visual results in Japan (The Nippon Meteor Society).

ZHR has been computed with:
-  gamma = 1.0 (correction of Radiant elevation)
-  r = 3.0  ("IMO Handbook for Visual Observers" P.273)
-  excluding:observations under unfavourable condition
    (T<30m, Lm<4.5mag, Cl>0.4, RP-h<10deg)
-  Err. : ZHR * 1/SQRT(#URS)

Hourly ZHR
----------------------------------------------------------------
Time[UT]    SunL   Obs  T.eff  #URS   ZHR   Err.  (HR)   Remarks
----------------------------------------------------------------
Dec. 2000
21d 12:30  269.959   1   1.25     1     6     6  (  1)
21d 13:30  269.991   1   1.00     2    12     8  (  2)
21d 14:30  270.859   2   1.83     3     6     3  (  2)
21d 15:30  270.901   3   3.00     4     4     2  (  1)
21d 16:30  270.944   2   2.00     3     5     3  (  2)
21d 17:30  270.986   2   2.00     4     7     3  (  2)
21d 18:30  270.028   2   1.50     2     5     3  (  1)

22d 08:30  279.808   4   2.00    13    52    14  (  7)
22d 09:30  270.840   9   7.78    70    52     6  (  9)
22d 10:30  270.882   9   8.22    54    30     4  (  7)
22d 11:30  279.925   6   6.00    45    29     4  (  8)
22d 12:30  270.960   4   2.83    15    20     5  (  5)
22d 13:30  271.010   2   2.00    12     9     3  (  6)
22d 14:30  271.052   8   7.75    20    15     3  (  3)
22d 15:30  271.095   4   4.00     8     2     1  (  2)
22d 16:30  271.137   3   3.00    12     6     2  (  4)
22d 17:30  271.180   2   2.00     8     3     1  (  4)
22d 18:30  271.222   2   1.50    10     6     2  (  7)
22d 19:30  271.264   3   3.00    11     4     1  (  4)
22d 20:30  271.307   3   2.67    11     6     2  (  4)
----------------------------------------------------------------

Observers (20members) :
Seiji AKAGI, Daiyu ITO, Hiroyuki KATO, Noriko KOBAYASHI, Wakaba KOBAYASHI,
Kumiko KOUSAKA, Karimu KURAGAKI, Katsuhiko MAMETA, Yukihisa MATSUMOTO,
Hidekastu MIZOGUCHI, Tetsuya NAKAMURA, Yoshiko NAKAZAWA,
Hiroyuki NISHIMOTO, Kazuhiro OSADA, Mitsue SAKAGUCHI, Satoshi SAKAI,
Mikiya SATO, Tomoko SATO, Yasuo SHIBA, Kazuhiro SUMIE, Yasuhiro TONOMURA

Total observations          :  3,920 min. (= 65.33h)
Total number of URS meteors :    308

See more details showing at :
      http://www.nms.gr.jp/en/index.html
      http://www.nms.gr.jp/nmsnews_e.html
      http://www.nms.gr.jp/urs0001.gif

-----------------------------------------------------------------------
Masaaki Takanashi  (The Nippon Meteor Society / Gotemba city, JAPAN)
                                    E-Mail : takanashi@...
The Nippon Meteor Society's Web page : http://www.nms.gr.jp/en/
  (New URL! Please change your bookmark and linkspot in your Web site.)
-----------------------------------------------------------------------

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#17708 From: Robert Gardner <rendrag@...>
Date: Sun Dec 24, 2000 12:27 am
Subject: Re: (meteorobs) Meteorites and Terminal velocity
rendrag@...
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If you have ever removed both Pyrex and metal containers from the oven you know
how different the temperature of the container feels.  It depends on both the
thermal capacity and conductivity of the material.  I would think there would be
the same thing with the feel of a stony meteorite and a metallic ones and the
other materials between these extremes.

GeoZay@... wrote:

> In a message dated 12/23/00 1:36:17 PM Pacific Standard Time,
> epmajden@... writes:
>
> <<
>  Dr. Peter Millman investigated the Benton, N.B. fall which was picked up
>  immediately after landing and this meteorite was hot.  It was reported to be
>  like a hot potato that you couldn't hold comfortably in your hand but could
>  toss it from one hand to another. <<
>
> About how hot would this be? 120-150 deg F. range maybe? Not an unreasonable
> possibility. Hot enough to not hold comfortably. Any reports of blistered
> skin from this hand tossing?
>
>  >>Other meteorites are cold on landing.
>  Dr. Halliday refered me to a paper with the title, "Temperatures of
>  Meteoroids in Space" by Clay P. Butler from the U.S, Naval Radiological
>  Defence Laboratory in San Francisco, which was published in the Journal,
>  METEORITICS, volume 3, 1966 pages 59-70.  Meteoroids in a near Earth
>  enviroment aren't as cold as one would think.<<
>
> If there was a small accumulation of heat within the meteoroid from solar
> radiation just slightly greater than what drains back into the cold of space,
> wouldn't eventually the meteoroid become so hot that the interior crystal
> structure changes? Has there been any meteorites found with indications of a
> recently remelted and quickly crystalized interior beyond the fusion crust?
>
>    >>  Believe what you like George, but I think I will accept what the
>  professionals say until observational evidence indicates otherwise.
>   >>
>
> That's very courteous of you. But from what I can gather there appears to be
> confusion of what's observational evidence with anecdotal "evidence". Did Dr.
> Millman take any temperature measurements of the Benton, NB fall that would
> support the hot potato-like temperatures or was he going strictly by an
> anecdotal story?
> GeoZay
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