Welcome Guest!
 Tunguska
 W.Kundt's story about TUNGUSKA 2001 Andrei Ol'khovatov Jan 16, 2002 08:08 PST
Dear David and All,

To inflame David's (and maybe others too) interest in visiting Tunguska,
here is below a story by German astrophysicist Prof. Wolfgang Kundt about
TUNGUSKA 2001 conference and his trip to the Tunguska epicenter. In shortern
form it was published in the November 2001 METEORITE magazine issue, and
here you can read detailed version (pictures are omitted).

Best wishes,
Andrei
=========================================
TUNGUSKA 2001 , CONFERENCE REPORT

The Search for the Evasive 1908 Meteorite continues
by Wolfgang Kundt

Meeting at Moscow and Krasnoyarsk
There is a tradition among Russian scientists to celebrate their 1908
Tunguska catastrophe with biennial twin conferences at Moscow and either
Krasnoyarsk or Tomsk, on or around its day of recurrence, 30 June. This
time, in 2001, our convener of the Moscow session was Andrei Ol'khovatov who
had made sure that among the multiple explanations of the catastrophe -
stony asteroid, icy comet, midi black hole, antimatter, mirror matter,
extra-terrestrials, or formation of a kimberlite - the traditional
meteoritic explanation was not the only one to be discussed.
During the two-day conference at Moscow's MEPh Institute, contributions
started, among others, with an honoring of the late N.V. Vasil'ev, and with
the classic interpretation of the orbit and disintegration of a cosmic body
in the atmosphere of Earth (V.P. Korobeinikov, G.A. Tirskii, D.V. Rudenko).
They then shifted to a new interpretation of the catastrophe by Robert Foot
(Melbourne) and Z.K. Silagadze (Novosibirsk), via the infall of a cosmic
object composed of 'mirror matter', i.e. of hypothetical matter with
opposite symmetry under space reflection (parity) which would interact only
quite weakly with ordinary matter. Does such mirror matter exist in the
Universe? It could explain a number of puzzling facts.
Later during the session, geophysical explanations were likewise
discussed, in particular by A. Ol'khovatov, by myself, by G.G. Kochemasov,
and by I.P. Jerebchenko. Kochemasov stressed the preferred geographic
location of the explosion center, with several radial weakness lines and
faults intersecting near the epicenter of the (catastrophe near the) Stony
Tunguska river whose location is not far from the center of the Siberian
craton, with a lane of dozens of kimberlites straddling the site, and with a
(more global) sectoral structure of Earth's eastern hemisphere likewise
running through it. In further support of Tunguska's preferred location,
Jerebchenko highlighted ringlike structures of magnetic anomalies, Moho
isohypses, river-net patterns, tectonic movements, and kimberlites, of radii
ranging from 50 km through a few 103 km, with the Tunguska site sitting at
its center, at an Asian geomagnetic and heat-flow maximum. She also stressed
similarities to the Easter Island !
geology.
As the Moscow session came to an end, its foreign attendants were guided
by a few of their Russian colleagues, through most hospitable meals with
drinks and lengthy metro and bus rides, to a night plane to Krasnoyarsk
during whose flight the sky never fell really dark. On arrival at the city
outskirts in late morning, it became clear that there was another Tunguska
session getting ready to start; but some of us felt like having a rest
first, including myself. Our group counted nine members: Jens Ergon - a
Swedish TV producer - Elmar Bartlmae - a Munich producer working for Welt
der Wunder - accompanied by two Russian camera men plus Martina - the
interpreter - Lars Franzen - a Swedish experimental scientist - two
escorting Russian colleagues: Boris Rodionov and Viktor Lebedev, and
myself - an astrophysicist from Bonn. A small 4-room apartment had been
subrented for us, newly built in the outskirts of the city, but half of the
party
preferred to move on to a hotel. When they tried to pick me up for the
scientific session, four hours later, I turned out to be locked in, and had
to free myself with the help of some kitchen equipment, guided by handy
communication with the outside world. I then learned that I had missed two
of my scheduled talks, but was given another chance later in the afternoon.
The one-day Krasnoyarsk session was organized similarly to the Moscow
one, and attended, among others, by a number of local school boys in company
of their teacher. I.V. Shalamov (Novosibirsk) argued that the catastrophe
had altogether five centers, a fact that may have been known already to
Leonid Kulik through his aerial photographs in 1938-9. Satellite photographs
shown by Yu.D. Labvin (Krasnoyarsk) demonstrated the preferred location of
the central (cauldron) part of the 1908 treefall area, see Fig.1. During my
own talk, one of the school boys volunteered as an apparently excellent
interpreter (into Russian).
Rushing to the Site
After an evening sightseeing tour of Krasnoyarsk and the Jenissei stream,
our international team was allowed a few hours of sleep before being put on
a propeller airplane to Vanavara, the nearest trading center to the Tunguska
site. Viktor , our young Russian conductor, enjoyed fewer hours of sleep
during that night than we did. Vanavara's roads welcomed us so muddy - due
to the shallow permafrost and some ongoing drizzle - that we forgot all
shopping and/or sightseeing plans and simply waited for the helicopter that
was supposed to fly us the 65 km to Pristan - the spacious wooden lodge some
7 km south of Tunguska's epicenter. Swarms of mosquitos convinced us not to
leave the airport shelter for too long.
Then came 'our' helicopter, and carried not only us and our ample camera
equipment but also our kitchen team plus a bunch of soldiers whose purpose
did not get equally clear. All of us were safely flown across the hilly
taiga, its woods and swamps, rivers and occasional lakes, and dropped on a
clearing in the middle of nowhere.
Where were we? I was too excited to wait for a meal even though many
hours had passed without, and followed the only narrow footpath I could
detect offhand for a couple of hours. It turned out to be the right one
towards the epicenter, pioneered by Kulik some 74 years ago ...
Our two TV teams were short of time, hence I was told that there was only
one day for us left to walk to the epicenter and back, namely the following
day; bad enough. But it became an almost cloudless day, with an
unforgettable 12-hour hike through the young woods and swamps, up and down a
few hills which rise some 100 m above their surroundings. What has caused
havock 93 yr ago to this peaceful, invitingly shaped land of largely
circular architecture, centered on Mt. Stoikovich? In many places, I felt
like hiking through the Eifel mountains, west of Bonn, with their deep,
circular lakes called 'Maare', often side by side of a pasture-like terrain,
of equal size and shape but of swampy surface; cf. Fig.2. The Maare of the
Eifel, some 200 in number, are of volcanic origin. During their formation,
thousands of years ago, dust was blown through large distances, e.g. to
Sweden and to Italy.
What New Evidence has emerged ?
So what could we learn when we hiked through the former cauldron, on Kulik's
trails, in pleasant sunshine? We could still see a few so-called telegraph
poles: standing fir trees that had lost all their branches in a supersonic
blast, like in Hiroshima, after the nuclear explosion. We also passed by a
number of large root stumps without stems and pits, not yet rotten, Fig.3,
catastrophe, whose origin has remained a mystery. They must have been hurled
through dozens of meters at least - like John's stone which weighs 10 t, and
has landed on the slope of Mt. Stoikovich with at least sonic speed.
Mt. Stoikovich sits at the center of the 250-Myr old Kulikovskii crater,
easily recognisable from space, near the intersection of several faultlines.
The chemistry of probes collected by the yearly expeditions has always been
found consistent with earthquakes, or volcanic outgassings. The 1999 Italian
hours. Kimberlites and natural gas reservoirs are being detected in the near
neighbourhood of the treefall area, at distances measuring in 100 km.
('Kimberlites' - called after Kimberley in South Africa - are narrow
volcanic outcrops hardly noticeable at the surface except for a shallow
dome-shaped tuff ring, which are mined mainly for their diamonds).
The 4 bright nights in Europe and western Asia, straddling 30 June 1908,
are reminiscent of the 1883 Krakatoa outburst; they ask for transient
scatterers in the upper atmosphere, above 500 km, at heights which only
methane and hydrogen are light enough to reach in sufficient quantity. Fast
rising natural gas has been repeatedly detected in recent years, in the form
of 'mystery clouds' - by airplane pilots - and indirectly as pockmarks on 6%
of the sea floor1.
So why has the 1908 Tunguska explosion not been a tectonicc event, say,
the formation of a kimberlite? Meteoritic impacts tend to leave debris even
when 10$^5$ times less massive than the Tunguska meteorite would have been;
none has ever been found. Volcanic explosions are known to be some 30 times
more frequent than meteoritic ones, at equal energy. Among the meteoritic
ones, stony asteroids tend to collide with Earth some 30 times more
frequently than comets do. The absence of any remnants in the Tunguska area
points, of course, to the rare event of a cometary impact, which would
evaporate at great height. But no comet has been reported in those years,
other than comet Encke. And besides, a shock wave from an impact that formed
at great height would be unable to create a treefall pattern with five
centers, separated by several kilometers. Moreover, a comet entering at
shallow infall angle - as is often claimed - would create a parallel
treefall pattern, not an almost radi!
al one. Under close scrutiny, t
Comparing with the Sikhote-Aline meteorite (1947), and the Cando blowout
(1994)
On 12 February 1947, at 10.30 local time, an iron meteorite struck the
easternmost edge of Siberia, in the western part of the Sikhote-Aline
mountain range. Eyewitnesses reported a bolide crossing the atmosphere
within $\le$ 5 s, though noises were heard for (10$\pm$5) minutes2. The
bolide left a gigantic trail, or smoke band which got increasingly wiggly
but disappeared only towards the evening. According to eyewitnesses, the
bolide split up successively at the four heights of 58, 34, 16, and 6 km,
towards a final diameter of 0.6 km. From infall channels in the ground and
tree destructions, its infall angle could be measured as (30$\pm$8) deg
w.r.t. the vertical.
Within the four succeeding years, over a hundred craters were detected in
that area, the largest of diameter 26.5 m. They formed three concentrations,
spread over an ellipse of diameters 1 and 2 km. All craters were formed by
meteoritic fragments whose impact channels penetrated between 1 and 8 m into
the ground, depending on their shape and orientation. The summed weight of
all the collected iron-rich fragments was 23 t, and estimates yielded about
70 t total for the impacted mass, corresponding to an iron bolide of
diameter 6 m, some 10$^{-3.5}$ in mass of the hypothetical Tunguska bolide.
Even if a comparable amount of rocky material had been left behind in the
atmosphere, in the shape of the dust trail, the Sikhote-Aline meteorite was
still some 1000 times lighter than Tunguska's hypothesized one.
No impactites were found at Sikhote-Aline: explosions after impact tend
to occur (only) for crater diameters $\ga$100 m. Telegraph poles and
snapped-off tree tops were plentiful. Trees were felled radially around
craters, but only in directly adjacent ringlike domains, of width $\la$30 m.
Some of them took bizarre appearances, see Fig.4.
A quite different destruction of comparable energy was the bolide of 18
January 1994, seen and heard at 7.15 UT in the parish of Cando, NW of
Spain3. It took three months until a newly formed crater was reported, of
size 29 x 13 m, 1.5 m deep, whose former (big) pine trees were hurled
downhill through 50 to 100 m, see Fig.5. An in-between road remained clear
of soil from the ejection, eliminating the possibility of a landslide -
which did, however, occur on the same day 300 m NW of the main crater,
knocking down two pines. No meteoritic debris were recovered; the authors
prefer a high-speed gas-eruption explanation.

How to Discriminate ?
Tunguska, Sikhote-Aline, and Cando are three catastrophical events of the
last century - the first of them some 1000 times more energetic than the two
others - which have found quite different explanations in the literature.
Whereas Krinov spends 129 pages of his 397-page book2 on giant meteorites on
the "Tunguska meteorite", Ol'khovatov prefers a tectonic interpretation4.
Even Sodom and Gomorrah have been recently interpreted as former cities on
the SE bank of the Dead Sea, blown up and/or slid to the bottom of the Sea
by a volcanic eruption. How can we discriminate between the terrestrial and
the extraterrestrial interpretation?
Whereas with the former interpretation you can be rejected from
peer-reviewed journals, even when based on sober and friendly arguments, the
latter interpretation may only apply to a 3% minority of all events.
Eyewitnesses speak of bolides - or fireballs - in all cases, and of barisal
guns lasting for many minutes. Trees are felled, or debranched, or their
tops chopped off, craters are formed, and fires are ignited in all cases.
What differs are the details, of which I listed 19 in my talks at Moscow
and Krasnoyarsk. Volcanic flames in the sky can last for minutes whereas a
meteoritic infall trail flashes only for a few seconds, and is hardly sensed
hot in the faces of eyewitnesses, because of too small an extent in space
and time. A meteoritic trail, unlike volcanic flames, tends to stay visible
for hours. Barisal guns, on the other hand, are heard for comparable times
in both cases by distant eyewitnesses (d$\approx$100 km), because sound
echos from warm layers above the stratosphere take that long. For tree
falls, their pattern matters: how many centers? Telegraph poles require
supersonic shock waves. Craters, if blown from below, can contain tree
stumps, whereas those formed by infall show an impact channel plus debris.
Volcanic outblows can throw trees, or tree stumps, or stones through several
hundred meters, whereas non-explosive infalls (with small craters)
redistribute the impacted soil in!
their immediate surroundings.
There are additional criteria. Volcanic blowouts require pressurized
vertical exhaust pipes from a deep-lying fluid reservoir, which have their
imprints on the local geography, like the Kulikovskii crater shown in Fig.1.
Moreover, when megatons of natural gas - mainly methane - are suddenly
released into the atmosphere, they will rise, burn, and form clouds in the
thermosphere for several days, at heights above 500 km, where they scatter
the sunlight. Such scattered sunlight at night is known as the bright nights
of both Krakatoa (1883) and Tunguska (1908). We live on a tectonically
active planet. Exploring it can be great fun.

References:
1. Kundt, W., Current Science 81, 399-407 (2001).
2. Krinov, E.L., Giant Meteorites, Pergamon, 1966.
3. Docobo, J.A., Spalding, R.E., Ceplecha, Z., Diaz-Fierros, F., Tamazian,
V., Onda, Y., ....Meteoritics & Planetary Sciences 33, 57-64 (1998).
4. Ol'khovatov, A.Yu., internet: www.geocities.com/Cape
Canaveral/Cockpit/3240, 1999.

Biodata: Prof. Wolfgang Kundt has retired from the Institute for
Astrophysics of Bonn University. As a former student of Pascual Jordan, he
started his career in General Relativity, then moved into astrophysics via
cosmology, and more recently has also taken strong interest in geo- and
biophysics.

Figure Captions
Fig. 1: False-colour near-IR satellite photograph of the central
('cauldron') region of the 1908 Tunguska catastrophe, roughly 10 km in
extent, and centered on Mt. Stoikovich. Arrows in the margin continue the
rough flow directions of the rivers Cheko, Kimchu, and Khushma which border
the area in the north and south. The Kimchu river flows through lake Cheko
(in the NW of the map). Mt. Farrington, N-NE from Mt. Stoikovich, allows a
good view of the swamps and surrounding mountain chains. Note the preferred
geometry of the cauldron - even detectable from space - which led Kulik to
speak of the 'Merrill circus' inside an 'amphi theatre'.
Fig. 2: A small pond surrounded by swamps, or peat bogs, encountered along
the footpath to the epicenter. Dozens of such swamps encircle Mt.
Stoikovich, see Fig.1.
Fig. 3: One of the dozens of root stumps still lying in that area today,
with their stem segments pointing away from the epicenter. Their original
sites have not been identified. They pose a problem to the meteoritic
interpretation.
Fig. 4: Krinov's book2 shows this remarkable photograph where the
Sikhote-Aline iron shower has deposited a tree-trunk segment in the crown of
another tree. Some intelligence may be required to convincingly explain how
this master piece of natural acrobacy has been achieved.
Fig. 5: Sketch, by Docobo et al (1998), of the destruction achieved by the
1994 Cando event3. A crater was formed at A, with "closed" low edge at D.
Big trees (H; of diameters 0.6 m, height 13 m) were thrown downhill to
distances between 50 and 100 m. The footpath E remained clear of soil or
trees. Soil was thrown to the places marked F and G.

-----éÓÈÏÄÎÏÅ ÓÏÏÂÝÅÎÉÅ-----
ïÔ: Harder, David A <dhar-@bnl.gov>
ëÏÍÕ: tung-@topica.com <tung-@topica.com>
äÁÔÁ: 16 ÑÎ×ÁÒÑ 2002 Ç. 16:46
ôÅÍÁ: [ Tunguska ] freedom of thought

 Good morning Tunguska aficionados Concerning freedom of thought. Dick cannot give free rein to his intellect, and in the end maybe neither can I. In the USA we tote the banner of freedom, but do we really have the freedom we proclaim that we have, if we cannot take flight on the wings of imagination. Some of the greatest human works have come from those journeys. When we were children we were conditioned to believe, that although there were marvelous examples to the contrary like Tolstoy, the average Russian was dead in their soul, because they had no freedom. They were
told
 what to think and how to think. Dick, do you remember the Rocky and Bullwinkle show. Do you remember Boris Bad Enough and Natasha? Russians were stereotyped as sinister and evil. I wonder what nonsense the Russian children were taught about the Americans? The status quo has been pathogenic to the human spirit in all domains of human experience. Do you remember what Mark Twain had to say about mental conditioning? "When even the brightest mind in our world has been trained up from childhood in a superstition of any kind, it will never be possible for that mind, in its maturity, to examine sincerely, dispassionately, and conscientiously any evidence or any circumstance which shall seem to cast a doubt upon the validity of that superstition. I doubt if I could do it myself." Perhaps I am getting dangerously close to the limit, but I tell you, what
we
 have been conditioned to believe plays a dynamic role in the Tunguska investigation, as it does in many areas of human experience. Dick, it is a shame that you are restrained in your communications. I feel that you have a major contribution to make. Perhaps the spirit will take a shit on your head, and you will know what you must do. Andrei, I don't know yet how I will convince you, but I must find a way. You must accompany me on the journey. You may say: I am not going to trek into the Cauldron that way with some crazy Yankee Doodle; it is too dangerous and would be a most unpleasant experience. If you are not in
good
 physical condition then you had better prepare. In the end the spirit may light a fire under your ass. All the best amigo Daveh   1/16/02 Geophysical interpretation of Tunguska:
http://www.geocities.com/olkhov/tunguska.htm

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