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THREE STAGES IN METEORITE RESEARCH
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THREE STAGES IN METEORITE RESEARCH
by D.V.Djomin and V.K.Zhuravlyov
Correspondence to: V.K.Zhuravlyov, Post Box 168, Novosibirsk 630058 Russia.
e-mail: tunguska@locutus.nsu.ru
ABSTRACT In the initial stage (1908 - 1949) of the research on the Tunguska Event the aim seemed
simple: to find fragments of a giant meteorite. The second stage ( 1958 - 1993) was a period of the
complex and many-sided explorations of the catastrophe region, computer processing of data, search of
eyewitness communications, investigations of geophysical archives, and testing the validity of simple
models that might explain the phenomenon. The third stage, in the view of the authors, began in 1994
and is a period of establishing an international data bank and use of system analysis as a key to a
solution of
THE FIRST STAGE of the Tunguska Event research may be considered as the interval between years
1908 and 1949. In 1908 the first letters of eyewitnesses had been received by the Irkutsk Observatory
and had appeared in newspapers. In 1949 a published monograph by Eugene Krinov summarized the
results of Leonid Kulik`s researches ( Krinov, 1949). In this stage, investigators generally accepted the
traditional model: The phenomenon could be explained by a collision of Earth with a minor body of
Solar System, either an asteroid or a comet. The main efforts of scientific investigation were the search
for meteorites.
The event occurred on 30 June 1908, but the search for eyewitnesses and for the site of the explosion
over the taiga did not begin until 1921. In 1927 L. A. Kulik discovered the unique radial pattern of forest
destruction. Its center was identified as the collision site of a presumed giant meteorite with Earth's
surface. An aerial survey was made in 1938. Kulik organized the tasks of future expeditions, including
the creation of trails, construction of small storage buildings, geodedical location markers, and
establishing a grid system through the forest by cutting away trees. During this stage, they made a rough
map of the region and interviewed eyewitnesses.
THE SECOND STAGE may be considered as interval between 1958 and 1993 years (Andreev at al.,
1994, Vasilyev, 1985). The search for fragments of a giant meteorite was repeated, and again the result
was negative. Computer analysis of expedition data had ascertained the altitude and energy of the
explosion over the taiga (6 +- 1 km, 20 - 40 megatons of TNT equivalent). The moment of the explosion
was established precisely, based on geophysical records: 00 h 14.5 +- 0.8 min. of Greenwich time
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