Tunguska—the Fire in the
No one can dispute the occurrence, but
how it happened is the subject of continuing, and often
heated, controversy. Despite the best efforts of science,
every acceptable “explanation” leaves inescapable facts
still shouting for attention.
The event began
at about 7:15 on the morning of June 30, 1908 in a remote
region of central Siberia near the Stony Tunguska River. A
blue-white fireball—brighter than the Sun, some said—raced
across the sky, then exploded with the force of a 10- to 15-
megaton hydrogen bomb.
felled some 60 million trees across an area of 2000 square
kilometers. Yet some trees near the blast center were not
burnt and a ring of burnt trees circling the epicenter was
left standing. The thunderous sounds were accompanied by a
shock wave that knocked people off their feet and broke
windows hundreds of kilometers away.
registered on seismic stations across Europe and Asia, and
as far away as Britain meteorologists registered
fluctuations in atmospheric pressure. The resulting pulse of
air pressure circled the Earth twice, and astronomers
observed for several nights afterwards a glowing red haze in
the upper atmosphere, though they were not aware of the
cause at the time. Curiously, reports of an unusually
bright night sky began the night before the Tunguska
event and continued for several days afterwards.
For the next few
weeks, reports suggest that the night skies were aglow to
such an extent that one could read in their light. Both the
Smithsonian Astrophysical Observatory and the Mount Wilson
Observatory reported a decrease in atmospheric transparency
persisting for several months.
What, then, was
experienced by the witnesses to the event: Accounts
gathered by the Russian mineralogist Leonid Kulik, in his
1930 expedition to the site of the explosion are consistent
enough on many details to be considered generally reliable.
Here is an excerpt from the account of resident Semen
time I was sitting by the house at Vanavara factory facing
North. [...] I suddenly saw that directly to the North, over
Onkoul's Tunguska road, the sky split in two and fire
appeared high and wide over the forest. The split in the sky
grew larger, and the entire Northern side was covered with
fire. At that moment I became so hot that I couldn't bear
it, as if my shirt was on fire; from the northern side,
where the fire was, came strong heat.
“I wanted to
tear off my shirt and throw it down, but then the sky shut
closed, and a strong thump sounded, and I was thrown a few
yards. I lost my senses for a moment, but then my wife ran
out and led me to the house. After that such noise came, as
if rocks were falling or cannons were firing, the earth
shook, and when I was on the ground, I pressed my head down,
fearing rocks would smash it. When the sky opened up, hot
wind raced between the houses, like from cannons, which left
traces in the ground like pathways, and it damaged some
crops. Later we saw that many windows were shattered…”
expedition to the Tunguska explosion site was inspired by
his belief that a gigantic meteorite struck the area and
that the iron recovered could pay for the cost of the
expedition. He received support from the Soviet Academy of
Sciences. The story is curiously similar to
Daniel Barringer’s investigation of Meteor
Crater in Arizona—except that in Kulik’s case neither a
meteor nor an “impact crater” could be found.
However, a later
investigation by mineralogist O. A. Kirova recovered both
magnetite globules and various forms of silicate globules
from samples obtained by Kiril Pavlovich Florensky's
expedition in 1958. Thousands of "tiny brilliant spheres,"
many fused together, were found embedded like pellets in the
earth and in the trees. Globules of this sort are
characteristic of the enigmatic particles produced when
meteoroids enter the atmosphere. (As we shall note in the
submission to follow, the study of such formations leaves
many unanswered questions.) The Tunguska globules occur over
a fairly well-defined ellipse, with high concentrations
between 100 and 200 kilometers to the north-north-west of
the epicenter. Florensky suggested that this distribution
might be explained by fallout downwind of the high-altitude
location of the final explosion.
today envision the cause of the destruction as either a
small comet or asteroid exploding a few miles above the
surface. Some estimates point to an object 100 meters in
diameter. According to the calculations of Christopher Chyba
of the NASA Goddard Space Flight Center in Greenbelt,
Maryland, only a stony meteorite would explode at an
altitude of 10 kilometers, the commonly agreed height of the
Tunguska blast. A comet of the assumed size would
disintegrate much higher in the atmosphere and cause less
damage on the ground.
are still arguing over certain unexplained events and the
fact that no samples of the “impacting” object have ever
been found. "If a group of experts cannot agree for almost a
hundred years, it's probably a third option," says Wolfgang
Kundt, an astrophysicist from the University of Bonn in
Ol'Khovatov, an independent Russian physicist who is
intrigued by the Tunguska event, agrees that the impact
theory leaves too many unanswered questions. He points out,
for example, that witnesses reported strange weather and
increased seismic activity in the area for days
The absence of a
coherent explanation has inspired a host of speculations.
Some exotic theories suggest a miniature black hole passing
through the earth, or a miniature “bomb” of anti-matter.
Alternatively, either an exploding alien spacecraft, or an
alien-produced nuclear bomb has been offered. Some suggest
that it was Tesla testing his “death ray”. As a
light-hearted jest amid the carnival of speculations,
electrical theorists wonder if a “microscopic packet of
neutronium” (the fictional content of “neutron stars”) might
be the next explanation offered.