Tunguska Blast Remains a Mystery

Early on the morning of June 30, 1908, a tremendousapproached from a direction with a very small angular
explosion rocked the Tunguska region of Centraldistance from the sun, rendering it invisible. Given an
Siberia. Hundreds of square miles of forest wereearly morning time of impact, the comet would then
completely flattened, a huge fireball rose into thehave approached from the east with the tail
sky, and a large black cloud appeared above thestreaming ahead of the nucleus (away from the sun)
region. A shock wave circled the globe twice, andtowards the west which may account for the
strange, glowing skies ere evident throughout Europeglowing night skies seen over Europe and Western
and Asia for days after the event.Asia after the explosion.
Since the event occurred, several theories relating toThe proponents of the extraterrestrial spacecraft
its origin have been presented. Some feel that thetheory dispute the comet theory for several reasons.
explosion was the result of a meteor impact, whileFirst of all, several eyewitnesses claim to have seen
others feel that a comet was responsible for thethe object approaching from the southwest, veer
devastation. Still others feel that because of thetowards the east, then back toward the west
observed trajectory of the incoming object, it maybefore exploding. Also, the object appeared to slow
have been an extraterrestrial spacecraft of somedown just prior to the blast. The blast pattern itself
type.appeared to be irregular, suggesting that the
Years later, when the first research team finallyexplosion occurred inside some type of restrictive
reached ground zero, they observed no crater, andshell. Other evidence suggests the possibility that the
could not locate any meteor debris, so the meteorblast was nuclear in nature, thus accounting for the
theory was dismissed (by most), and the cometincrease radioactivity levels reported in the region and
theory became popular. A comet, composed mostlyaccelerated plant growth in the years following the
of ice and dust, would explode upon entering theexplosion.
earth's atmosphere, creating an airburst similar to thatAt best, proof of the source of the Tunguska
observed in this case. The conversion of the kineticexplosion is far from definitive. Unfortunately, the
energy of the incoming comet to heat would result inregion is not easily accessible, and is not a pleasant
a blast of tremendous proportions.environment to work in, so it is unlikely that we will
The question is: Why wasn't the comet seen as itever know for sure what precisely happened.
approached the earth? A comet that close to theExpeditions are planned to probe some of the lakes
sun exhibits a glowing nucleus and extensive tail,and bogs near ground zero for meteoric evidence,
making it easily visible to the naked eye. If thebut for now, speculation continues.
object was indeed a comet, it must have