On June 30, 1908, a blast 1,000 times more powerful than the bomb dropped on Hiroshima decimated nearly 2,000 square kilometers of isolated Siberian forest near the Podkamennaya Tunguska River.
Since the explosion that flattened an estimated 80 million trees, theories as to its cause have grown to include UFOs, a black hole that zipping through Earth's surface, a test run of Nikola Tesla’s “death ray” and meteorites. And while the latter has since become the most widely-accepted of the theories, the event mysteriously never left a crater.
Now, more than 100 years after the event, a Russian scientist named Andrei E. Zlobin believes he may have identified fragments of the object that caused the explosion.
First discovered in 1988, the rock-like samples strengthen the argument that, crater or not, the Tunguska explosion was in fact the result of one or more meteorites.
For example, as Zlobin explains in an analysis of his findings, the samples he studied showed evidence of high speed motion as well as intensive expansion of volume during an “explosion-like process.”
In particular, Zlobin sorted through his collection of nearly 100 stones taken from the site to identify three he named “dental crown,” “whale” and “boat,” each of which showed clear evidence not only of melting, but what appear to be regmalypts, the impressions found on the surface of meteorites formed when the hot rock sails through the atmosphere at blistering speeds.
While he has yet to carry out a detailed chemical analysis on the rocks in order to better identify their chemical and isotopic composition, Zlobin notes that the samples’ rusty-brown color may be indicative of a presence of iron, a known component of meteorites.
However, the stony fragments do not necessarily rule out the possibility of a comet given that the nucleus could contain rock particles, Zlobin argues.
Furthermore, the scientist estimates that, based on the evidence, the object responsible for the explosion likely had a density of about 0.6 grams per cubic centimeter, which is similar to that of the nucleus of Halley’s comet.
For this and other reasons, Zlobin believes his findings are, ultimately, “excellent confirmation of cometary origin of the Tunguska impact.”