There is a very curious hypothesis about why no one has been able to find the crater of a mysterious guest from space for more than a century.
In the early morning of June 30, 1908, an object landed in Siberia with a monstrous roar. As a result, 2,150 square kilometers of forest (about 80 million trees) turned into piles of charred chips and debris. Eyewitness accounts describe a shining ball that smashed windows and crumbled plaster in houses. Researchers later described this event as a 30 megaton meteor explosion at an altitude of 10 to 15 kilometers.
Although the crater itself was never discovered, the search for fragments of meteorite ore continues to this day. But a large asteroid, composed primarily of iron and entering the Earth's atmosphere at a slight angle and then hiding in space again, could have just had a similar destructive effect without leaving any traces.
“We studied the conditions for the passage of asteroids with a diameter of 200, 100 and 50 meters, consisting of three types of materials - iron, stone and water ice, through the Earth's atmosphere with a minimum trajectory height in the range from 10 to 15 kilometers, - say the authors of this theory and in particular astronomer Daniil Khrennikov from Siberian Federal University. - The results obtained confirmed our idea, explaining one of the long-standing problems of astronomy - the Tunguska phenomenon, which has not yet received reasonable and comprehensive interpretations. We claim that the Tunguska incident was caused by an iron asteroid body that passed through the Earth's atmosphere and returned to circumsolar orbit."
The body of ice, a hypothesis proposed by Russian researchers in the 1970s, was fairly easy to rule out. The heat generated by friction against the atmosphere at this speed would completely melt the ice body even on approach. A rock meteor is also more likely to crumble to pieces due to the increase in pressure when air enters the flying body through microcracks. Only iron meteors are stable enough to maintain their integrity.
That is, the most likely culprit is an iron meteorite 100 to 200 meters across, which flew 3,000 kilometers through the atmosphere. With such characteristics, its speed should have been 7 m / s, and the flight altitude should have been 11 kilometers.
This model explains several characteristics of the Tunguska phenomenon at once. The absence of an impact crater is due to the fact that the meteor simply did not fall to Earth. The lack of iron debris is also due to its high speed, as the object will move too fast and will be too hot to lose matter. The researchers said that any loss in mass could be caused by the sublimation of individual iron atoms, which will look exactly like ordinary earth oxides - so they cannot be extracted from the soil.