Antarctic hell: how a meteorite exploded in Earth’s atmosphere 430,000 years ago
Group of scientists discovered evidence of the fall of an extraterrestrial object in Antarctica 430 thousand years ago. More precisely, not a complete fall, but its disintegration in the air. It is assumed that it was a rather large asteroid or meteorite.
The proof is found tiny particles of a specific composition. Scientists suggest that an object with a size of 100 to 150 meters fell into the Earth’s atmosphere. But in the end it did not crash on the surface in the mountains Sør Rondaneand exploded right in the air.
Explosion over Antarctica
What happened then? Scientists believe that the “air blast” destroyed the ice shell. The exploded object produced a cloud of superheated gas. It, in turn, appeared due to the evaporation of an asteroid upon entering the atmosphere. Filled with tiny molten particles and hot steam, the cloud moved like a jet at super speeds, according to geochemist and planetary scientist Matthias van Ginneken, a researcher at the University of Kent in the UK. It did not have time to lose momentum after reaching the Antarctic ice sheet. When the jet nevertheless reached the surface, it continued to move at a speed close to several kilometers per second.
Since the object did not hit the surface, the crater did not form either. But the area of contact with a cloud of superheated gas turned into a hellish landscape, the temperature there in a few seconds reached more than 1,000 degrees Celsius. “This means that everything that stands directly in front of the jet of heated gas would evaporate, a huge shock wave was created as a result of the explosion of an asteroid near the Earth. Air explosions are very dangerous, as they occur quite often, ”said van Ginneken.
There are at least two known air explosions in recent history. But both were weaker than recorded in Antarctica.
1. The famous Tunguska event of 1908 is the most striking example, when an exploding asteroid knocked down tens of millions of trees over 2,150 square kilometers of Siberia.
2. Explosion over Chelyabinsk in 2013, then the asteroid frightened the population and broke windows over a vast area.
Found traces of the meteorite
Scientists have tried to find other evidence of the disaster in Antarctica. The search took van Ginneken and his colleagues to the Sør Rondane mountains. The team spent a full day at the top of Mount Walnumfjellet, where they sampled glacial deposits from an ancient and glacier-eroded surface. Returning to the station, they found micrometeorites and unusual-looking particles, similar to several spheres coalesced together at a very high temperature.
In total, they found 17 spherical magma particles. Using microscopes and laser methods, they discovered the minerals olivine and iron spinel in particles ranging in size from 100 to 300 micrometers, fused into small pieces of glass. but chondritic the composition and high content of nickel led them to believe that the particles were alien, which served as an argument in favor of the explosion of a space guest in the Earth’s atmosphere.
There is no doubt that a detailed study of this region of Antarctica will reveal many more surprises.
To determine when the particles appeared, the team compared them with others previously found in EPICA ice cores (European Project for Ice Coring in Antarctica) Concordia domes and Fuji domes… A large meteorite invasion was also recorded there, and remnants of meteorite dust and other particles were found. These particles belong to the same time period, most likely, they were formed as a result of the same event about 430 thousand years ago.
Is it possible to protect the planet from the invasion of meteorites?
In a number of countries, monitoring systems have been created that track the trajectory of the fall of celestial bodies invading the Earth’s atmosphere. In Russia, fireball networks are poorly developed, the first of which is relatively recent established Ural scientists.
The results of the observations make it possible to determine the velocity, trajectory and geometry of the scattering field of extraterrestrial matter by the method of celestial mechanics and bolide physics. To prevent a catastrophe, a celestial object that threatens the safety of populated areas should be identified in a timely manner and appropriate measures should be taken.
What do we know about Antarctica
Antarctica remains a poorly explored continent to this day. Ancient geographers predicted the existence of this land 2 thousand years before its discovery. An expedition led by James Cook first crossed the Antarctic Circle in 1773, but never found the mainland.
In 1820, a Russian round-the-world naval expedition led by Thaddeus Bellingshausen and Mikhail Lazarev was finally convinced of the existence of the southern continent.
In 1959, twelve states, including Argentina, Australia, USSR, USA, Japan, signed the International Treaty on Antarctica. The treaty prohibits the use of the continent for military purposes, provides for freedom of scientific research and the exchange of information on the results of the work of research stations and expeditions. Until now, the treaty is respected and this place is called “the continent of science and peace.”
Antarctica is one of the most mysterious continents. Revealed secrets raise many new questions for polar explorers and modern scientists, and most of the mysteries we have yet to solve.