Meteorites regularly fall on the earth’s surface. An attentive observer can notice fall marks and older objects in the environment. They do not bypass their attention and earth satellites, regularly bombarding their surface. But most of all, the craters left on the Moon and Mars are frightening. Their size and monstrous depth give rise to dreary thoughts about what will happen if a meteorite falls to Earth.
What meteorite is called fallen
As a rule, only parts or tiny fragments of a stone that has ended up on the earth’s surface claim to be a fallen meteorite. This phenomenon occurs under the influence of a thermodynamic load, which is exerted by the dense regions of the earth’s atmosphere.
The whole object explodes or shatters, forming meteor showers that fall on the planet’s surface. If larger objects passed this obstacle without damage, then they leave craters of various sizes, ranging from barely noticeable to giant cavities reaching tens of kilometers.
For example, you can remember June 30, 1908. On this day, a meteorite flew over the taiga, near the Podkamennaya Tunguska River. It exploded in the air, in the vicinity of the Earth. This celestial body left its mark on history under the name of the Tunguska meteorite.
Most small meteorites are scattered at a considerable distance from each other, so they are difficult to find. This phenomenon is called a meteor shower.
Examples of falls of meteorites known to science
For the last 500 years, such serious cosmic bodies have not fallen on the earth’s surface to cause a catastrophe on a global scale. All the damage caused by accidentally falling meteorites can be estimated in several residential buildings and a couple of industrial facilities.
Against their background, meteorites of more ancient eras seem to be especially amazing, leaving behind impressive traces on the surface of the planet:
- South Africa, Vredefort crater, 300 km in diameter;
- Russia, Republic of Sakha-Yakutia, Popigai crater, diameter 100 km;
- Canada, Ontario, Sudbury Crater, 250 km in diameter;
- Canada, Quebec, Manicouagan crater, 100 km in diameter;
- Mexico, Yucatan Peninsula, Chicxulub crater, diameter 170 km.
The most ancient representative of the found celestial bodies is the Huangshitai meteorite, located in China, in the Xi’an province. Scientists at Oxford University have put forward the assumption that this two-ton stone was on the earth’s surface almost 2 billion years ago. A worthy competitor can be made by the heavyweight Goba, who was found in the deserts of Namibia. Its dimensions are amazing – almost 60 tons
The protection of the earth’s atmosphere is practically perfect, so very rarely especially large objects fall on the planet’s surface. But the threat still remains.
All the means of observation that are in the hands of scientists at the moment can only make up an approximate picture of outer space. Yes, recently researchers from the USA, China, Russia, Japan and other countries have created a special system for detecting dangerous space bodies.
But she sees what is happening a little further than the earth’s surface. Everything else is out of sight of technology, which is undoubtedly its weak point. Therefore, the question of what will happen if a meteorite falls on the Earth remains open.
Chelyabinsk meteorite. 18 meters in diameter
According to some scientists, the meteorite that exploded over Chelyabinsk was part of a larger asteroid, in which there was a lot of iron. If there were even more of this iron, then most likely it would not have allowed the asteroid to split in the upper atmosphere and it would have flown to the Earth, causing more significant destruction.
Iron would cause a fairly large crater to form. Now it is difficult to say something, but its diameter, most likely, would be at least several tens of meters, says Campbell-Brown.
If the Chelyabinsk meteorite turned out to be a comet, it would cause serious destruction thanks to its speed alone, says Mark Bailey, a comet expert and head of the Arman Observatory in Northern Ireland.
The asteroid enters the atmosphere at a speed of 42,000 to 90,000 km / h, and comets, in turn, can move at speeds of 251,000 km / h. Energy is a function of the square of the speed, so if you double the speed of an object, you get four times the energy.
Comets, due to their long-period orbit and huge kinetic energy, have every chance of colliding at a very high speed, regardless of the frictional force that may occur when entering the dense layers of the atmosphere.
It follows from all this that they can cause very serious destruction when they collide with the Earth. Perhaps in some cases much more serious than collisions with larger asteroids.
Asteroid 2012 DA14. Diameter 30 meters
The space stone that flew by on February 15 at a distance of 27,500 km from the Earth was almost twice the size of the Chelyabinsk meteorite. If it collided with the Earth, it would cause an explosion equivalent to a 2.4-megaton bomb. By comparison, the atomic bomb dropped on Hiroshima during World War II was equivalent to “only” 17 kilotons. This explosion instantly killed about 70,000 people. They literally evaporated.
Tunguska meteorite. Diameter from 60 to 100 meters
The Tunguska meteorite, or as some call it the Tunguska comet, still causes controversy among many scientists. The bottom line is that in June 1908, in the region of the Podkamennaya Tunguska River. At the same time, the explosion killed 80 million trees located on an area of more than 2,000 square kilometers.
Its blast wave with a power of 10 to 15 megatons was about 1000 higher than that of the bomb explosion over Hiroshima. Scientists are still arguing about what size this cosmic body was.
The object was so bright and its light so intense that it caused the trees to heat up and ignite. But the blast wave was so powerful that it also extinguished the fire, so the fire did not last long, says Brown.
Therefore, if a space body of this size would fall into the ocean, it would most likely become the cause of a supergiant tsunami. And if such a body fell, for example, on some city, then no one and nothing would have survived.
It’s not very pleasant to feel when your clothes are on fire. If the object fell on the city, it would cause a colossal number of victims and massive destruction. Perhaps he would not have destroyed a large city, but with a town like New Orleans, where Hurricane Katrina took place, he could have dealt with it at once.
In addition, asteroids and comets of this size can serve to initiate processes of change at the global level. Although they will not be long. In the hemisphere where the explosion will occur, the sky will glow brightly for several days due to ice particles formed from a sharp temperature drop.