What is the depth of the earth’s core?

It is commonly believed that the Earth’s core lies at a depth ranging from 6,000 to 6,400 kilometers beneath the Earth’s crust. The core, which constitutes the innermost part of the Earth, is composed of iron, nickel, and sulfur.

The Earth’s crust, on the other hand, forms the outer layer of the planet and primarily consists of rocks and sediments.

The core of the Earth, known as the inner core, is located at the center and deepest point of the planet. It is incredibly hot, with temperatures exceeding 5000°С. It is interesting to note that despite the extreme heat, the pressures at this depth are so intense that they keep the core in a solid state.

The Earth’s Layers

The Earth is composed of three major layers, each with its own unique characteristics. The outermost layer is the lightest and consists of elements such as oxygen, magnesium, calcium, and others. The middle layer is much denser and is made up of iron and nickel, making it the heaviest and thickest layer.

– The Earth’s Crust

The Earth’s crust is the outermost layer of the Earth’s surface and is the lightest. It has a thickness that ranges from 5 to 80 kilometers. The Earth’s crust is primarily composed of various types of rocks. Additionally, the Earth’s crust is divided into two distinct levels:

The Continental Divide

The Continental Divide is the uppermost layer of the Earth’s crust and is primarily composed of continents. Its surface is composed of volcanic rocks, such as granite. This layer has a depth of approximately 35 to 40 kilometers.

The average thickness of the oceanic crust, which is formed by the bottom of the oceans, is around 6 to 7 kilometers. It primarily consists of volcanic deposits such as basalt and gabbro.

Located in the western Pacific Ocean, the deepest point in the Earth’s oceans is an oceanic trench known as the Mariana Trench. This trench, specifically called the Guam Trench, reaches a depth of 11,035 meters, making it the closest point to the center of the Earth that mankind has not yet been able to reach.

– The Earth’s Mantle

The Earth’s mantle is located between the crust and the core, and it has an approximate thickness of 2,900 kilometers surrounding the core.

Composed mainly of silica, magnesium, and oxygen, the mantle is primarily comprised of rocks known as peridotites. This layer accounts for about 82% of the Earth’s volume and 68% of its mass.

The mantle plays a crucial role as its temperature and pressure create the necessary conditions for minerals to remain near their melting point. It is within this environment that materials resulting from volcanic eruptions are formed.

– nucleus

This is the innermost section of the Earth and can be found at its center. It measures approximately 7000 kilometers in diameter.

The nucleus is comprised of two segments:

The outer nucleus

It exists in a fluid form as it lacks sufficient pressure and maintains a temperature of around 4000 ° C, preventing it from solidifying.

Through its movements in the liquid state, the nucleus facilitates the presence of the Earth’s magnetic field.

The Core of the Earth

The inner core of the Earth is in a solid state due to the immense pressures it experiences, which restrict any movement.

Both the inner and outer cores are composed of iron and nickel. However, the different levels of pressure and temperature are crucial factors in determining the state of each core.

1. Aguilar, H. S. (2002). Nature and society: an introduction to geography. Peru: PUCP Editorial Foundation.
2. Luis, M., A. V. (2005). From creation to the shape and structure of the Earth. Mexico: UNAM.
3. Reckzigel, M., W. S. (2000). Great Haack pocket atlas. AKAL Editions, 2000.
4. Karenas Fernandez, M. B., J. L. (2014). Geology. Madrid, Spain: Ediciones Paraninfo, S.A.
5. Valdivia, L. M. (1996). Geophysical properties of the earth. Mexico: Luis M. Alva Valdivia.

Within the Earth’s center, there are two distinct layers separated by a boundary region: the external liquid core layer measures approximately 2266 kilometers in thickness, while beneath it lies a colossal, compact core with an estimated diameter of 1300 km. The transitional area possesses an irregular thickness and gradually solidifies as it transforms into the inner core. Near the surface of the uppermost layer, the temperature hovers around 5960 degrees Celsius, although this information is deemed as an approximation.

Approximate composition of the outer core and methods of determining it

There is still limited knowledge about the composition of the Earth’s outer core, as it is impossible to collect samples for analysis. Iron and nickel are believed to be the primary components of the outer core based on the analysis of meteorite composition. Meteorites, which are fragments from asteroids and other planets, provide insights into the composition of the Earth’s core.

However, meteorites cannot be deemed to possess identical chemical compositions, since the original celestial bodies were significantly smaller in size compared to Earth. Following extensive investigation, scientists have reached the conclusion that the liquid portion of the nuclear material is significantly diluted with various other elements, including sulfur. This accounts for its lower density in contrast to iron-nickel alloys.

The boundary between the core and the mantle in the Earth’s interior is characterized by a non-uniform outer surface. It is believed that this region exhibits a unique internal topography, which is a result of the continuous mixing of diverse materials from deep within the Earth. These materials differ in their chemical composition and density, leading to variations in the thickness of the core-mantle boundary, which can range from 150 to 350 kilometers.

Previous authors of fiction have depicted an expedition to the heart of the Earth by traversing through extensive caverns and subterranean passageways. Can such a venture truly be accomplished? Unfortunately, the immense pressure at the core’s surface surpasses 113 million atmospheres. Consequently, any cavern would have forcefully sealed shut as we neared the mantle. This clarifies the absence of any caves on Earth that extend beyond a minimum depth of 1 kilometer.

What methods are used to investigate the outer layer of the core?

By monitoring seismic activity, scientists are able to infer the composition and structure of the core. One intriguing finding is the differential rotation of the inner and outer layers, influenced by the magnetic field. The core of the Earth remains a treasure trove of unanswered questions, eagerly awaiting breakthrough discoveries.

Research into the composition of the Earth’s material started when geophysical methods, such as seismological research, were developed. Seismology focuses on studying the variations in the speed of elastic vibrations or seismic waves as they travel through different types of structures. It has been understood for a long time that sound waves travel much faster through dense materials compared to air. This is why if you put your ear to the ground, you can hear the galloping of a horse much earlier. Seismic waves exhibit the same characteristic.

According to the findings of Croatian scientist Andrej Mohorovicic, it has been observed that seismic waves experience a significant change in their propagation speed at a depth of approximately 50 km. This phenomenon has also been documented by other seismologists in various regions across the globe. Subsequent analysis of the collected data led to the conclusion that the Earth possesses a heterogeneous structure, with a distinct boundary between its crust and mantle at a depth of 50-55 km. This boundary is commonly referred to as the Mohorovičić boundary.

Nonetheless, waiting for earthquakes resulting from different types of cataclysms and wars to occur in order to carry out research on the deep interior was inconvenient. As a result, scientists eventually started to artificially generate elastic vibrations that would “travel” through the earth. The propagation limit of seismic waves was virtually non-existent, allowing for indirect insights into the intricate structure of our planet. After passing through the Earth’s layers and experiencing changes in its propagation speed, the elastic wave returns to the observation point and is detected by an extremely sensitive seismograph.

Since the experimental opportunity of seismic waves “passing” through the Earth was found, numerous similar studies have emerged worldwide. Five years after the discovery of “Mohi”, an American geophysicist named Beno Gutenberg made a new finding: an increase in the speed of seismic wave propagation at a depth of 2900 km. This new discovery indicates the presence of a substance with a density much lower than that of the mantle in the Earth’s center, where immense pressure exists.

Furthermore, at this level, transverse waves (a type of waves that involve oscillations of particles in the medium perpendicular to the direction of the wave’s propagation) were completely attenuated, which typically occurs only when oscillations propagate in a liquid. This astounding discovery confirms the existence of a liquid core within the Earth’s thickness!

Further investigation revealed that the core itself possesses a heterogeneous structure due to the presence of certain longitudinal waves. These waves, which propagate more rapidly and are not dampened by the liquid, are characterized by particles of the medium oscillating in the same direction as the wave itself. However, upon passing through the core, the direction of these waves changes and their speed increases.

It took 15 years for a convincing explanation of this initially paradoxical phenomenon to emerge. Danish seismologist Inga Lehman proposed that the liquid core actually contains an additional solid core, which has a much higher density compared to the mantle. The portion of the waves that “crosses” this inner solid core logically experiences an increase in speed and deflection.

This is a visual representation illustrating the internal composition of our planet

Further investigations in the field of geophysics have revealed that the core exhibits an unusually high level of electrical conductivity, suggesting that it may exist in a metallized or plasma state. What exactly is the chemical makeup of the Earth’s core? Many scientists, dating back to the time of Newton, have posited that the core is composed of at least 50% iron.

The foundation for this hypothesis stems from the calculations conducted by geochemists, which indicate that one-third of the Earth is comprised of iron, while the density of the Earth’s crust is only half that of the entire planet. Therefore, the core could potentially account for the shortage in the calculations. Additionally, celestial bodies discovered by scientists have predominantly exhibited an “iron-like” structure, with the percentage of iron content increasing as the depth of the rock formations escalates.

Until approximately the 1960s, there was no scientific dispute regarding Newton’s assumption, except for the uncertainty surrounding the composition of the “impurities” in the core. Researchers claimed that the nickel found in the meteorite material contributed to a significantly higher density of the core than what seismologists had initially calculated. It was more plausible that a lighter element, such as sulfur or silicon, was present, but there was no means to confirm this hypothesis.

In 1963, the Institute of High Pressure Physics of the USSR Academy of Sciences successfully produced artificially dense quartz. The density of this quartz was twice the normal density. The crystal structure of this mineral differed from regular quartz as the silicon atom was surrounded by six oxygen atoms instead of the usual four. This remarkable mineral was created under a pressure of 145 thousand tons per square inch, which is equivalent to the pressure found at significant depths in the Earth’s mantle. Therefore, it is possible that under the influence of extreme pressures and temperatures, minerals composed of compacted silicon oxide could form within the Earth’s mantle, which is predominantly composed of silicate rocks.

Therefore, the concept arose that the core of the Earth is a conglomeration of silicates that have been transformed into metal through compression. However, this arrangement negated the potential for the mantle material to circulate throughout the entire depth of the planet and, as a result, prevented the emergence of magma on the surface, the movement of continents, and similar phenomena.

The validity of this assumption has been confirmed through theoretical reasoning. Compacted oxides are formed in the Earth’s interior, with these oxides, especially those containing iron, melting at the lower boundary of the mantle to create a liquid outer core with a density that has been experimentally determined.

As electrons rearrange in electron orbitals and higher density oxides appear, free oxygen is released. This oxygen then rises to the surface and encounters iron atoms, descending to the outer core as newly formed oxides. During these migrations, the chemical activity of iron undergoes changes, and at the pressures and temperatures of the inner core, it stops reacting with oxygen, resulting in its release in a pure form.

Such a theory provides a compelling explanation for the presence of a liquid outer core and a solid inner core at the center of the Earth. However, currently, the scientific community lacks the ability to definitively prove or disprove the existing theories regarding the deep interior structure of the planet.

Further Reading

Chapter 1: The Two Lands

Chapter 1: The Two Lands tells the story of King Meneses1. JEB-HUNTER. On a clear summer morning in 5263 B.C., he stood atop a rocky ledge overlooking the Nile valley. Despite his small stature of five and a half feet (165 centimeters) and his dark complexion, he possessed a strong presence.

“Beware the power of the earth!

“Beware the power of the earth! A timeless Latin proverb states, “Navigators fear the land in a tempest.” This proverb still holds true in modern times, even though the treacherous areas for navigation around the world are now marked by countless coastal and floating lighthouses.”

Sannikov’s Three Lands

Sannikov’s Three Lands The initial territory. Sannikov traversed the island of New Siberia from the southern to the northern part using a dogsled, as per Gedenstorm’s instructions. As he ascended the steep incline of the northern coastline, he caught sight of the distinct blue hue that often appears over the distant lands in the Arctic Ocean.

During the aforementioned period, the various ethnic groups residing in the North Caucasus region had a substantial portion of their territory under the control of feudal lords. This land, primarily located in the plains, consisted mostly of arable land and, to a lesser extent, winter pastures. In the 1840s, feudal lords possessed over half of the 660 thousand dessiatinas of land in Kabarda.

Treasures of Scandinavia

Exploring the history and culture of Scandinavia, researchers have been blessed with a plethora of archaeological artifacts, thanks to the era of Germanic tribe resettlement. Among all the countries in the region, Sweden stands out for its abundance of treasures. From the 5th century onwards, gold started pouring into the northern lands, a direct result of the thriving

The stronghold of the planet

I possess “The Handbook of the Russian Farmer, or Manual for the Yearly Cycle of Peasant Labor”, initially printed in 1913. This is not a textbook, but rather a guidebook, lacking numerous particulars as it is tailored for the peasant who is already familiar with these specifics.

“Azure Lands” became a turning point in Tsvetaeva’s destiny, serving as both a catalyst for her professional identity and a catalyst for self-revelation. This revolution stripped her of a sense of connection with the world and redirected all her creative energy towards the construction of an entirely new reality.

Experiencing the Earth’s Circumnavigation for the First Time

During his initial endeavor around the Earth, Fernand Magellanic (Magellan) faced relentless and challenging opposition from Fate. However, there was one instance where Fate smiled upon him: he successfully led an expedition that brought him fame, albeit at the cost of his own life. As a foreigner in his own land, he had

EXPLORING THE WORLD BY AIR

Yevgeny Konoplev Our humble aircraft An-12, which departed from Kiev Mechanical Plant’s airfield two days ago and has now touched down at Yelizovo Airport in Petropavlovsk-Kamchatsky, went unnoticed amidst the bustling activity at the airfield.

THE DISPLACED LANDOWNERS

In the past, the Todas were the rightful owners of the land. They possessed the vast expanse of the Blue Mountain region, including its lush forests and fertile pastures. The Toda community’s claim to the land was based on the duration of their ownership. The exact arrival of shepherds to Nilgiri remains unknown, but it is a well-established fact among the tribes of the Blue Mountains.

Earth Day In 1951, the Paley Commission, established by President Harry Truman to investigate the causes of scarcities of raw materials during the Korean War, highlighted potential future oil shortages and reliance on oil from the Middle East. “The direct utilization of solar energy,

Light from beneath the earth

Light from beneath the ground At night, when you pass by it, you can observe it shining inside like alcohol burning with a bluish flame. It is the witch’s jelly from the cellars exhaling. A. and B. Strugatsky’s “Picnic on the Side of the Road.” 1 It appears that the anxiety before the expedition is an essential part of the mission.

The core of the Earth is the innermost and deepest part of our planet. It is located beneath the Earth’s mantle and is believed to be primarily made up of an iron-nickel alloy with traces of other siderophile elements. The core is situated at a depth of approximately 2900 km, with an average radius of about 3500 km. It is divided into two main parts: a solid inner core, which has a radius of around 1300 km, and a liquid outer core with a thickness of about 2200 km. Sometimes, a transition zone is identified between these two regions [1]. The temperature at the surface of the solid core is estimated to reach around 6230±500 K (5960±500 °C) [2] [3]. The density at the center of the core could be around 12.5 t/m³, and the pressure may reach up to 361 GPa (3.7 million atm). The mass of the Earth’s core is approximately 1.932×10²⁴ kg.

Very little is known about the Earth’s core – all information is obtained through indirect geophysical or geochemical methods. There are no available samples of the core matter.

History of research

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One of the earliest proponents of the concept of a denser region within the Earth was Henry Cavendish, who calculated the mass and average density of the Earth and discovered that it was significantly greater than the density of rocks found on the Earth’s surface.

The existence of the core was first proven in 1897 by E. Wichert, a seismologist from Germany. In 1910, the depth of the core, which is 2900 km, was determined by B. Gutenberg, a geophysicist from America.

In 1922, V. M. Goldschmidt, the founder of geochemistry, suggested that the core was formed through the gravitational differentiation of the primary Earth during its growth or at a later stage.

An alternative hypothesis regarding the origin of the iron core in the protoplanetary cloud was developed by A. Eiken, a German scientist, E. Orovan, an American scientist, and A. P. Vinogradov, a Soviet scientist, during the 1960s-70s.

Back in 1941, Kuhn and Ritman proposed a theory that the Earth’s core is made up of metallic hydrogen, based on the idea that the composition of the Sun and the Earth are identical. They also calculated the phase transition in hydrogen to support their hypothesis. However, this hypothesis has not yet been tested through experiments. Shock compression experiments have shown that the density of metallic hydrogen is significantly lower than the density of the core. Nevertheless, this hypothesis has been adapted to explain the structure of giant planets like Jupiter and Saturn. It was previously believed that the magnetic field of these planets is generated by the metallic hydrogen core.

Moreover, V. N. Lodochnikov and U. Ramsay proposed that the chemical composition of the lower mantle and core are identical – at the core-mantle boundary at 1.36 Mbar, mantle silicates undergo a transformation into a liquid metallic phase (metallized silicate core). C:Wikipedia:Articles without sources (type: not stated) [source not stated 3503 days]

In 2015, it was revealed that there exists a third layer within the liquid part of the core. Through the analysis of seismic waves, a team of geologists led by Professor Xiaodong Song from the University of Illinois concluded that the Earth’s core is not two-layered, but rather three-layered [7] [8] [9].

Composition of the Earth’s Core

The exact composition of the Earth’s core remains uncertain, but scientists have made estimations based on various sources. One possible source of information is iron meteorites, which are fragments of asteroids and protoplanets’ cores. However, it should be noted that the iron meteorites may not be identical to the materials found in the Earth’s core due to differences in size and the resulting variations in physical and chemical conditions during formation.

Alternatively, seismic investigations provide precise measurements of the core’s dimensions [10], while gravimetry data reveals its density. This information places further limitations on the core’s composition. As the core’s density is approximately 5-10% lower than that of iron-nickel alloys, it is hypothesized that the Earth’s core contains a higher proportion of lighter elements compared to iron meteorites [10]. Potential candidates include sulfur, oxygen, silicon, carbon, phosphorus, and hydrogen [10].

Ultimately, the core’s makeup can be approximated based on geochemical and cosmochemical factors. By determining the initial composition of the Earth and analyzing the distribution of elements in other geospheres, it is possible to estimate the composition of the core. Conducting high-temperature and high-pressure experiments that examine how elements are distributed between molten iron and silicate phases greatly aids in these calculations.

In April 2015, a theory was put forward by scientists at Oxford University suggesting that the uranium levels in the Earth’s core are actually slightly higher than what was previously believed [11]. This statement caused a flurry of attention from the media, with many high-profile reports speculating about the possible existence of an uranium core within the Earth [12].

The Formation of Earth’s Magnetic Field

The magnetic field of the Earth is generated by the internal structures of the planet. It is a common misconception that the field is produced by ferromagnetic materials in the inner core, acting as a permanent magnet. However, it should be noted that the ferromagnetic properties of iron are lost above the Curie point temperature. The prevailing hypothesis for the creation of Earth’s magnetic field is known as the Geodynamo theory. According to this theory, the movement of electrically conducting fluid in the outer core leads to the generation of the magnetic field.

Creating a Model of the Earth’s Core

By utilizing data gathered over an extensive period of time from low-orbit satellites, the Earth’s gravitational field can be analyzed. This analysis, in conjunction with quaternion calculus, can provide valuable insights into the structure of the Earth’s core. The information obtained from these observations, which has been lacking a source for 2562 days, can shed light on the composition and characteristics of the core.

It can be viewed as a combined force generated by numerous point masses of varying “mass” positioned in close proximity to the Earth’s center in a specific arrangement. The main objective of these observations is to accurately simulate the actual gravitational field of the Earth during the trajectory of a missile’s flight and provide guidance in space during the stage of separation and deployment of warheads. The success of this model paved the way for the development of maneuverable components for strategic missiles.

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Additional information

1. ↑ D. Y. Pushcharovsky, Y. M. Pushcharovsky (MSU), [www.mparlament.eduhmao.ru/var/db/files/3469.9811_111.pdf Analysis of the Earth’s Mantle] // Soros Educational Journal No. 11 1998
2. ↑ (April 26, 2013) “[www.sciencemag.org/content/340/6131/464 Melting of Iron at the Boundary of the Earth’s Inner Core as Detected by Fast X-ray Diffraction]”. Science Magazine340 (6131): 464-466. DOI:10.1126/science.1233514.
3. ↑ [www.esrf.eu/news/general/Earth-Centre-Hotter/ The Earth’s Core is Actually 1000 Degrees Hotter than Previously Estimated] // European Synchrotron Radiation Facility, April 25, 2013;
   in brief, [lenta.ru/news/2013/04/26/hotter/ Physicists Determine Earth’s Core Temperature] // Lenta.ru, April 26, 2013: “Scientists have recently discovered that the temperature of the solid iron core of the Earth is approximately 6,000 degrees Celsius. This finding revises previous estimates by raising the core’s temperature by a thousand degrees.”
4. ↑ Kuskov, O. L., Khitarov, N. I. (1982) "Thermodynamics and Geochemistry of the Earth's Core and Mantle. M.: Nauka, 1982" p 127: "During the mid-20th century, there were theories suggesting that the Earth’s core could be composed of materials other than iron. Scientists W. Kuhn and A. Rittmann [513] proposed the idea of a core made up of metallic hydrogen, based on their hypothesis that the compositions of the Sun and the Earth are the same and on calculations of phase transitions in hydrogen [666]."
5. ↑ Kuhn W, Rittmann A. “On the State of the Earth’s Interior and its Formation from a Homogeneous Primordial State” – Geological Journal, 1941, vol. 32, issue 3, p. 215-256. doi:10.1007/BF01799758, ISSN 0016-7835
6. ↑ Geologists have recently discovered that the Earth’s core is similar to a three-layer “matryoshka doll” [ria.ru/science/20150209/1046746988.html]. This finding was reported by RIA Novosti – Science on February 9, 2015.
7. ↑ According to a news article from VSEGEI on February 17, 2015, the inner core of the Earth has a complex structure and contains another core [www.vsegei.ru/ru/news/index.php?ELEMENT_ID=96656]. This information was last checked on May 14, 2015.
8. ↑ A study published in Nature Geoscience on February 9, 2015, by Tao Wang, Xiaodong Song, and Han H. Xia, discusses the equatorial anisotropy in the inner part of Earth’s inner core [www.nature.com/ngeo/journal/v8/n3/full/ngeo2354.html]. The study used autocorrelation of earthquake coda to analyze this phenomenon.
9. ↑ 123 In a 2007 publication titled “Formation of Earth’s Core” [es.ucsc.edu/~fnimmo/website/treatise3.pdf], the process of how the Earth’s core was formed is explained.
10. ↑ [www.nature.com/nature/journal/v520/n7547/full/520299a.html Experimental findings propose that if the Earth initially grew by the accumulation of highly chemically reduced material, its core may contain sufficient uranium to sustain the planet’s magnetic field throughout its entire history.]
11. ↑ [www.rosbalt.ru/style/2015/04/19/1390267.html Scientists from the University of Oxford have put forward a theory suggesting that the Earth’s core is composed of radioactive uranium.]
12. ↑ www.earthlearningidea.com/PDF/147_Core.pdf page 2, «There is a widely-held misconception that one piece of evidence for the core being made of nickel-iron is their magnetic properties, which contribute to the Earth’s magnetic field.»
13. ↑ [hyperphysics.phy-astr.gsu.edu/hbase/magnetic/magearth.html Magnetic Field of the Earth]
14. ↑ The geodynamo // EPS 122: lecture 7

Literature

• Petrographic Dictionary, V. Ryka, A. Malishevskaya, M: “Nedra”, 1989
• Allegre, C.J., Poirier, J.P., Humler, E. and Hofmann, A.W. (1995). The Chemical-Composition of the Earth. Earth and Planetary Science Letters 134(3-4): 515—526. doi: 10.1016/0012-821X(95)00123-T.
• Treatise on Geochemistry, 2003, Volume 2 The Mantle and Core:
• Partition Coefficients at High Pressure and Temperature K. Righter and M. J. Drake
• Experimental Constraints on Core Composition J. Li
• Compositional Model for the Earth’s Core W. F. Mc Donough., 2003
• www.popmech.ru/weapon/237452-mezhkontinentalnaya-ballisticheskaya-raketa-kak-eto-rabotaet/ Nikolai Tsygikalo. Space Bus. Popular Mechanics APRIL 2016 (No. 2). [non-authoritative source? 2562 days.]

References

• [vivovoco.astronet.ru/VV/JOURNAL/NATURE/01_02/GEODYN.HTM V. E. Khain, Modern geodynamics: achievements and problems]
• [www.mantleplumes.org/Os-W.html Anders Scherstén, Re-Os, Pt-Os and Hf-W isotopes and tracing the core in mantle melts]
• [www.mk.ru/science/2016/09/09/uchenye-zafiksirovali-peremeshhenie-yadra-zemli.html Scientists have detected the movement of the Earth’s core].

A brief description of the Earth’s core

What is the significance of these criticisms?
Do not the very actions that historians praise Alexander I for, such as the liberal beginnings of his reign, his fight against Napoleon, the firmness he demonstrated in the 12th year, and the campaign of the 13th year, come from the same sources – the factors of blood, upbringing, and life that shaped Alexander’s personality – from which also come the actions for which historians criticize him, such as the Holy Alliance, the restoration of Poland, and the conservative policies of the twenties?
What is the essence of these criticisms?
The essence is that a historical figure like Alexander I, a person who stood at the highest level of human power, exposed to the strongest influences of intrigue, deception, flattery, and self-indulgence that inevitably come with power; a person who felt responsible for everything happening in Europe at every moment of his life; a person who, like anyone else, had personal habits, passions, and aspirations for goodness, beauty, and truth – this person, fifty years ago, was not lacking in virtue (historians do not criticize him for this), but he did not have the same views on the well-being of humanity as a professor engaged in science, reading books and giving lectures, has today.
But even if we assume that fifty years ago Alexander I was mistaken in his views on the well-being of nations, we must also assume that the historian who judges him today will, in time, be unjust in his own views on the well-being of humanity. This assumption is even more natural and necessary because, as history progresses, we see that with each passing year and with each new writer, the understanding of what is good for humanity changes. What seemed good ten years ago may now be considered evil, and vice versa. Moreover, in history, we find completely opposite views on what was considered evil and what was considered good: some praise the constitution and the Holy Alliance given to Poland, while others criticize Alexander.
We cannot definitively say whether Alexander’s and Napoleon’s actions were useful or harmful, because we do not know what they were useful for and what they were harmful for. If someone dislikes these actions, it is only because they do not align with their limited understanding of what is good. Whether it is the preservation of my father’s house in Moscow in the 12th year, the glory of the Russian troops, the prosperity of St. Petersburg and other universities, the freedom of Poland, the might of Russia, the balance of Europe, or a certain form of European enlightenment – progress, I must admit that the actions of any historical figure had aims beyond these, aims that are more general and inaccessible to me.
But let us suppose that so-called science has the ability to reconcile all contradictions and establish an unchanging measure of good and bad for historical figures and events.
Let us suppose that Alexander could have acted differently. Let us suppose that, at the direction of those who accuse him and claim to possess knowledge of the ultimate goal of human progress, he could have followed a program based on nationality, freedom, equality, and progress (assuming no other program existed) that his present accusers would have provided him with. Let us assume that this program could have been formulated and that Alexander would have acted according to it. What would then have become of the activities of all those people who opposed the government’s direction at the time, activities that historians consider to be good and beneficial? There would have been no activity; there would have been no life; there would have been nothing.
If we accept that human life can be governed by reason, we destroy the possibility of life.

If we assume, like historians do, that great individuals lead humanity towards achieving specific objectives, whether it be the greatness of Russia or France, the balance of Europe, the spreading of revolutionary ideas, overall progress, or any other goal, it becomes impossible to explain historical phenomena without considering the concepts of chance and genius.
If the aim of the European wars at the beginning of the current century was the greatness of Russia, that aim could have been achieved without all the preceding wars and without an invasion. If the aim was the greatness of France, that goal could have been reached without a revolution and without an empire. If the objective is the dissemination of ideas, printing would have been much more effective than soldiers. If the objective is the progress of civilization, then it is very easy to assume that, aside from the extermination of people and their wealth, there are other more efficient ways to spread civilization.
So why did things happen the way they did and not in a different manner?
Because that’s how it happened. “Chance created the situation; genius took advantage of it,” says history.
But what is chance? What is genius?
The words chance and genius do not represent anything that actually exists and therefore cannot be defined. The words only represent a certain level of understanding of phenomena. I do not know why a particular phenomenon occurs; I believe I cannot know; therefore I do not wish to know, and I say: chance. I observe a force that produces an action disproportionate to universal properties; I do not comprehend why it happens, and I say: genius.
For a herd of rams, the ram that is taken away by a shepherd every evening to a special pen to feed and becomes twice as large as the others, must appear to be a genius. And the fact that this very same ram does not enter the common sheepfold in the evening, but goes into a special pen with oats, and that this very same ram, covered in fat, is killed for meat, must seem like a remarkable combination of genius and several extraordinary coincidences.
However, rams should stop assuming that everything that is done to them occurs solely for the achievement of their own ram goals; it is worth considering that the events that happen to them may have purposes incomprehensible to them – and they will immediately perceive the unity, consistency in what happens to the fattened ram. Even if they do not know the purpose for which it was fed, they will at least know that everything that happened to the ram did not happen by chance, and they will no longer require the concepts of chance or genius.
Only by separating ourselves from the understanding of a close, comprehensible goal and acknowledging that the ultimate goal is beyond our reach, will we see coherence and expediency in the lives of historical figures; we will uncover the cause of their actions, which are disproportionate to universal properties, and we will no longer need the words chance and genius.
It is only necessary to recognize that the purpose of the unrest among European nations is unknown to us, but we are aware of the facts of murder, initially in France, then in Italy, Africa, Prussia, Austria, Spain, and Russia, and that the movements from west to east and east to west constitute the essence and purpose of these events. Not only will we no longer need to perceive exclusivity and genius in the characters of Napoleon and Alexander, but it will be impossible to imagine these individuals as anything other than ordinary men; and not only will it be unnecessary to attribute the minor events that shaped these men to chance, but it will be evident that all these minor events were necessary.
If we abandon the knowledge of the ultimate goal, we will clearly understand that just as it is impossible to conceive of any other plant with colors and seeds more suited to it than the ones it produces, it is equally impossible to conceive of two other individuals, with all their pasts, who would correspond to such an extent, in such minute details, to the purpose they were meant to fulfill.

The fundamental, essential meaning of the events in Europe at the start of the current century is the active movement of the masses of European peoples from the west to the east and then from the east to the west. The initial catalyst for this movement was the westward movement. In order for the peoples of the West to undertake the warlike journey to Moscow that they did, it was necessary (1) for them to form a warlike group of significant size that could withstand a clash with the warlike group of the East; (2) for them to abandon all established traditions and habits; and (3) for their warlike movement to be led by an individual who could justify the deceptions, robberies, and murders that accompanied it, both for himself and for them.
Since the French Revolution, the old, insufficiently large group has been dismantled; old habits and traditions have been eradicated; a new group of greater dimensions, new habits, and traditions has gradually emerged, and the individual who will lead the future movement and bear full responsibility for what is to be achieved has been prepared.
An individual with no firm beliefs, no ingrained habits, no extensive knowledge, no recognizable name, not even a Frenchman, by the strangest of circumstances manages to rise among all the parties relevant to France, and, without causing any harm to any of them, is elevated to a prominent position.
The ignorance of his companions, the weakness and insignificance of his adversaries, the sincerity of his falsehoods, and this man’s brilliant and self-assured charisma place him at the forefront of the army. The exceptional composition of the soldiers in the Italian army, the unwillingness of the opponents to fight, and the brash insolence and self-assurance earn him military acclaim. Numerous so-called coincidences accompany him wherever he goes. The disfavor he experiences with the rulers of France actually works to his advantage. His attempts to deviate from his predetermined path are unsuccessful: he is not accepted for service in Russia and fails in his attempt to reach Turkey. During the wars in Italy, he comes close to death multiple times, yet each time he is unexpectedly saved. The Russian armies, which could potentially ruin his reputation, for various diplomatic reasons, do not enter Europe as long as he is present.
Upon his return from Italy, he finds the government in Paris undergoing a process of decay that inevitably destroys those who become entangled in it. The only way out of this perilous situation for him is to embark on a purposeless, gratuitous expedition to Africa. Once again, the same so-called coincidences accompany him. The impregnable Malta surrenders without a single shot being fired; the most reckless dispositions succeed. The enemy fleet, which later on would not allow a single boat to pass, permits an entire army to pass. In Africa, a series of atrocities are committed against the nearly defenseless inhabitants. And the individuals who commit these atrocities, especially their leader, convince themselves that it is marvelous, that it is glorious, that it resembles the exploits of Caesar and Alexander the Great, and that it is righteous.

During the twentieth century, humanity has unlocked the enigma of the earth’s core through extensive research. Nowadays, even the youngest schoolchildren are familiar with the structure of the earth’s layers. For those who are still unaware of the earth’s composition and its main layers, as well as the name of its thinnest part, we will present several noteworthy details….

The form and dimensions of planet Earth

Contrary to popular belief, the Earth is not perfectly spherical. Instead, it has a shape known as a geoid, which is slightly flattened. The areas where the Earth is compressed are referred to as the poles. The Earth rotates on its axis, which passes through the poles, completing one revolution in a 24-hour period.

The equator, an imaginary circle, divides the geoid into the Northern and Southern hemispheres, encircling the middle of the planet.

Besides the equator, there are lines of longitude perpendicular to the equator and intersecting both poles. One of these lines, which passes through the Greenwich Observatory, is known as the Prime Meridian – it serves as a reference point for measuring longitude and determining time zones.

The main characteristics of the Earth are as follows:

• Diameter (km): Equatorial – 12,756, Polar (at the poles) – 12,713
• Circumference (km): Equator – 40,057, Meridian – 40,008

Therefore, our planet is shaped like an ellipsoidal geoid and rotates on an axis that passes through the North and South poles.

The equator, which is a circle dividing the Earth into two hemispheres, encircles the central part of the geoid. To determine the radius of the Earth, one can use half of the values for its diameter at the poles and the equator.

Earth’s Shells

The primary shells of the Earth are categorized based on their contents. Since our planet has a spherical shape, the shells that are held together by gravity are referred to as spheres. When examining the Earth’s structure in cross-section, three spheres can be observed:

In sequential order (starting from the planet’s surface), they are arranged as follows:

1. Lithosphere – the solid outer shell of the Earth, which consists of its mineral layers.
2. Hydrosphere – encompasses the planet’s water resources, including rivers, lakes, seas, and oceans.
3. Atmosphere – the atmospheric shell that surrounds the planet.

Additionally, there is the biosphere, which encompasses all living organisms that inhabit the other shells.

Important! Many scientists consider the planet’s population to be a distinct extensive shell known as the anthroposphere.

The Earth’s components – lithosphere, hydrosphere, and atmosphere – are distributed based on the combination of homogeneous elements. The lithosphere consists of solid rocks, soil, and the planet’s inner contents, while the hydrosphere contains all of its water, and the atmosphere includes all of the air and other gases.

Atmosphere

The atmosphere is an envelope of gases. It is composed of oxygen, nitrogen, carbon dioxide, gas, and dust.

Based on the oxygen content and temperature, the atmosphere is divided into several main layers:

1. Troposphere – the uppermost layer of the Earth, containing the majority of the planet’s air and extending from the surface to a height of 8-10 km (at the poles) to 16-18 km (at the equator). Clouds and various air masses form in the troposphere.
2. The stratosphere is a layer where the concentration of air is significantly lower compared to the troposphere. It has an average thickness of 39-40 km. This layer begins at the upper boundary of the troposphere and extends up to an altitude of approximately 50 km.
3. The mesosphere is a layer of the atmosphere that stretches from 50-60 to 80-90 km above the Earth’s surface. It is characterized by a continuous decrease in temperature.
4. The thermosphere is situated approximately 200-300 km from the planet’s surface and differs from the mesosphere in its temperature increase with altitude.
5. The exosphere starts from the upper boundary below the thermosphere and gradually transitions into outer space. It is characterized by a low concentration of air and high solar radiation.

Caution. There exists a slender layer of ozone in the stratosphere, situated approximately 20-25 km above the Earth’s surface, that shields all forms of life on our planet from the harmful effects of ultraviolet radiation. In the absence of this vital shield, every living organism would face imminent extinction.

The Earth’s atmosphere is a vital component for sustaining life on our planet.

It provides the necessary air for organisms to breathe, regulates weather conditions, and shields the Earth from the harmful effects of solar radiation.

Comprised mainly of nitrogen (70%), oxygen (21%), carbon dioxide (0.4%), and other rare gases, the atmosphere plays a crucial role in maintaining the delicate balance of life on Earth.

Furthermore, an essential part of the atmosphere is the ozone layer, located approximately 50 km above the Earth’s surface.

The hydrosphere encompasses all the liquids found on our planet.

This encompasses various water sources which differ in location and salinity:

• The Earth’s oceans cover a vast area with saltwater, including four main oceans and 63 seas.
• The surface waters of the continents consist of freshwater and occasionally brackish water. They can be further classified into flowing bodies of water such as rivers, and standing bodies of water such as lakes, ponds, and swamps.
• Groundwater refers to freshwater located beneath the Earth’s surface. This water can vary in depth from 1-2 meters to over 100-200 meters.

It is worth noting that a significant portion of freshwater exists in the form of ice. Currently, there are approximately 34 million km3 of freshwater reserves in permafrost zones, including glaciers, massive icebergs, and perpetual snow that never melts.

The hydrosphere is primarily responsible for providing clean drinking water and plays a significant role in shaping the climate. Additionally, water resources serve as transportation routes and popular destinations for tourism and leisure activities.

The Earth’s Crust

The lithosphere consists of the solid mineral layers of the Earth, with a thickness ranging from 100 kilometers under the seas to 200 kilometers under the continents. It encompasses the Earth’s crust and the upper part of the mantle.

Beneath the lithosphere lies the internal structure of our planet.

The plates of the lithosphere are primarily composed of basalt, sand, clay, stone, and a ground layer.

The structure of the Earth, including the lithosphere, can be illustrated by the following layers:

• The upper layer of the Earth’s crust is composed of various types of rocks, including sedimentary, basaltic, and metamorphic rocks, as well as fertile soil. Depending on the location, there are two types of crust: continental and oceanic.
• Beneath the Earth’s crust lies the mantle, which accounts for approximately 67% of the planet’s total mass. This layer has a thickness of about 3000 km. The upper portion of the mantle is viscous and can be found at depths ranging from 50-80 km under the oceans to 200-300 km under the continents. The lower layers of the mantle are denser and more rigid. The mantle is primarily composed of heavy materials such as iron and nickel. Many geological phenomena, including seismic activity, volcanic eruptions, and the formation of mineral deposits, are a result of processes occurring within the mantle.
• Important! There is a theory among a limited group of scientists that, in addition to the traditional model of a partially molten heavy core, there is an inner luminary at the center of the planet, surrounded by a substantial layer of water. This theory, while only embraced by a small community within the scientific field, has gained widespread popularity in fantasy literature. A prime example is V.A. Obruchev’s novel “Plutonia,” which depicts a Russian scientific expedition to the inner cavity of the planet, complete with its own miniature luminary and a world inhabited by extinct animals and plants on the surface.

Important! Among a narrow circle of scientists, in addition to the classical model with a semi-molten heavy core, there is a theory that in the center of the planet there is an inner luminary, surrounded on all sides by an impressive layer of water. This theory, except for a small circle of adherents in the scientific community, has found a wide distribution in fantasy literature. An example is the novel “Plutonia” by V.A. Obruchev, which tells about the expedition of Russian scientists to the cavity inside the planet with its own small luminary and a world of extinct animals and plants on the surface.

The commonly accepted model of the Earth’s structure, which includes the crust, mantle, and core, is continuously being enhanced and refined each year.

With the advancement of research methods and the introduction of new equipment, many aspects of the model will be updated multiple times.

For instance, determining the exact distance to the outer part of the core will require years of scientific investigation.

Currently, the deepest man-made mine in the Earth’s crust is around 8 kilometers deep, making the study of the mantle and, especially, the core of the planet only possible in a theoretical context.