Timeline of the Universe before the advent of planet Earth
The history of the Earth before the appearance of hominids
Main article: The history of the Earth before the appearance of hominids
Kernel
The planet was formed from asteroids that collided with each other and generated a huge amount of energy, which led to the "melting" of the planet. Heavy metals, such as iron, sank to the center of the planet, forming a core, and the liquid rock is outside and cools over time.
Today, the inner core looks like a solid metal ball. At the same time, it is heterogeneous and created from different "tissues." The core resembles a planet inside the planet - it rotates, is also heterogeneous and separated by the "ocean" of molten iron.
The presence of a nucleus creates a magnetic field that makes the existence of life on Earth possible, but it remains a mystery how the nucleus was formed, grew and developed. Researchers are constantly trying to find the answer to this question[1].
Magnetic field
The protective field of magnetic energy surrounding the Earth is created by convection inside the liquid outer core, which extends 2,260 kilometers above the solid core. The molten metal rises above the solid inner core, cools as it approaches Earth's rocky mantle, and sinks. This circulation generates bands of electrons enveloping the planet. Without a solid inner core, this field would be much weaker and the planet's surface would be bombarded by radiation and solar winds that would destroy the atmosphere and render the surface uninhabitable.
2.58 million hp: Magnetic inversion Gauss - Matuyama. Beginning of Quaternary and Pleistocene
The Gauss-Matuyama magnetic inversion is a geological event that occurred about 2.58 million years ago, when the Earth's magnetic field changed direction.
Atmosphere
The Earth became suitable for aerobic life about 2.4 billion years ago, when photosynthetic microbes, and then plants, began to produce oxygen in large quantities.
Oxygen content in the atmosphere will begin to decline sharply in 1.1 billion years due to the heating of the planet by the Sun
The modern atmosphere of the Earth is highly oxygenated - its share is about 20%. This is one of the defining features of our planet, ensuring the maintenance of life on it. However, the life of oxygen biosignatures in the atmosphere is still unknown, especially when it comes to the distant future. For March 2021, scientists are concerned that the oxygen saturation of the earth's atmosphere may decrease over time.
In their study, specialists from the Georgia Institute of Technology (USA) and Toho University (Japan) studied the long-term stability of the Earth's atmospheric oxygen[2]
They conducted simulations of all Earth's systems using a combined model of biogeochemistry and climate to study the likely timing of high-oxygenated atmospheric conditions. Previously, similar experiments were carried out, but individual systems were usually modeled. The new modeling was more complex than usual - it was based on 400 thousand simulations.
The researchers found that Earth's oxygenated atmosphere was likely to persist for another 1.1 billion years before oxygen levels began to drop comparatively quickly.
According to the simulation, the main reason for this will be the Sun. "With age," the Sun will become brighter and warm, as a result of which the temperature on the surface of the Earth will rise, and carbon dioxide in its atmosphere will collapse. These two factors will kill the life of plants, thereby depriving the planet of its main source of oxygen.
Modeling also predicts that the oxygen content will fall to the levels characteristic of the Earth during the Archean era - the oldest stage in the life of our planet, when volcanoes seethed on it, and meteorites bombarded its surface from space.
After a sharp drop in oxygen levels, the Earth's atmosphere will be heavily saturated with methane. It will also be characterized by low levels of carbon dioxide and the absence of an ozone layer, that is, our planet is likely to be a place for anaerobic life.
Yes, it may seem that this find does not directly affect our lives today - according to many forecasts, people will disappear from the surface of the Earth altogether in a billion years. But the discovery makes it harder to find signs of alien life. Because oxygen is so inextricably linked to life on Earth, astronomers have long considered it a useful reference point for searching exoplanet atmospheres, where it can indicate the existence of extraterrestrial life.
Now it is becoming clearer that it is not enough to look for worlds that are at the right point in the space of the universe so that they can be populated - the right moment in time is also very important. The authors of the study calculated that oxygen is in the atmosphere of the planet only for 20-30% of its total life.
Muons
Main article: Muons
Water
The Earth's surface is more than 510 million square kilometers. Less than 30% of them are land. The rest is water.
Fresh water - 3% of all water
Most of our planet is covered in water - but fresh water accounts for just 3% of all water on Earth, and only 1% of fresh water is available as potable water. The rest is groundwater (30%) and glaciers (69%).
The availability of water varies greatly between countries around the world. As of 2022, the countries of Central Asia are leading in terms of water consumption per capita. 10 included Turkmenistan (the first place in the world, 5.7 thousand cubic meters of water per person per year), Uzbekistan (4th place, 2.1 thousand), Tajikistan (6th place, 1.6 thousand) and Kyrgyzstan (8th place, 1.5 thousand).
Against this background, 425 cubic meters of water per person per year in Russia looks very modest - and quite in line with other European countries (Germany, France, Austria - everywhere is consumed in the range from 400 to 500 cubic meters of fresh water per person per year) and exactly the same as in China.
By comparison, in many countries in Africa, fresh water consumption is in the region of 20 cubic meters per person per year.
Oceans
Provinces with low displacement rates
Using seismic tomography, experts looked under the earth's surface and found two giant droplets in the lowest part of our planet's mantle under Africa and the Pacific Ocean. In size, they make up from 3 to 9% of the Earth's volume. The two structures are known as large low-displacement-rate provinces (LLSVPs). Scientists call them droplets as energy waves move more slowly through them than through the surrounding lower mantle.
Analyzing the find, scientists suggest that a section of "Ace" may be hidden under Africa, the height of which is 800 km (about 90 peaks of Everest).
Since the objects are somewhat denser than the mantle surrounding them, scientists have suggested that they consist of a different material. Which one is unknown.
It is suggested that LLSVPs may have been formed by different pathways. The province under Africa can be a submerged and accumulated billions of years piles of oceanic crust. And the province under the Pacific Ocean may be pieces of the ancient planet Teya, which is identical in size to Mars.
The hypothetical planet Teia collided with Earth about 4.5 billion years ago, throwing away enough stone to form the moon.
The researchers hypothesized that the structures found under the Pacific Ocean could be Teya particles -- a denser mantle of a protoplanet that mixed with the Earth's mantle as a result of the collision.
Continents
- Arctic
- Africa
- Antarctica
- Australia
- Eurasia
- North America
- South America
Islands
Earthquakes
Main article: Earthquakes
Climate
Main article: Climate change on Earth
Rotation of the Earth
2021: Earth began to spin faster, so 2021 will be shorter than 2020
In mid-January 2021, specialists from the All-Russian Research Institute of Physical, Technical and Radio Engineering Measurements came to the conclusion that in 2020 the Earth rotated faster than usual, and the coming 2021 will be shorter than the previous one (excluding February 29 in leap 2020).
In 2020, Earth broke the previous record for the shortest astronomical day, set in 2005. In general, scientists have identified at once the 28 fastest days in the history of observations (since 1960). Moreover, the Earth continues to rotate just as quickly.
 | When high-precision atomic clocks were developed in the 1960s, they showed that the duration of the average solar day can vary by several milliseconds, experts explained on the TimeandDate.com, and the speed of rotation of the Earth can depend on various factors. |  |
| | Changes in the atmosphere, especially atmospheric pressure around the world, and wind movements that may be associated with climate events such as El Niño [a fluctuation in the temperature of the surface layer of water in the equatorial Pacific Ocean, which has a noticeable impact on the climate note - TAdviser], strong enough that their influence can be observed in the speed of rotation of the Earth, atmospheric scientist at VNIIFTRI's Atmospheric and Environmental Research Division David A. Salstein said. | |
The Earth has been slowing down over the past decades. When the time it takes for the Earth to fully rotate deviates from Coordinated Universal Time (UTC) by more than 0.4 seconds, UTC time is corrected. Scientists added an "extra second" on average every year and a half. The latter was added on December 31, 2016. But as Earth accelerated again, scientists believe every astronomical day in 2021 will be 0.05 milliseconds shorter, with a difference of 19 milliseconds within a year.
| | It is possible that if the Earth's rotation speed increases further, it will take a negative additional second, but it is too early to talk about this, physicist Peter Whibberley from the UK National Physical Laboratory told The Telegraph .[3] | |
Ecology in the world
Main article: Ecology in the world
Living Beings
As of 2020, 3 decillion (3 with 33 zeros) living beings live on Earth, of which 75% are bacteria.
The population of the Earth
Fauna
2020: The number of wild animals in the world has decreased by 73% in 50 years
From 1970 to 2020, wildlife populations on a global scale decreased by an average of 73%, approaching critical levels. This is stated in a study by the Zoological Society of London, the results of which are presented on October 10, 2024.
Experts analyzed the populations of 5495 species of wild animals around the world: amphibians, birds, fish, mammals and reptiles. It was found that freshwater populations were hardest hit, decreasing by 85% over the specified 50-year period. This is followed by populations of terrestrial animals, which showed a decrease of 69%. Marine populations declined by 56%.
The most critical situation is observed in the Caribbean and Latin America, where wildlife populations decreased by about 95% during 1970-2020. Then come Africa (a 76% reduction in 50 years), Asia and the Pacific (minus 60%), North America (minus 39%) and Europe (minus 35%).
The authors of the report cite several main reasons that provoke a rapid decline in the number of wild animals around the world. This is, in particular, human activity related to the consumption of natural resources and the production of food. Another important factor is climate change, which is especially pronounced in Latin America and the Caribbean. At the same time, in North America, as well as in Asia and the Pacific region, environmental pollution has a negative impact on populations.
| | Nature disappears at a frightening rate. While some changes may be relatively small, their cumulative impact can provoke large-scale problems. Ultimately, this could lead to abrupt and potentially irreversible changes, the researchers say.[4] | |
Countries of the world
3D models of the Earth
2023: The most geologically accurate model of the Earth presented
In early March 2023, scientists from the University of Sydney in Australia presented what they said was the most detailed model of geological changes on Earth. Using a structure involving geodynamics, tectonic and climatic forces, the researchers built a dynamic model. This is the first computer simulation of the last 100 Ma with a high resolution of up to 10 km. The technology is called Global Scalable Paleo Landscape Evolution (goSPL). Read more here.
2020: Roscosmos will launch satellites to create a 3D model of the Earth
On October 8, 2020, it became known about the plans of Roscosmos to create a 3D model of the Earth using the Aist-2T satellites, the launch of which is scheduled for 2022. This was announced by Valery Zaichko, Deputy Director of the Department of Navigation Space Systems (GLONASS) of Roscosmos. Read more here.
Monitoring
2020: Microsoft launches' planetary computer 'to collect, store and analyze Earth state data
On April 15, 2020, Microsoft announced the launch of the Planetary Computer project to collect, store and analyze data on the state of the Earth. With this initiative, the American company continued to work on the conservation of biodiversity and natural ecosystems under the AI for Earth program. Read more here.
Notes
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