16 facts about Milky Way
A galaxy is a gravitationally connected system of stars, dust, gas, and dark matter. It is estimated that there are almost 3.9 trillion of them in the ...
Although 4 billion years ago no sane person would have given the Earth a chance to support life, today it is a concentration of countless forms of living organisms. So far it's leading, life has not yet been found anywhere outside Earth.
It is also the first planet from the sun to have a natural satellite.
The equatorial radius of the Earth is 6.378,137 km.
For its first billion years, it was a hostile, harsh, rocky place where life did not exist. According to research, the first living organisms appeared in Earth's oceans about 3.5 billion years ago.
Nitrogen makes up about 78.1 percent of the atmosphere, oxygen 20.9 percent, and Argon 0.93 percent. The other gases that can be found in the Earth's atmosphere are neon, helium, methane, krypton, and hydrogen.
It is divided into layers, the lowest of which is the troposphere (6 to 20 km), then the stratosphere (20 to 50 km), mesosphere (50 to 85 km), thermosphere (85 to 690 km), and exosphere (690 to 10,000 km).
At first, it was surrounded by a primordial atmosphere, which consisted of the remains of proto-planetary gas, mainly hydrogen and helium. As the proto-planetary disk thinned, these gases escaped from Earth's atmosphere into space.
After that, the first atmosphere appeared - it was created from degassed matter that fell to Earth during cosmic bombardments. Most (about 80 percent) was water vapor. The remaining gases were: carbon dioxide, methane, hydrogen sulfide, ammonia, carbon monoxide, and nitrogen. The first atmosphere was formed about 4 billion years ago and the high content of greenhouse gases made the Earth a very hot place.
The second atmosphere was formed when most of the water vapor condensed and fell to Earth as precipitation. The most common gas in the atmosphere at that time was carbon dioxide.
The third atmosphere was created thanks to the first living organisms, inhabitants of the oceans - which began to produce oxygen in the process of photosynthesis. Since then, oxygen has been continuously present in the atmosphere and provides living conditions for most organisms.
As much as 75 percent of the atmosphere is at an altitude of less than 11 kilometers. With each additional kilometer, its density dilutes due to its decreasing gravity. The conventional boundary separating the atmosphere from space is the Kármán Line, located at an altitude of 100 km above sea level.
The average distance from the Sun is 150 million km and ranges from 147.09 million km at the periapsis to 152.09 million km at the apsis.
According to the most common division, there are Europe, Asia, North America, South America, Africa, Australia, and Antarctica. From a geological point of view, however, Europe and Asia form one continent - Eurasia.
We distinguish oceans: Pacific, Atlantic, Indian, Southern, and Arctic. The basic ones are considered to be Pacific, Atlantic, and Indian. All ocean waters combined into one whole are called the universe.
Below you will find a short list of the most important organisms along with the approximate number of species described.
The Earth is therefore a slightly flattened ball - this shape is called a geoid.
It is made of an alloy of nickel and iron with small admixtures of other elements. It reaches temperatures from 5500 to 6500 degrees Celsius and the pressure there is 13.5 million atmospheres.
The peak is 8848 m above sea level. However, Mount Everest is not the farthest point from the center of the planet, because this title goes to the top of the Chimborazo volcanic mountain located in Ecuador.
The depth of the trench located in the Pacific Ocean at its lowest point is 10.924 m below sea level. The immersion record in the Mariana Trench was set on March 26, 2012, by director James Cameron, who descended to a depth of 10.898 meters on board the one-man submersible "Deepsea Challenger".
It is trapped in the soil in the form of various oxides, the most common of which are: silicon dioxide, aluminum oxide, calcium oxide, magnesium oxide, and iron oxide.
It is made of tectonic plates that are constantly moving. Earthquakes may occur in zones where these plates collide and rub against one another. In such areas, mountains also rise or create faults (e.g. the Mariana Trench). The largest tectonic plates on Earth are Pacific, African, North American, Eurasian, Antarctic, Indo-Australian, and South American.
Most of the plate is submerged under the ocean, the land area of the Pacific plate is only a part of the California coast, Baja California, and New Zealand. The Pacific tectonic plate has a hot spot (underground heated area) from which the Hawaiian islands rose.
The moon is relatively large for a natural satellite. Its diameter is approximately ¼ the diameter of the Earth. It orbits the Earth at an average distance of 384.400 km.
In the first million years of the Earth's existence, the day lasted only four hours. From the very beginning, the Earth has been losing energy as it rotates around its axis, which translates into lower and lower rotational speed and longer days. In the early days of dinosaurs, the day lasted about 22 hours, and at the end of their existence, 66 million years ago, it lasted about 23 hours. We will reach 25 hours a day in about 200 million years.
Life on the surface of our planet has been wiped out many times by great cataclysms called great extinctions. However, after each such event, living organisms were reborn, and thus life on Earth has continued uninterrupted for billions of years. However, the final blow to our home planet will be the expansion of the dying Sun, which in about 7.6 billion years will expand its atmosphere so significantly that it will absorb the Earth.
As hydrogen deposits in the solar core decrease, the star's brightness is expected to increase. In just over a billion years the sun will shine 10 percent brighter and in 3.5 million years it will shine 40 percent brighter. In such conditions, all surface water on the planet will evaporate and the Earth will turn into a hellishly hot and uninhabitable place.
This is because the Northern Hemisphere accounts for 68 percent of all landmass. It is estimated that in the future up to 90 percent of the population may live in this part of the globe.
This is followed by wasteland and wilderness (24 to 31 percent), human forests (16 to 27 percent), arable farms (12 to 14 percent), and infrastructure (1 percent).
It took humanity over 2 million years to reach a population of one billion. In 2011, there were 7 billion of us and we are already reaching 8. According to estimates, by 2050 there will be 9 to 10 billion people on Earth and 10 to 12 by the end of the 21st century.
