The earth It is the third planet from the Sun and the largest of the terrestrial planets. Surprisingly, while it is only the fifth largest planet in terms of size and mass, it is the densest (5,513 kg/m3) of all the planets.
The earth It is the only planet in the solar system that is not named after a mythological being. Its name is derived from the Old English word «ertha» and the Anglo-Saxon word «erda», which means soil or earth.
Likewise, the Land It formed about 4.54 billion years ago and is currently the only known planet to support life, and a lot of it.
Profile of Planet Earth
Equatorial diameter: 12,756 kmPolar diameter: 12,714 kmMass: 5.97 x 10^24 kgMoons: 1 (The Moon)Orbit distance: 149,598,262 km (1 AU)Orbit Period: 365.24 daysSurface temperature: -88 to 58°C
The earth It is the third planet from the Sun and is the largest of the terrestrial planets. Earth is the only planet in our solar system not named after a Greek or Roman deity.
Similarly, the Earth was formed about 4.54 billion years and it is the only planet known to support life.
Throughout human history we have tried to understand our home planet. However, the learning curve has been steep, with many mistakes along the way.
For example, it wasn’t until the time of the ancient Romans that the world was understood to be spherical rather than flat.
Sun
A second example is the belief that the Sun revolved around the Earth. Only in the 16th century, through the work of Copernicus, did we accept that the Earth was in fact merely a planet orbiting the Sun.
Perhaps most importantly, it is during the last two centuries that science has allowed us to see that Earth is an ordinary and unique place in the Solar System.
For one, many of its features are unexceptional. Take for example its size, interior and geological processes being the fifth largest of the eight planets, it is close to the median in terms of size.
Its interior structure is almost identical to that of the other three terrestrial planets; and the same geological processes that shape its surface can be found not only on other planets, but also on planetary moons.
However, Earth is special in one very important aspect in the entire solar system, Earth is the only world known to support life.
Atmosphere
The Earth’s ability to support life depends in many ways on its atmosphere. The composition of the atmosphere is approximately 78% nitrogen (N2), 21% oxygen (O2), 1% argon, with traces of carbon dioxide (CO2) and other gases.
Nitrogen and oxygen are essential for the production of DNA and biological energy, respectively, without which life could not be sustained.
In addition, oxygen found in what is known as the ozone layer of the atmosphere protects the planet’s surface by absorbing harmful solar radiation.
Notably, the significant amount of oxygen present in the atmosphere is due to life found on Earth.
As a byproduct of the production of sugars, plants convert carbon dioxide in the atmosphere into oxygen.
Essentially this means that without the plants the amount of carbon dioxide in the atmosphere would be much higher and the oxygen levels much lower.
For one thing, if carbon dioxide levels were much higher, it’s likely that Earth would suffer from a runaway greenhouse effect like the one on Venus.
Similarly, if the percentage of carbon dioxide were lower, there would be no greenhouse effect, so temperatures would be much colder.
Additionally, carbon dioxide levels are adequate to maintain hospital temperatures ranging from -88°C to 58°C.
oceans
When Earth is viewed from space, there is one overwhelming feature: oceans of liquid water.
In terms of surface area, these oceans cover approximately 70% of the Earth. What is even more amazing than this percentage is that a single drop of liquid water has yet to be found on any other planet in the Solar System. In this sense, the Earth is truly unique.
Like Earth’s atmosphere, the presence of liquid water is vital to life. In fact, life is believed to have first developed 3.8 billion years ago in the oceans, only later developing the ability to survive on land.
The existence of the oceans is attributed to two sources. The first of these is the Earth itself. It is conjectured that large amounts of water vapor were trapped in the Earth during its formation.
Over time, the planet’s geological mechanisms, primarily its volcanic activity, released this water vapor into the atmosphere.
Once in the atmosphere, this vapor condensed and fell to the planet’s surface as liquid water.
The second source is theorized to have originated from ancient comets that struck Earth.
At the time of impact, they deposited substantial amounts of water ice on the planet.
Surface
Although most of the Earth’s surface lies under its oceans, the remaining «dry» surface is quite remarkable.
When comparing the Earth with other solid bodies in the Solar System, its surface stands out for the absence of impact craters.
It is not that the Earth has been spared from the numerous impacts of small bodies; rather, it is because the evidence of these impacts has been erased.
Although there are many geological processes responsible for this, the two most important are weathering and weathering.
In many ways, these two mechanisms can be thought of as working in tandem.
Weathering is the breaking down of surface structures into smaller pieces by the atmosphere.
Acid rain
Also, there are two types of weather exposure: chemical and physical. An example of chemical erosion is acid rain. An example of physical erosion is the abrasion of river beds caused by rocks suspended in running water.
The second mechanism, erosion, is simply the movement of particles worn away by water, ice, wind, or gravity.
Thus, impact craters have been «smoothed» through erosion and erosion by being separated and redistributed to other areas of the Earth’s surface.
Two other geological mechanisms have helped shape the Earth’s surface. The first is volcanic activity.
This process consists of the release of magma (molten rock) from the interior of the Earth through a break in its crust.
Some effects of volcanic activity can be the resurfacing of the earth’s crust or the formation of islands (think of the Hawaiian Islands).
The second mechanism is orogeny, or the formation of mountains through the compression of tectonic plates.
An example of mountains created through this process is the Rocky Mountains.
Inside
Like the other terrestrial planets, Earth’s interior is believed to consist of three components: a core, a mantle, and a crust.
The nucleus
At present, the core is believed to be composed of two separate layers: an inner core made of solid nickel and iron, and an outer core made of molten nickel and iron.
The mantle is a very dense and almost totally solid silicate rock; its thickness is approximately 2,850 km.
Finally, the crust is also made up of silicate rock and varies in thickness. While the continental crust is between 30 and 40 km thick, the oceanic crust is much thinner, only 6 to 11 km.
Another distinguishing feature of Earth compared to other terrestrial planets is that its crust is divided into cold, rigid plates that rest on the warmer mantle below.
Furthermore, these plates are in constant motion. Along the boundaries of these plates, two processes can occur, known as subduction and propagation.
During subduction two plates come into contact (sometimes violently, producing earthquakes) and one plate is forced under the other.
Separation, on the other hand, is when two plates move away from each other.
orbit and rotation
At approximately 365 days, Earth’s orbit around the Sun is familiar to us. The length of our year is due in large part to Earth’s mean orbital distance of 1.50 x 108 km.
What many people are not familiar with is that at this orbital distance it takes light from the sun, on average, about eight minutes and twenty seconds to reach Earth.
With an orbital eccentricity of 0.0167, Earth’s orbit is one of the most circular in the entire Solar System.
This means that the difference between Earth’s perihelion and aphelion is relatively small.
As a result of this small difference, the intensity of sunlight received by Earth remains nearly constant throughout the year.
However, the Earth’s position in its orbit is responsible, in part, for the different seasons it experiences.
the inclination
The axial tilt of the Earth is approximately 23.45°. That is, the axis on which the Earth rotates is slightly tilted with respect to the plane in which the Earth orbits the Sun.
The effect of this tilt, together with the position of the Earth in its orbit, means that at certain times the amount of sunlight that the northern hemisphere receives is greater than that of the southern hemisphere, and vice versa.
This variation in intensity is what produces the warmest temperatures during the summer and the coldest during the winter.
A second commonly known feature is that it takes the Earth approximately twenty-four hours to complete one rotation.
This is faster among terrestrial planets, but easily slower than all gas planets.
the earth is different
There are many things that make Earth unique among the planets in the Solar System. First, Earth is the only planet we know of that contains life.
Earth not only contains life, but supports millions of different life forms. Another difference is that the Earth is mostly covered in water. About 71% of the Earth is covered in saltwater oceans.
Earth is the only planet that has liquid water on its surface. Also, Earth’s atmosphere is made up mostly of nitrogen and oxygen, while the atmospheres of Venus and Mars are made up mostly of carbon dioxide.
Earth Geography
The earth has seven large land masses called continents.
The continents include:
Africa.Asia.North America.South America.Europe.Oceania.The antartida.
It also has 5 large bodies of water called oceans, including the oceans:
Atlantic.Peaceful.Indian.Southern.Arctic.
The highest point above sea level on Earth is Mount Everest and the lowest point is the Mariana Trench.
Composition of the Earth
The Earth is made up of several layers. On the outside is a rocky layer called the Earth’s crust. Beneath this is the mantle followed by the outer core and…