The earth is the geoid-shaped place where human beings coexist as an advanced civilization (this last adjective is something relative to tell the truth), in addition to the place, it represents the world that we experience throughout our entire life. life full of feelings and emotions of pain, sadness, joy, happiness, love, hate, pleasure, suffering, anger, disappointment, pride, motivation, envy, solidarity, compassion, and all other expressions with their consequences referring to this characteristic. This is a proper way of seeing our planet, within the limits that come to define such perception, because it is very difficult to have the vision or the complete picture of what the earth really is at all times.

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The earth

Our planet is the third in order of proximity to the Sun with a distance of [1]and the fifth by its equatorial radius size of [2], follows an elliptical trajectory around the Sun given to the law of universal gravitational force and following Kepler's first law of orbits.

It has a moderately dense atmosphere consisting of 78% nitrogen, 21% oxygen, and 1% argon with other gases at an altitude of 70 km, from 800 km it contains 50% helium and 50% hydrogen, so Generally, almost half of its surface is constantly covered by clouds.

About 70% of the earth's surface is covered by water, and although only 2.5% is fresh water, it is the only planet known to date that has a body of water, as well as the large proportion of oxygen in our atmosphere.

With a mass of [3], considerable amount to exert a gravitational force towards the center of the earth on the bodies that are on or near its surface, generating an acceleration of free fall and whose magnitude varies according to our position on the planet, it is clear that due to the flattening at the poles the objects weigh slightly more on it than the equator, which is why it is possible to lasso a spear or javelin 70 meters at the poles, and reach a greater distance at the equator using the same force.

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Motion

In appearance we perceive the earth as static and immutable, but the truth is that it moves fairly quickly and constantly. The most popular movements are the rotation around its axis, and the translation around the sun, thus producing the periodic changes we know as day, night and year.

Being more specific our planet earth turns from west to east with a speed of in the Equator, and descends as it approaches the poles, it moves to originate thus the seasons, the variations with respect to the distance to the sun is between the perihelion (closer) in January and the aphelion (further) in July.

_Fuente

Seismic movements provide a very important source of data to know the internal structure of the globe, every time an earthquake occurs, the movement generates waves that propagate through the mass of our planet, these waves are detected by means of instruments called seismographs. At this point it is known that the speed of the waves and the direction in which they spread depends on the characteristics of the material they must pass through, so when evaluating this parameter it has been possible to deduce that the earth is internally constituted by three layers: bark , mantle and core

These are the aspects that generally teach us, but there are many other factors that are interesting in particular, rather than factors, questions I would say about our planet. Perhaps these questions are somewhat stupid, but if that were the case, the answer could also be of the same nature, however, it is about knowing and having a clearer vision of the physics that govern our world. As for example, is the escape velocity the same at all points of the earth? As far as most of the places from which rockets are launched into space are located in the northern hemisphere, if it were possible to launch a rocket near the Equator would it be easier to reach the escape velocity?

These are questions that make me curious, but to understand the answer you have to know a little beyond the basics. I hope to find answers to these simple questions soon and share it here on the net