Rafael A. Rivera Vazquez: Our planet and the gravity force

I often wonder, how would our planet without gravity. We have seen on television many times as astronauts float on other planets, and I would be like if we lived like this. We see the spacesuits used for subsistence and as they have to adapt to these conditions in this atmosphere. It is fascinating to see how the physical laws governing the universe and how the spacecraft can overcome the barrier of gravity and reach so distant planets.

The first approach about gravity was raised by Isaac Newton, who said that this is an instantaneous force. Newton was one of the first physicists seeking to find a complete explanation about gravity, however, although Newton's efforts were remarkable, 

and allowed explain the motion of the planets, there were other events that are not fully complied with their predictions.

Later the scientist Albert Einstein formulated a reasoning based on their theory that nothing can travel faster than light. So imagine the following scene, the sun emits its light and this comes to us about 8 minutes later, due to the distance that separates us, which is about 150 million kilometers. Now suppose the sun suddenly disappears, it is curious to know if this happens on earth we would still eight minutes of light. However, Newton claimed that gravity was an instant force and therefore disappear when the force of gravity that keeps the earth revolving around the sun disappears, so this would come out fired long before the light strike with to the earth. But after much reasoning Einstein came to a great explanation, which argued that where gravity was everywhere where a body exists, not as a force in itself, but as geometry, the presence of a body in space deformed "space-time" and this deformation was what attracted the bodies between them. Einstein deduced that space and time are deformed by the presence of a mass. 

Gravity is the force of attraction between two bodies that have mass, the greater the mass stronger gravity.

The Earth revolves around the sun, the moon around the earth. This is due to the gravitational force between these two bodies, both the moon and tide sun gravitation attract the sea, the moon with greater intensity. Thanks to gravity we have atmosphere, thanks to the atmosphere we have air, which enables us to live. The moon with greater intensity. But if gravity were suppressed on earth would end life mainly by the lack of air or would have to adapt to another way of life if possible. These are just some examples of how physics affects our lives, and how to meet and learn from it helps us to find solutions and solve problems.