Explanation of How Earth Came into Existence
It all started with a tremendous explosion. Somewhere in our galaxy, a star exploded, sending masses of gas and dust. This supernova, since these explosions are called, took place there are about 5 billion years. The remains of the explosion, and then crashed into a nearby gas cloud that brings together the ingredients to form our solar system.
Because the explosion was so strong that made the hot dust mixture and things started to cook. Small dust particles began to coalesce, making increasingly large pieces and the mixture began to meet under its own gravity.
Finally, the central node has become so hot and dense that began to produce its own electricity, lighting nuclear fires. This was the birth of our sun. The remaining mixture swirled dust around the star, which takes place on a disk.
Gradually the sun grew in size and the dust disk cools. For millions of years grouped into grains of dust and clods, stones and possibly planetesimals – fairly large pieces of rock to have its own gravitational field. Some of these planetesimals became the embryonic forms of the planets in our solar system today.
Gradually, these rocky planets began to organize the solution at a comfortable distance from the sun and the search for its own orbit. Earth found its way as the third planet from the sun. In the early days, rock stacks were still common, leaving craters on the surface of all the planets.
One of these collisions, there are about 4.5 billion years, is believed to have nearly destroyed the Earth, and was probably responsible for our honeymoon. A large planetesimal, about the size of Mars, the Earth took a glancing blow by throwing a piece of bark from the Earth into space. Some of the planetesimals have merged with it, while the bulk expelled began its own orbit around the Earth and became the moon.
The proof of this theory comes from the lunar dust samples, showing that the moon is made of rock quite similar to those found in the upper layers of the mantle and the crust of the Earth.
The accident in the formation of the Moon hit the Earth on the side, changing its angle to the sun 0 degrees to 23.5 degrees. Consequently, the Earth began to have seasons: winter for the hemisphere tilted away from the sun, and summer for the hemisphere tilted toward the sun.
Early Earth was a very different world in which we live today instead. First, the world has not had a crust, mantle, and core, and instead of all the elements were mixed uniformly. There were no continents or oceans and no atmosphere. meteoritic collisions, radioactive decay, and the global compression made the earth gets warmer. After a few million years, the temperature of the Earth has reached 2,000C – the melting point of iron – and the core of the Earth was formed.
At this point, much of the land was melted and may have been an ocean of magma to the surface. Gradually cooled the Earth and the planet has been exposed in a core, mantle, and crust. This stratification of the planet helped trigger plate tectonics on the surface, and the Earth began to look a little more like the world we know today.
Most geologists believe that the atmosphere and the oceans of the world came there about 4 billion years – the product of multiple volcanic belching. Alternatively, they may come from comets that collide with the Earth and the release of water and gases on the surface.
However, they arrived, the position of the Earth in the solar system was fortuitous. Mercury and Venus are too close to the sun, so too hot for oceans to form (which evaporate only), while Mars is too far (just freeze liquid). Only on Earth were perfect conditions.
the atmosphere of the early Earth contained much more oxygen and was very different from what we have today. However, the life of the atmosphere and oceans has a foothold, and the first single-celled organisms evolved there are about 4 billion years.
Gradually, these algae have altered the composition of Earth’s atmosphere, munching their way through the carbon dioxide and water and release oxygen. In fact, around 2.5 billion years of large quantities of oxygen had accumulated in the atmosphere of Earth. The stage was set for complex life to evolve.
How Water Came into Earth?
Scientists can track the origin of water on Earth considered the ratio of two isotopes of hydrogen, or hydrogen versions with different numbers of neutrons, which occur in nature. One is an ordinary hydrogen atom, which has only one proton in the nucleus, and the other is deuterium, also known as hydrogen “heavy”, which has a proton and a neutron.
The ratio of deuterium to hydrogen in the oceans of the Earth seems to coincide with many asteroids, which are often rich in water and other elements such as carbon and nitrogen, instead of comets. (While asteroids are small rocky bodies orbiting the Sun, comets are sometimes called dirty snowballs body that releases gas and dust, and are believed to be remnants of the formation of the solar system frozen.)
The scientists also discovered opals in meteorites come from asteroids (which are pieces that probably knocked off asteroids). Since opals need water to form, this conclusion is another indication of the water from space rocks. These two pieces of evidence would support an origin of asteroids. In addition, the deuterium tends to rally further in the solar system that makes hydrogen, so that the water formed in the outer regions of the system would tend to be rich in deuterium.
And on top of that, internal rocky planets have relatively little water (relative to their mass) compared to the icy moons of Jupiter, Saturn, Uranus and Neptune, and even gas giants themselves. This would support the idea that within the system, the water evaporates, while in the external system, he did not. If the water evaporates on Earth, it would be necessary to replace elsewhere, and water-rich asteroids are abundant within the system.
More evidence comes from the Dawn spacecraft NASA launched in 2007, which found evidence of water on Ceres and Vesta, the two largest objects in the main asteroid belt between Mars and Jupiter.
The creation of a solar system
Astronomers believe they understand how our solar system formed have seen in other solar systems go through a similar process. is about 50 light years Beta Pictoris, a star in the middle of an infant solar system. images from the Hubble Space Telescope show a dust disk around the star, perhaps filled with budding planetesimals. Meanwhile, computer models of dust clouds, as it is believed to have given birth to our system, show that the gravitational forces almost always lead to a flat disc spinning powder lumps, from which the planets they can develop.