About 13,8 billion years ago, all matter and energy of the universe was concentrated in an infinitely small space, which we call it uniqueness.

And suddenly this uniqueness began to expand at incredibly high speed, creating the universe we know today.

Big Bang

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In those early stages of the existence of the universe, the elements of existence were the hydrogen(H) and the helium(He),
which are the most simple and light elements.
With hydrogen as the first fuel, the first stars began to form, the first suns.
And many such stars together formed the galaxies.
Our galaxy is one of these first galaxies,a large fiery galaxy, which at that time was of no particular interest in terms of biology.
But inside these stars something very impressive happened:

Because of the very high temperatures and pressures inside the stars, these simple elements began to transform into more complex, heavier elements, and so all the other elements we know, such as coal, oxygen, nitrogen and the heaviest metals, which are necessary for life to exist.
And when these stars reached the end of their lives, they had somehow lost the outer casing, if they were small stars,
or if they were big stars they did these supernova explosions, scattering all the new heavy elements to the galaxy, which had been created within them.
And so our galaxy slowly grew enriched...

4,6 billion years ago, in a common corner of our galaxy, our solar system began to form, that is, the sun and the planets we know, and the planet we inhabit, the Earth.
Earth was originally a planet that was not ideal for life. The planet was scorching, the temperatures were too high. The Earth's crust sterilization took place 4,4 billion years ago.

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From then on, life did't take long to appear. The first forms of life emerged 3,5-4 billion years ago. We are talking about simple life forms, unicellular photosynthetic forms of life.

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The most complex forms of life, the multicellular, have lasted long enough to appear, and they are placed about 1,5 billion years ago. And after appeared all these species we have known.
The most famous ecosystem of prehistoric life is the dinosaur era (250-66 million years ago)

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The dinosaurs suddenly disappeared after the fall of a major meteorite on Earth, something that happened 66 million years ago. Such disasters had become many in the past of the Earth.
We know at least 10 major disasters, of which 5 have led to mass extinctions of species.
The last such disappearance is the disappearance of dinosaurs.
Thanks to the extinction of the dinosaurs, some other animals began to grow ....
Mammals, which, after many millions of years, led to primates mammals and a very special species somewhere in Africa that could use tools and communicate with speech. This was the human species Homo Sapiens-Sapiens (200.000 years ago).

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It is remarkable that while we have been there for so many years on the planet, over the past 400 years, we have come to understand what is happening in the universe...

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Our knowledge has expanded a lot, but with this knowledge some of our existential problems have intensified ...
Within the universe there are 2 trillion galaxies, each of which has an average of 100 billion solar systems, namely suns with planets around them, and that's only 5% of the matter and energy of the universe we know.
The other 95% is dark matter and dark energy, we do not know exactly what it is. There is also a limit on how far we can see. We only see the observable universe, because there are areas of the universe that are being removed from us at a speed greater than the speed of light.

Thus we understand that we are not the center of the universe, our value is very small in terms of space and time. The age of the universe is 13,8 billion years, while the average human life in a developed society is about 80 years.
We look like a spark of a life and then we are lost.

Human is hopelessly small in front of the universe.

This is the first awareness that astrophysics offers us.

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So, through this historic turn of 13,8 billion years, we conclude that excluding hydrogen, all the other materials in our body have been created inside the stars.
These stars had to die to get the materials to our bodies.

We are children of stars...

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Hydrogen, which existed at the beginning of the universe, through natural laws and through 13,8 billion years of astral and biological evolution, eventually led to a conscious being.

We are conscious material and now we are wondering why it exists.

We are the matter ,now studying the matter.

Carl Sagan:

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Our existence resembles a miracle, as everything that should happen ,happened at the right time and with the specific order of events for life to exist. Something that we do not appreciate in our everyday life.
We also think that our life's journey will eventually end, but we must feel fortunate that a little moment we have also been in this universe.

thanks for reading!
@mariossap