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What are the 8 planets in the solar system?
History of the atoms in your body
The universe began in the big bang. By the time the universe was a few minutes old, the proton
neutrons, and electrons in your body had come into existence. You are made of very old matter.
Although those particles formed quickly, they were not linked together to form many of the
atom that are common today. The matter in the early universe was about 75% hydrogen(by mass) and
helium. Our galaxy contains at least 100 billion stars, of which the sun is one. Astronomers have a variet
of evidence that the sun from a cloud of gas and dust about 5 billion years ago and the atom in your bod
were part of that cloud. The stories of how the cloud gave birth to the planet and how the atoms in you
body found their way onto earth and into you make up the story. Geologist Preston Cloud remarked
"stars have died that we might live"
The Solar Nebula Theory
Over the last two centuries, astronomers have proposed two kinds of hypothesis for the origin
the planets in our solar system.
Catastrophic hypothesis proposed that the planets formed from some improbable event such as to
collision of the sun and another star.
Fynlutionary hynnthesis proposed that the planets formed gradually and naturally as the sun for​