myth+and+belief+-+Big+Bang+Theory

=Lesson - Big Bang Theory=

Astronomy: it is the scientific study of the universe and celestial bodies (planets, stars, comets…etc), especially their positions and movements Astronomy is based on data, facts, observations and experiments

Big Bang Theory: it is a commonly accepted theory about how the universe began
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Big Bang Theory: it is a commonly accepted theory about how the universe began Our Universe burst into sudden existence in a massive explosion/expansion called the Big Bang The Universe is still changing and evolving. It occurred around 13.7 billion years ago All matter and radiation in the universe started out in an extremely hot, dense state similar to a fireball. From this state, the universe expanded rapidly. It was the beginning of time and space as we know it. Matter and radiation from the fireball expanded and cooled within seconds, protons, neutrons and electrons formed. Minutes later, Hydrogen and other trace elements were created. Millions and millions of years later, as matter and radiation separated, galaxies and stars started to form. The Universe continues to expanded even today and new stars are forming. The universe is made up of approximately 74% Hydrogen, 24% Helium and other trace elements

One result of the big bang was the formation of the four basic forces in the universe. The forces are:
 * Electromagnetism
 * Strong nuclear force
 * Weak nuclear force
 * Gravity


 * [[image:http://3.bp.blogspot.com/_2DA2q19ANzY/SazQ-i8GZhI/AAAAAAAAADc/bHendRYH6rQ/s400/Big+Bang+Theory.jpg width="391" height="362"]] || [[image:http://3.bp.blogspot.com/_SxFCd2uFUAc/SV-Rw5Q-i3I/AAAAAAAAAZs/SQjfkzuaGvc/s400/Big+Bang+04.bmp]] ||
 * [[image:http://static.howstuffworks.com/gif/big-bang-8.jpg width="400" height="333"]] ||

The "Big Bang Theory" and the Science Behind the Cosmos
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 * Singularity - a small but extremely dense dot in space
 * An event triggered the explosion/expansion of the universe
 * All matter in the universe was created at the same time, but has expanded
 * Universe is still expanding today
 * 0 years to 380,000 years - universe too hot to support matter
 * Universe cooled after 380,000 years and matter formed
 * Hydrogen formed
 * Gravity brought hydrogen together
 * When enough Hydrogen fused together Super - Hydrogen Stars formed (100x larger than our sun)
 * These stars had short lives - explode in hypernova, gave birth to Galaxies and Solar Systems
 * All elements for life were formed in stars