Stars of the Universe
By: Janna • Essay • 492 Words • February 26, 2010 • 801 Views
Join now to read essay Stars of the Universe
The Big Bang:
The Big Bang theory is an effort to explain how the universe was made. Our universe is thought to have begun as small, hot and dense. After the big bang theory the universe expanded and cooled, going from very small, and hot, to the size and temperature of our current universe. It continues to expand and cool, and we are inside of it. Some misconceptions to the Big Bang theory is that we imagine a giant explosion, however there was no explosion there was an expansion. So instead of imagining a balloon popping and releasing its contents, imagine a balloon expanding.
Inside Stars:
After the Big Bang it took 300,000 years for stable hydrogen and helium atoms to form. Eventually these atoms began to clump together into gas clouds. Over the course of time (300 million years) these clouds grew, they attracted more and more atoms and so became dense and hot. The centers of these clouds became so hot and dense that they exploded in huge nuclear reactions. Hydrogen atoms began to fuse together and the clouds were transformed into blazing balls of fire. The first stars were born.
Types Of Stars:
DWARFS
Our sun is a dwarf star, throughout their lives, stars go through many phases of expansion and contraction. When they are a normal size for their weight they are called 'dwarfs'.
➩Red dwarfs are failed stars that never heated up enough to explode into a normal star
➩White dwarfs are dying stars that are slowly burning away the last of their fuel. The term 'white' is a bit of a misnomer though, as they range in color from hot white through to cool red. Eventually however, they will all become black dwarfs - non-luminous dead stars.
SUPERNOVAE
When an old massive star has run out of all its fuel, it collapses in an explosion called a supernova. This releases