1supernovae

**General Topic ** **-->** The Life Cycle Of A Star


 * Specific Topic ** **-->** Supernovae

Stars originate in the form of nebulae, which are huge interstellar clouds of dust and gas. Once they collapse under their own gravitational force they create protostars. As a star grows older it will turn into a main sequence star and become larger with time. Depending on its initial size and mass, a star may or may not be large enough to become a //supernova//.



A supernova is the most powerful of all stellar explosions. They occur when the nuclear fuel of a star is burnt out, or used up. In layman's terms a supernova would be the "death" of the main sequence star. The energy produced by an explosion of a red supergiant may be up to as much energy as the sun produces in about 10 billion years! Imagine the amount of energy the sun has provided the Earth its entire lifetime exploding all at once! Supernovae do not occur that frequently. In fact the most recent supernova known to explode in The Milky Way Galaxy was about 140 years ago. There are an estimated three supernova per century predicted to occur in our galaxy. The photo above is an image of Kepler's supernova, which he observed in 1604. He documented it to be brighter than both Mars and Jupiter to the naked eye!


 * 1) A Type I supernova is when a white dwarf with 1.4 solar masses or less has a companion star (binary star system) that will transer its matter to the white dwarf into something called an accretion disk. Once its mass is pushed over the 1.4 limit a huge star explosion will occur.
 * 2) A Type II supernova is when a massive star runs out of energy and collapses in on itself creating a neutron star. Astronomers can tell the type of supernova by how bright they are on the spectrum.

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 * Quick Facts:
 * A supernova will last for up to a week and can be as bright as a galaxy of 100 billion ordinary stars.
 * Humans are made up of the same elements found in a supernova.
 * A supernova of the sun will probably destroy our solar system.
 * When the core of a star is greater than 5 solar masses and it explodes it will become a black hole.
 * Supernovae create elements heavier than iron.


 * Links For Additional Information: **
 * 1) [|Nasa --> Supernovae]
 * 2) [|The Supernova]
 * 3) [|The Life Cycle Of A Star]


 * Bibliographical Information: **







