Expert: Jayendra Upadhye - 1/27/2008

Question
what is mean by supernova?
answer me in simple form....

Answer
Sarah, i will try.
A supernova is the death of star that was about 1.5 times heavier than our sun.
All stars burn hydrogen to generate presure to counter balance gravity that keeps on relentlessly trying to implode them.

After the hydrogen has been exhausted, the star contracts under gravity and the increased pressure (the surface being closer to the center, and amount of matter being the same, the pressure & temperature rises) causes it to burn helium, then carbon, oxygen etc. Each consequtive fuel is the "Ash" of the previous one.

All this continues till the star tries to fabricate something from iron burning, which is a "cooling" process rather than a "heating" one.
That actually cools the star, which further contracts it and all this extinguishes the nuclear fires in the core.

The star implodes and its core becomes a very very hard neutron star. The outlying layers fall inwards and rebound after hitting the hard neutron material of the core.

This rebounding shock is what we see as the supernova as it emerges or punches thru the infalling nmatter.
The energy is so tremendous that even elements beyond iron (on the periodic table) are synthesized.

Hope that suffcies.
Jayen