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Supernovae

Supernovae is an explosion of star. The star that massive 10 or 100 more time massive than sun can go into end as Supernovae. Its a condition of the exploding star with increasing of the luminosity of star millions of time higher than the normal.

Supernova comes from the Latin word "Nova" that means New star.

Scientists found there have two types of supernova. Type one supernova and type two supernova. The basic difference of type one and type two supernova is in these spectra. Where type one supernova do not have any hydrogen line in its spectra there type two supernova have.
A supernova can happen in different way. Sometimes scientists classifies supernova on the basis of happening mechanism of supernova.

When a white dwarf star starts to fuse of carbon and oxygen in its entire body detonation mechanism of supernovae happens.

Another types of supernovae is caused by merging of two neutron stars or merging of massive black hole and neutron stars. The cause of happening of supernova during merging is that loss of orbital energy due to gravitational wave radiation that results as producing of GRB with fireball and afterglow.