Two Types of Supernovae
A supernova is an explosion of a massive giant star.
This is a vast explosion where the whole star is blown up. It can shine up to 10 billion stars bright, making them extremely bright. Supernovae are so faint that it is hard for even the largest telescopes to see them. This is because they are not observed to be in elliptical galaxies.
Supernovae are classified as type I or II depending on their shape of curve of light and the mechanism that causes them to explode.
Supernovae type I involves two stars with a different mass composition. The two stars are close together and they both fuse hydrogen into helium. The bigger more massive star converts its hydrogen into helium more rapidly than the smaller star. After all of the hydrogen is converted to helium, it swells into a red giant and sheds its outer layers onto the smaller star.
The red giant then turns into a white dwarf which consists of mostly carbon and oxygen. Meanwhile the smaller star has gained mass and formed into a red giant. This starts the same process that the first red giant star went through. Now with the second star a red giant it dumps its outer layer onto the white dwarf. When the white dwarf reaches a critical mass of 1.4 solar masses, the temperature is increased to an incredible 4 billion degrees. The carbon ignites, detonating the star as a supernova, which in turn shoots the other star out of the two star system.
Type II supernovae is a single star implosion-explosion event. The star is usually more than ten times the mass of our sun and peaks at about 1 billion solar luminosities. A red giant is formed from all of the elements fusing together...