What Are Novas?

Novas are an explosion from the surface of a white dwarf, a nova happens the dense core of a normal star steals gas from a companion star. They are nuclear explosions, and are not to be confused with other brightening phenomena such as supernovae. When it gets enough gas from the other star it explodes. There are a lot of different novas, but the ones we'll be talking about are supernovae, hyper-nova, and kilo-nova.

A supernova is still a nova, it's just more energetic and violent. Supernova's can shine as brightly as a galaxy or a billion normal stars. They are divided into two groups, Type 1 and Type 2. Type 1 supernovae make runaway thermonuclear explosions, that blast stars to bits. Those are the brightest, and can be used as a unit of measurement to measure other galaxies. Type 2 supernovae are the final stages in a stars life, they can get up to 10 times more massive then our sun. This is the point where the star can no longer produce nuclear energy. Without that it has no outward pressure, so gravity takes over and makes the star collapse forming a black hole, or a neutron star. So the star blast into space at several percent of the speed of light.

A hyper-nova is a very energetic supernova thought to result from an extreme core-collapse scenario. It has a luminosity 10 or more times higher than that of standard supernovae. In order for a hyper-nova to happen it has to be a massive star that collapses, forming a black hole. The collapse happens so quickly that the star explodes by very aggressive winds that blow of the accretion disk. The luminosity of the hyper-nova is powered by radioactive decay of Ni56. Scientist also speculate that the formation of hyper-novas also contribute to gamma ray burst, but is often debated.

A kilo-nova is a transient astronomical event that occurs in a compact binary system when two neutron stars or a neutron star and a black hole merge into each other. In case you don't know what a neutron star is, it is basically a dying star that collapsed and had a supernova explosion, the star is insufficiently massive to produce a black hole. Now when two neutron stars start to collide, they start spinning around each other. While they are spinning they create spirals around them. They end up spinning closer and closer towards each other and at a faster rate. They start spinning until they collide creating a kilo-nova. The luminosity from kilo-novas can be seen from earth with a telescope and can last a very long time.

There are a lot of different novas, but the ones we'll be talking about are supernovae, hyper-nova, and kilo-nova. A supernova is still a nova,it's just more energetic and violent. Supernova's can shine as brightly as a galaxy or a billion normal stars. Those are the brightest, and can be used as a unit of measurement to measure other galaxies.

Without that it has no outward pressure, so gravity takes over and makes the star collapse forming a black hole, or a neutron star. A hyper-nova is a very energetic supernova thought to result from an extreme core-collapse scenario. Now when two neutron stars start to collide, they start spinning around each other. While they are spinning they create spirals around them.

They end up spinning closer and closer towards each other and at a faster rate. They start spinning until they collide creating a kilo-nova.The luminosity from kilo-novas can be seen from earth with a telescope and can last a very long time.