Super+Nova


 * Supernovas **
 * By:Nicole & Eric **

Supernova's are exploding stars in outter space. They're brightness can become billions of times more than that of the sun, at their full brightness they could outshine an entire galaxy. Large dust and gas clouds from the explosion are thrown into outter space, and the mass of the material can be 10 times more than the suns mass. There are two types of supernovas. Nova means new.

There is type 1 and type 2 supernovas. Type 1 occurs in binaries, which are two stars that are close together and orbit about eachother. One star is a small dense star called a white dwarf. If the two stars are close enough to eachother the gravitational pull of the smaller star draws mass from the larger star. A white dwarf star can reach a mass about 1.4 times that of the sun, it collapses then explodes This is a type 1 supernova.

Astronomers use type l supernovas to measure things like the scale of the universe and how it is expanding. If all type l supernovas have the same brightness, then the dimmer one appears, the further away it must be. By using a precise brightness-distance relation astronomers are able to estimate the expansion of the universe and also the geometry of the universe.A type 2 supernova is from the death of a single star much bigger than the sun. When the star burns out its core quickly collapses. Energy is released in the form of neutrinos and elctromagnetic radiation. This energy causes the star to explode into a supernova.

This is a type 2 supernova.

Most supernovas reach their maximum brightness a few days after they explode, then shine intensely for several weeks. Some fade within months, and others of a period of years. They also differ in the amount and type of material they throw into space.

Supernovas leave behind different materials. After some supernova explosions, there remains a small, dense star made up mainly of neutrons or maybe of elementary particles called quarks. This star is called a neutron star. Rapidly rotating, highly magnetized neutron stars are called pulsars. After other explosions, an invisible object called a black hole may be left behind. A black hole has such powerful gravitational force that not even light can escape it. In some cases, there is nothing left behind from the explosion.

Scientists believe that supernovas created all the heavier elements, such as iron, gold, and uranium, that are found on earth and have been found outside the solar system. Also, there is evidence that some high energy cosmic rays come from supernovas. Although many supernovas have been seen in nearby galaxies, supernova explosions are pretty rare events in our Galaxy, they happen about once a century. The last nearby supernova explosion occurred in 1680, before then the two most recent supernova explosions were observed by astronomers Tycho and Kepler in 1572 and 1604.

There are many stars in our galaxy, which will go supernova, maybe not in our lifetime but millions of years from now. That is why astronomers are working so hard today to figure out the mysteries behind their cause and the effect they have upon space and other stars in the space. They may be quite a while off coming to this conclusion but with the computer technology today, the telescope and the understanding of space, it will only be a matter of time.