In what circumstances does a Supernova occur??

Question

Okay so the title says it and...just how powerful is a supernova??

Answer 1

A supernova (plural: supernovae or supernovas) is a stellar explosion that creates an extremely luminous object that is initially made of plasma—an ionized form of matter. A supernova may briefly out-shine its entire host galaxy before fading from view over several weeks or months. During this brief period of time, the supernova radiates as much energy as the Sun would emit over about 10 billion years. The explosion expels much or all of a star's material at a velocity of up to a tenth the speed of light, driving a shock wave into the surrounding interstellar gas. This shock wave sweeps up an expanding shell of gas and dust called a supernova remnant.

There are several types of supernovae and at least two possible routes to their formation. A massive star may cease to generate energy from the nuclear fusion of atoms in its core, and collapse under the force of its own gravity to form a neutron star or black hole. Alternatively, a white dwarf star may accumulate material from a companion star (either through accretion or a collision) until it nears the Chandrasekhar limit of roughly 1.44 times the mass of the Sun, at which point it undergoes runaway nuclear fusion in its interior, completely disrupting the star. This second type of supernova is distinct from a surface thermonuclear explosion on a white dwarf, which is called a nova. Solitary stars with a mass below approximately 8 solar masses, such as the Sun itself, evolve into white dwarfs without ever becoming supernovae.

On average, supernovae occur about once every 50 years in a galaxy the size of the Milky Way and play a significant role in enriching the interstellar medium with heavy elements. Furthermore, the expanding shock waves from supernova explosions can trigger the formation of new stars.

"Nova" is Latin for "new", referring to what appears to be a very bright new star shining in the celestial sphere; the prefix "super" distinguishes supernovae from ordinary novae, which also involve a star increasing in brightness, though to a lesser extent and through a different mechanism.

Answer 2

One of the most energetic explosive events known is a supernova. These occur at the end of a star's lifetime, when its nuclear fuel is exhausted and it is no longer supported by the release of nuclear energy. If the star is particularly massive, then its core will collapse and in so doing will release a huge amount of energy. This will cause a blast wave that ejects the star's envelope into interstellar space. The result of the collapse may be, in some cases, a rapidly rotating neutron star that can be observed many years later as a radio pulsar.

How big can a supernova get? Beyond the "big explosions are cool" aspect, the topic has some important scientific implications. Early in the life of the universe, when matter was more densely packed, it's believed that extremely large stars formed and exploded at a rapid clip. This both influenced the dynamics of the early galaxies and led to the distribution of heavier elements that have allowed things like our solar system to form. So, understanding the explosions of the earliest stars can help us comprehend the evolution of the universe.

Answer 3

Supernovae are divided into two basic physical types:

Type Ia. These result in some binary star systems in which a carbon-oxygen white dwarf is accreting matter from a companion. (What kind of companion star is best suited to produce Type Ia supernovae is hotly debated.) In a popular scenario, so much mass piles up on the white dwarf that its core reaches a critical density of 2 x 109 g/cm3. This is enough to result in an uncontrolled fusion of carbon and oxygen, thus detonating the star.

Type II. These supernovae occur at the end of a massive star's lifetime, when its nuclear fuel is exhausted and it is no longer supported by the release of nuclear energy. If the star's iron core is massive enough then it will collapse and become a supernova.

Answer 4

How Does A Supernova Occur

Answer 5

When a massive star produces element higher than hydrogen,helium etc in it's fusion furnace then exhausts all it's fuel it collapses and then rebounds in a massive explosion.
The rocky debris is ejected in thousands of cone or cigar shaped packages that crash into the surrounding hydrogen field an spawn secondary stars and planets like our solar system.
The most prominent one was 1987A,a blue super giant that exploded in the large Magellanic cloud some 170,000 light years away,it was pretty bright but in galaxies even super novas are pretty small.

Answer 6

At the end of the life of a giant star it collapses inward at near the speed of light, the great mass is crushed to a very small volume and there is a tremendous rise in temperature creating the elements that are heavier than iron, a rrebound effect takes place and the matter of the sun is thrown into space in one of the most violent reactions that takes place in the universe, the light created is greater than the combined light of millions of ordinary stars.

Answer 7

stars, , which are more massive than the Sun, become much larger, and any planets surrounding those stars would almost certainly be consumed, or, when the star ends its life, in a supernova explosion, be vaporized and blasted to smithereens.
Finally, after the stars die, they become very small. Stars like the Sun, and less massive stars, become white dwarfs, stars a few thousands of miles in diameter. More massive stars become either neutron stars, which are only a few miles in diameter, or singularities, which have no size at all, but are surrounded by small regions, called black holes, where gravity is so large that nothing, including light, can escape. The sizes of such black holes are a few miles or tens of miles in diameter, depending upon the mass of the singularity hidden inside them.
So, to summarize the answer to your question, the sizes of stars do depend upon their ages. They tend to be fairly large when forming, and very large when dying, of in-between size when Main Sequence stars, and very small when they finally die. But their sizes also depend upon how massive they are, more massive stars being larger at every stage of their formation, life and dying, and incredibly tiny when finally dead, while less massive stars are much smaller during their formation, life and dying, but only fairly small, when they finally die.

Answer 8

When a giant star runs out of energy and clapsese on itself and makes a giant explosion

Answer 9

When a star of right mass dies. They are very powerful.