What else if not a supernova?

Question

I am currently taking Astr.100L. In a section I was reading it says a star may explode as a supernova. If it does not explode as a supernova, then what else could it be? Thank you.

Answer 1

A white Dwarft is the other finalle for a star. and sometimes even a black hole.

Answer 2

Stars may end their lives in a number of different ways. Those stars that are massive enough can indeed die in the supernova explosion. Most stars, like our own sun, don't have enough mass and "quietly" end their lives as tiny white dwarf stars.

Answer 3

At some point all of the nuclear fuel in the star has been exhausted. A greater part of the hydrogen has been converted into helium and most of helium has been converted into carbon and oxygen. What happens now to the star depends on the mass of the star.

SMALL STARS - Smaller stars, about 4 masses of our Sun or less, cool down. Given time, the outer layers of the star become cool enough to leave the plasma state. The atoms reverse to their neutral state and capture electrons. The capture of electrons accelerates the expansion of the outer layers, which causes more atoms to leave the plasma state.The envelope of the star becomes finally a transparent and extensive shell of atoms; this shell can only be seen from the side from very long distances, thus giving the surroundings of the star a peculiar appearance of a luminous ring. Once upon a time, astronomers believed those rings were the first stage of formation of planetary systems; because of that the rings were called "planetary nebulae" . We know today that there is no connection between the planetary nebulae and planetary systems, but the name remained.The only remnant of the star is now the core of the star and it is a tiny and not very bright object in the middle of the nebula. In the beginning the core of the star is still glowing with a white glow, dissipating the heat from the nuclear fires, now extinct. It is called a"white dwarf" . A white dwarf weighs much less that the original star, for example a star four times heavier than the mass of our Sun gives origin to a white dwarf having 1½ of the mass of our Sun.

MEDIUM STARS - Larger stars, between 4 and 8 masses of our Sun, encounter a more violent fate. The stopping of nuclear reactions makes them collapse more rapidly and more violently than the small stars. The core of the star consists now of solid carbon, which is not burning. However, the contraction of the star generates enormous amounts of heat. At the point when the temperature of the core reaches 600 000 000 K, the carbon starts a nuclear reaction, generating neon, helium, magnesium and some other elements.The star explodes in a SUPER-NOVA. The explosion is so bright that a super-nova can even be seen on the Earth in daylight. The explosion shatters the star and may be so violent that it disperses all of the material of the star in outer space.

LARGE STARS - Really large stars, with masses greater than 8 masses of Sun, do not become a super-nova at this point of time. The stopping of nuclear reactions causes contraction, like for the smaller stars. But the core of the largest stars does never become as dense as the core of medium sized stars. This is probably caused by the intense radiation inside the core of the largest stars, giving an abundance of highly energetic photons that drive out matter from the center of the star.When carbon and oxygen are exhausted, the star cools down and shrinks again, which again heats the core of the star to higher temperatures. A star at this stage of life can produce elements no heavier than iron. The nuclear reaction comes to an end with iron. Iron does not engage in nuclear fusion. Fusion of elements less heavy than iron releases energy, while fusion of iron and elements heavier than iron consumes energy.The creation of iron extinguishes the nuclear fire inside the star. The star shrinks for the last time. The iron core of the star absorbs most of the heat generated by the contraction of the star, which accelerates the contraction even more. When the temperature inside the core reaches trillions of degrees and the neighboring atomic nuclei touch each other, there can be no more contraction. Instead, the star rebounds in a great explosion. This explosion is also called a SUPER-NOVA and may be as spectacular as for the medium sized stars. The star is billions times brighter than any time previously and it may even be as bright as an entire galaxy.

BLACK DWARFS - A white dwarf cools down slowly. The colour of the glow of the surface changes from white to yellow, to orange and red. Finally the remnant of the star becomes a cold dark lump of matter - the black dwarf. The black dwarf has the size of our planet and a gravity that is millions of times higher than the gravity we experience on the Earth.

The black dwarf is simply a quiet, desolate and dead remnant of a star, moving forever through the cold Universe.

BLACK HOLES - A very massive star core, remnant of a super-nova explosion, can exert such a tremendous gravitational force that not only solid objects, atoms cannot escape from the star's surface. Also light "falls down" to the surface of the star. That kind of object is called a "black hole" .The matter within the black hole probably shrinks to smaller and smaller volumes all the time. The star shrinks to a few kilometres, then a few centimetres and - finally - to a "singularity", which is one single point in space. Even though the matter inside the black hole collapses into size

Answer 4

Stars can explode as a nova, which is simply a collapsing or collapsed star that experiences runaway nuclear fusion on the surface. Novae are really more of an extreme variable star than an exploding star because the main body of the star is unaffected by the outburst. Only the atmosphere and accumulated material from a companion star gets blown back into space. As such, even a very powerful nova outburst is some 50,000 times less powerful than an average core-collapse supernova.

Answer 5

A nova.

Answer 6

Actually, hypernovas are when a star goes supernova and sets off a gamma ray burst. It could end up as that. But really, it is just as a supernova, GRB or if it doesn't fully develop, it could just sit there as a brown dwarf. However, I'm just a sophmore in High School.

Answer 7

There are hypernovas, which are much more massive.

Answer 8

Stars essentially have two possible life-ending events, and 3 possible outcomes...

Small stars, like our sun, will run out of their fuel (hydrogen), and swell up, becoming red giants.  Our sun will swell up to engulf the first 3 planets, and that will be the end of Earth.

This red giant will slough off it's outter layers, and all that will be left is a small core, about the size of Earth or a little larger, that will glow white for a few million years, but gradually cool to yellow, then red, then finally to black.

Stars with at least 8 to 10 solar masses or larger have another possible outcome.  Being more massive, they'll begin to burn the helium created in their cores into heavier elements - Carbon, Calcium, and so forth, up to the element of Iron.  A star can't "burn" iron and still create energy - so, when this massive star runs out of fuel, it collapses.  It falls in on itself, creating a huge overpressure around its core, and this triggers a *huge* explosion.  

Much of the star's outter layers are blown out and away, while the core is compressed.  

Now, the compression that occurs depends on how massive the star was.  In some cases, the atoms in the core are crushed - the electrons are literally crushed to merge with the protons, forming a mass of nothing but neutrons.  You know how an atom is mostly empty space?  In a neutron mass, there is *no* empty space - the core is crushed down to about 12 to 15 miles across, and is more massive than our sun.

Compression doesn't have to stop there.  If the implosion is strong enough, the core will *continue* to compress, until finally, the fabric of our universe can't support it anymore - there's too great a mass in too small a volume of space - and a black hole forms.  

Answer 9

a white dwarf