Mass before black hole.

[alpha2cen]

Let us think about big mass star.

If star mass is bigger than the limit, the star will become a black hole.

Then which phenomena will be happen before being a black hole?

.

----------------------------------------------------------------------------------------------->mass increase

planet------giant planet----------star----------------big star---------------black hole

.

Let us think it again related with mass from big star to black hole.

Big star is reduced it's mass rapidly by fusion reaction.

Very large amount of light energy is emitted, the light emitting force is bigger than gravity attraction force.

And, the more bigger mass star, it's light intensity is reduced and light frequency is increased.

If star weight is reached to the above limit, the star will be a black hole.

We represent the mass related to star phenomena like this.

 

(mass increase from big star to black hole)

Big star

.

. high energy emission, mass reduced rate is high, middle wave length light emission, gravity middle, fusion activity low

.

. middle energy emission, mass reduced rate is middle, short wave length light emission, gravity high, fusion activity middle

.

. very little energy emission, mass reduced rate is very slow, very short wave length light emission, gravity very high, fusion activity very high

.

V

Black hole

 

So, Has this black hole's inside very high fusion activity?

Edited February 10, 2011 by alpha2cen

[Spyman]

alpha2cen I think you need to improve on your english, it is very hard to understand what you are saying.

 

Wikipedia says that the fusion process ends before a core collapse in Type II supernovas:

 

Type II

 

Stars with at least nine solar masses of material evolve in a complex fashion. In the core of the star, hydrogen is fused into helium and the thermal energy released creates an outward pressure, which maintains the core in hydrostatic equilibrium and prevents collapse.

 

When the core's supply of hydrogen is exhausted, this outward pressure is no longer created. The core begins to collapse, causing a rise in temperature and pressure which becomes great enough to ignite the helium and start a helium-to-carbon fusion cycle, creating sufficient outward pressure to halt the collapse. The core expands and cools slightly, with a hydrogen-fusion outer layer, and a hotter, higher pressure, helium-fusion center. (Other elements such as magnesium, sulfur and calcium are also created and in some cases burned in these further reactions.)

 

This process repeats several times; each time the core collapses, and the collapse is halted by the ignition of a further process involving more massive nuclei and higher temperatures and pressures. Each layer is prevented from collapse by the heat and outward pressure of the fusion process in the next layer inward; each layer also burns hotter and quicker than the previous one—the final burn of silicon to iron consumes its fuel in just a few days at most. The star becomes layered like an onion, with the burning of more easily fused elements occurring in larger shells.

 

In the later stages increasingly heavier elements with higher binding energy undergo nuclear fusion. Fusion produces progressively less energy, and also at higher core energies photodisintegration and electron capture occur which cause further energy loss in the core, requiring a general acceleration of the fusion processes to maintain hydrostatic equilibrium. This escalation culminates with the production of nickel-56, which is unable to produce energy through fusion (but does produce iron-56 through radioactive decay). As a result, a nickel-iron core builds up that cannot produce further outward pressure on the scale needed to support the rest of the structure. It can only support the overlaying mass of the star through the degeneracy pressure of electrons in the core. If the star is sufficiently large, then the iron-nickel core will eventually exceed the Chandrasekhar limit (1.38 solar masses), at which point this mechanism catastrophically fails. The forces holding atomic nuclei apart in the innermost layer of the core suddenly give way, the core implodes due to its own mass, and no further fusion process is available to ignite and prevent collapse this time.

http://en.wikipedia.org/wiki/Supernova

[alpha2cen]

Wikipedia says that the fusion process ends before a core collapse in Type II supernovas:

 

 

I mean mass related black hole phenomena.

If we continuously added a mass to a very big star, what phenomena would be happen before being a black hole?

That is what I described.

Supernova is the only way to be a black hole?

Edited February 10, 2011 by alpha2cen

[Spyman]

I mean mass related black hole phenomena.

If we continuously added a mass to a very big star, what phenomena would be happen before being a black hole?

That is what I described.

Supernova is the only way to be a black hole?

That would depend on what kind of mass and how fast it is added, generally I think the star would burn more intense with more fuel.

 

In theory all that is needed is to accumulate enough mass inside the Schwarzschild radius and supernovas sems to be the common way of nature to achieve this.

[alpha2cen]

That would depend on what kind of mass and how fast it is added, generally I think the star would burn more intense with more fuel.

 

In theory all that is needed is to accumulate enough mass inside the Schwarzschild radius and supernovas sems to be the common way of nature to achieve this.

 

We can simply describe it like this.

Next figure show you mass related phenomena from big star to black hole.

.

big star------------------------------------->black hole

95%mass............................................100%mass

.

And this phenomena is represented with numbers for easy understanding.

 

Mass (%).......Related phenomena

99.990

99.995

99.997............ Small light emission

99.999

99.9995

99.99999........ Very very small light emission

100(Black hole) All emission stopped, No light absorption occurring

100.0001......... All emission stopped, very small light absorption rate

110................... No emission occur, very large light absorption rate

 

 

How much mass is the star light emitting rate very high?

Is the behavior of the star from 99% mass to 100%mass right?

Edited February 11, 2011 by alpha2cen

[steevey]

Let us think about big mass star.

If star mass is bigger than the limit, the star will become a black hole.

Then which phenomena will be happen before being a black hole?

.

----------------------------------------------------------------------------------------------->mass increase

planet------giant planet----------star----------------big star---------------black hole

.

Let us think it again related with mass from big star to black hole.

Big star is reduced it's mass rapidly by fusion reaction.

Very large amount of light energy is emitted, the light emitting force is bigger than gravity attraction force.

And, the more bigger mass star, it's light intensity is reduced and light frequency is increased.

If star weight is reached to the above limit, the star will be a black hole.

We represent the mass related to star phenomena like this.

 

(mass increase from big star to black hole)

Big star

.

. high energy emission, mass reduced rate is high, middle wave length light emission, gravity middle, fusion activity low

.

. middle energy emission, mass reduced rate is middle, short wave length light emission, gravity high, fusion activity middle

.

. very little energy emission, mass reduced rate is very slow, very short wave length light emission, gravity very high, fusion activity very high

.

V

Black hole

 

So, Has this black hole's inside very high fusion activity?

 

The light emitted is the result of the fact that the inner layers of the star is collapsing, but it produces a very big shock wave in the outer layers since its the resistance the electro-magnetic force, which by ratio is stronger than gravity, but the shockwave is traveling outward from the core and the gravity is too strong. At that point, if the star is massive enough, there is no known force which stops the star from collapsing to a point where it has an escape velocity greater than light. In the process of shrinking, matter sort of undergoes some phases. There's the phase where the atoms get very close to together and start to repel, and then, there's the point where they get even closer together so that electrons and protons fuse into neutrons, but gravity is too strong, so the neutrons compress into some new substance which we don't really know anything about, and continues shrinking into a singularity.

Edited February 11, 2011 by steevey

[alpha2cen]

I mean huge amount of mass and black hole relationship.

I know there are many paths exist to be a black hole.

But I 'd like to know the concrete concept about the path from huge mass star to black hole.

[Spyman]

We can simply describe it like this.

Next figure show you mass related phenomena from big star to black hole.

.

big star------------------------------------->black hole

95%mass............................................100%mass

.

And this phenomena is represented with numbers for easy understanding.

 

Mass (%).......Related phenomena

99.990

99.995

99.997............ Small light emission

99.999

99.9995

99.99999........ Very very small light emission

100(Black hole) All emission stopped, No light absorption occurring

100.0001......... All emission stopped, very small light absorption rate

110................... No emission occur, very large light absorption rate

 

 

How much mass is the star light emitting rate very high?

Is the behavior of the star from 99% mass to 100%mass right?

If you try to force a big star to become a Black Hole by feeding it with more fuel its increased gravity will cause the internal nuclear energy production to rise the outward pressure at a higher rate than the accumulating mass can hold it together. The star will grow rapidly until it sheds enough mass to become stable again.

 

The Eddington luminosity (also referred to as the Eddington limit) in a star is defined as the point where the gravitational force inwards equals the continuum radiation force outwards, assuming hydrostatic equilibrium and spherical symmetry. When exceeding the Eddington luminosity, a star would initiate a very intense continuum driven stellar wind from its outer layers.

http://en.wikipedia.org/wiki/Eddington_limit

 

Secondly a Black Hole is a Relativity phenomena and not like a Dark Star in Newton mechanics, photons are not increasingly limited by gravity to leave. Lightrays will be redshifted due to gravity but all photons emitted by a star on the limit to become a Black Hole can 'freely' continue outward. Once the Black Hole has formed no photons can longer pass from the inside of the Event Horizon to the outside and all photons moving towards the Event Horizon will be absorbed.

[alpha2cen]

Many stars are created and disappeared in the Universe.

And there are many cause to be a star.

Which one is the important factor of the stellar mass decision?

Is density of the interstellar dust cloud main factor?

[steevey]

Many stars are created and disappeared in the Universe.

And there are many cause to be a star.

Which one is the important factor of the stellar mass decision?

Is density of the interstellar dust cloud main factor?

 

The general idea is that stars begin to form when gas collapses from a shock wave. The resulting mass gradually draws more and more dust in. So I suppose it's mostly a matter of luck, and I guess if the gas isn't dense enough, its less likely to be a star forming region.

[alpha2cen]

The general idea is that stars begin to form when gas collapses from a shock wave.

 

To be a star, first interstellar dust density must be suitable to be a star. The interstellar dust transform into small particles to have gravity. AT this step, supernova explosion wind would be useful. If there were no external compression, it would be more time required.

[Spyman]

Many stars are created and disappeared in the Universe.

And there are many cause to be a star.

Which one is the important factor of the stellar mass decision?

Is density of the interstellar dust cloud main factor?

Cloud collapse

An interstellar gas cloud remains in hydrostatic equilibrium as long as the kinetic energy of the gas pressure is in balance with the potential energy of the internal gravitational force. Mathematically this is expressed using the virial theorem, which states that, to maintain equilibrium, the gravitational potential energy must equal twice the internal thermal energy. If a cloud is massive enough that the gas pressure is insufficient to support it, the cloud undergoes gravitational collapse. Once a region reaches a sufficient density of matter to satisfy the criteria for Jeans instability it begins to collapse under its own gravitational force. The mass above which a cloud undergoes collapse is called the Jeans mass. The Jeans mass depends on the temperature and density of the cloud, but is typically thousands to tens of thousands of solar masses. This coincides with the typical mass of an open cluster of stars, which is the end product of a collapsing cloud.

 

Triggered star formation

In triggered star formation, one of several events might occur to compress a molecular cloud and initiate its gravitational collapse.

 

1. Molecular clouds may collide with each other, or
   
2. a nearby supernova explosion can send shocked matter into the cloud at very high speeds.
   
3. galactic collisions can compress and agitate gas clouds in each galaxy by tidal forces. The latter mechanism may be responsible for the formation of globular clusters.
   
4. a strong wind through a collimated relativistic jet emits radio waves around the jet that agitates gas clouds, and
   
5. a weaker jet may trigger star formation when it collides with a cloud.
   

As it collapses, a molecular cloud breaks into smaller and smaller pieces in a hierarchical manner, until the fragments reach stellar mass. In each of these fragments, the collapsing gas radiates away the energy gained by the release of gravitational potential energy. As the density increases, the fragments become opaque and are thus less efficient at radiating away their energy. This raises the temperature of the cloud and inhibits further fragmentation. The fragments now condense into rotating spheres of gas that serve as stellar embryos.

 

Complicating this picture of a collapsing cloud are the effects of turbulence, macroscopic flows, rotation, magnetic fields and the cloud geometry. Both rotation and magnetic fields can hinder the collapse of a cloud. Turbulence is instrumental in causing fragmentation of the cloud, and on the smallest scales it promotes collapse.

 

Birth

Stellar evolution may begin with the gravitational collapse of a giant molecular cloud (GMC). Typical GMCs are roughly 100 light-years (lyr) (9.5 x 10¹⁴ km) across and contain up to 6,000,000 solar masses (1.2 x 10³⁷ kg). As it collapses, a GMC breaks into smaller and smaller pieces. In each of these fragments, the collapsing gas releases gravitational potential energy as heat. As its temperature and pressure increase, a fragment condenses into a rotating sphere of superhot gas known as a protostar.

 

http://en.wikipedia.org/wiki/Star-forming_region

[alpha2cen]

In the solar system,many comets move around the sun. I have heard some comets collide with the Jupiter. Then, are there any possibility the Jupiter to be a brown dwraf star latter?

[Spyman]

The Sun is estimated to contain ~99.8% of the total mass in our Solar System and Jupiter that has ~2.5 times of all the other planets mass put together takes up most of the rest. Since the lower limit for a Brown Dwarf is around 10 times the mass of Jupiter there are simply not enough comets.

 

[EDIT]

This has nothing to do with the thread just testing the editing expiring time.

Edited March 8, 2011 by Spyman