Reinforcing Theoretical Mass Limit for Stars

[Dragon Star]

The small open star cluster Pismis 24 lies in the core of the large emission nebula NGC 6357 in Sagittarius, about 8,000 light-years away from Earth. Some of the stars in this cluster are extremely massive and emit intense ultraviolet radiation.

The brightest object in the picture is designated Pismis 24-1. It was once thought to weigh as much as 200 to 300 solar masses. This would not only have made it by far the most massive known star in the galaxy, but would have put it considerably above the currently believed upper mass limit of about 150 solar masses for individual stars.

However, Hubble Space Telescope high-resolution images of the star show that it is really two stars orbiting one another. They are estimated to each be 100 solar masses.

http://www.astronomy.com/asy/default.aspx?c=a&id=4795

Lots of scientists just breathed a sigh of relief. This was a huge puzzle to scientists for some time now, and it looks like they were right.

Oh, and the image at the bottom of the page is fantastic.

[Blue Fire]

Here's the link to the APOD pic and story on NGC 6357 and Pismis 24 star cluster. The pic there is oriented differently than the one at the bottom of the page that Dragon Star posted. And it's an impressive shot from any angle!

A question I have is how many solar masses make a star big enough to go black hole?

[Dragon Star]

Originally Posted by Blue Fire

Here's the link to the APOD pic and story on NGC 6357 and Pismis 24 star cluster. The pic there is oriented differently than the one at the bottom of the page that Dragon Star posted. And it's an impressive shot from any angle!

A question I have is how many solar masses make a star big enough to go black hole?

3-5 solar masses for the present universe, at which point the star can no longer sufficiently support it's self from rebound.

[Diana]

I think, (if I remember right) that the mass limit is somewhere around 150 solar masses. But not all stars that exeed mass limit will become black holes.

The Chandra limit is the maximum mass of a white dwarf star. At the end of a star's life, when most of its energy is gone, it begins to collapse. If the mass of the star is below the Chandra limit, the star becomes a white dwarf and continues to burn. If it exceeds the limit, its gravity will overcome pressure inside the star, and it will continue to collapse into a neutron star or a black hole.


The article that Dragon Star provided mentions this:

Although the stars are still among the heaviest known, the mass limit has not been broken thanks to the multiplicity of the system.....

Diana

[Diana]

Well, Dragon Star if I am wrong please let me know.....

[Dragon Star]

You are actually, I think you got 150 for the maximum predicted mass that a Star can sufficiently support it's self. (the opposite of becoming a black hole ) Though the largest Star known is thought to have a mass of just over 100 solar masses.

A quantitative analysis of this idea led to the prediction that a stellar remnant above about three to five times the mass of the Sun (the Tolman-Oppenheimer-Volkoff limit) would be unable to support itself as a neutron star via degeneracy pressure, and would inevitably collapse into a black hole.

-Wiki.

[Blue Fire]

Originally Posted by Dragon Star

You are actually, I think you got 150 for the maximum predicted mass that a Star can sufficiently support it's self. (the opposite of becoming a black hole ) Though the largest Star known is thought to have a mass of just over 100 solar masses.
Quote:

-Wiki.

So, the key words here for me seem to be Stellar Remnant, and 3-5 solar masses would be the lower limit for a star in the condition of being a stellar remnant for collapsing to a black hole. Right? If so, then stars of much greater mass can exist without ever becoming a black hole simply because their particular life cycle would be different and result in a supernova or something else aside from a black hole?

[Dragon Star]

Originally Posted by Blue Fire

So, the key words here for me seem to be Stellar Remnant, and 3-5 solar masses would be the lower limit for a star in the condition of being a stellar remnant for collapsing to a black hole. Right? If so, then stars of much greater mass can exist without ever becoming a black hole simply because their particular life cycle would be different and result in a supernova or something else aside from a black hole?

Stellar Remnant is referencing what is left after a star has gone through it's cycle. Stars lose a lot of mass throughout their life, (especially the end) so that's probably why they removed the generalization. There is only two ways I know of that a star exceeding the limit does not become a Black Hole.

A. It's part of a Binary system, as is getting absorbed by the parasitic Star.

B. The star is forced to exceed it's Roche Limit by a Black Hole or Neutron Star.

[Diana]

Originally Posted by Dragon Star

You are actually, I think you got 150 for the maximum predicted mass that a Star can sufficiently support it's self. (the opposite of becoming a black hole ) Though the largest Star known is thought to have a mass of just over 100 solar masses.

-Wiki.