How massive can a star be?

[Glitch]

Originally Posted by PITTSTON2SARASOTA

200 Solar Masses for a stable star......is the absolute maximum I'm aware of.....(anything much heavier....about 250 Solar Masses quickly collapses into a Black Hole)

Antimatter-Powered Supernovae: Scientific American

How Large Stars Die [Animation]: Scientific American

Except that R136a1 is already 265 solar masses, and they suspect it was once 320 solar masses, gradually losing 55 solar masses over time. Furthermore, they do not collapse into a black hole. Stars above 130 solar masses die in a pair-instability supernova. The free positrons and electrons, combined with energetic gamma rays, actually reduces thermal pressure at the core, and the super massive star explodes leaving nothing behind.

[FredNotBob]

The the best of my (admittedly limited) knowledge, the 'upper limit' to a star's mass would be when it's sufficiently massive to collapse into a singularity.

A singularity, for those not up on the science, is a superdense 'point' in spacetime where mass and energy are theoretically infinite (theoretically, because all we know for sure is that it outstrips any method we currently know of to measure it).

[Glitch]

Astronomers crack mystery of the "monster stars"

...

“Imagine two bulky stars closely circling each other but where the duo gets pulled apart by the gravitational attraction from their neighboring stars,” Banerjee continued. “If their initially circular orbit is stretched enough, then the stars crash into each other as they pass and make a single ultramassive star.”

“Although extremely complicated physics is involved when two very massive stars collide, we still find it quite convincing that this explains the monster stars seen in the Tarantula,” Banerjee concluded.


Source: Astronomers crack mystery of the "monster stars" - Astronomy Magazine

It is also theorized that stars above 250 solar masses do not die in a pair-instability supernova, or hypernova, like stars in the 130 to 250 solar mass range. Stars with masses greater than 250 solar masses do form black holes, or so it has been suggested. I have not yet seen the physics as to why they are suggesting this theory.

The above article also suggests that the largest star that can form through the gravitational collapse of gas and dust is still at around 150 solar masses, and that stars with more than 150 solar masses could only have been created through the collision of other stars.