Hello. New scifag here. I just watched a video and there was a star that was as large as 764150203826 earths. How can something be this massive and not just... collapse? Im not too sure what the word would be but... How can this be possible? Just curious.

Im not educated enough in astronomy to provide a proper answer but you should like this image.

Seriously now... look at that cantus star. that is some major bullshit. that star is just too big to be stable enough not to just explode, collapse, w.e stars do.
Edit: as for the pictures of the galaxies / stars from hubble, i believe that. that makes sense and can easily be real. But the cantis star is just too large.

This post was edited by LoLBrouMad on Jan 22 2011 06:19pm

no other way is better to make you think of how insignificant you are than that picture

The thing is, gravity's actually an incredibly weak force by comparison to every other fundamental force (this is why you can have dust clinging to the ceiling -- a small amount of electric force is more than enough to "overcome" gravity and prevent the dust from falling). There is so much energy being released inside the star due to nuclear fusion that there just isn't any way for the star to collapse.

Even then, not all stars do collapse. Stars the size of our Sun actually greatly expand during the period of their death (the Sun will inflate to the size of about Mars' orbit once it starts fusing Helium into Carbon (2He Be, Be + He C) because there will be a lot more energy and gravity won't be enough to contain it until that cycle's done), though after that expansion they do shrink back down eventually (after there's nothing left to undergo fusion, the energy output drops dramatically so gravity can overcome the star's size) and it will become a brown dwarf.

Stars that are much larger than our Sun get hot enough in their core to burn past Carbon. In fact, the most massive stars in the universe are able to undergo fusion until the primary thing left in the star is Iron (there can be no fusion past iron because the bonding energy per nucleon is greatest in iron; this is how we know that all elements with nuclei heavier than Iron's were created during supernovae). Though the process isn't fully understood (it's also possible that it is understood now and I just haven't read about it), these super-massive stars DO collapse after they're done burning into Iron. The thing is, though, with these super-massive stars, as a result of their rapid collapse they start emitting Neutrinos, and once the star isn't able to collapse any further, the star's remaining material rebounds and explodes outward again. This is what we know as a supernova.

Depending on the amount of mass left behind after the supernova, any number of things can happen. This is where we get neutron stars and black holes. I'm remembering the terms "electron degeneracy" and "neutron degeneracy" right now, but I can't remember where it fits into it all, to be honest. Something worth looking up for yourself if you're interested.

This post was edited by bentherdonethat on Jan 23 2011 01:37am

it doesnt matter how big the stars are. as they burn the hydrogen in their core, particles push their way to the surface of the star before being ejected out into space, this internal pressure offsets gravitational collapse keeping the star uniform and together. when it finally burns out all its fuel then it will go supernova and probably collapse, creating a black hole, end of story.

This post was edited by sirfrozt on Jan 23 2011 01:32am

Actually the expansion into a Red Giant is not because the star can't contain its energy. I forget word for word but it expands because it is forcing its internal temperature higher to facilitate fusion of He.

Electron Degeneracy means that the atoms are smashed together so tightly that electrons are virtually touching. Much like electron Neutron degeneracy is the same thing only on the neutron level. At least thats how it was explained to me.

and i would imagine thats bad somehow?

either way it would be some dense ass stuff

From Wiki

A neutron star is so dense that one teaspoon (5 milliliters) of its material would have a mass over 5.5×10^12
kg, about 900 times the mass of the Great Pyramid of Giza.

Can't find the same information for a white dwarf, but as for densities go:

Material Density in kg/m3 Notes
Water (fresh) 1000 At STP
Osmium 22610 Near room temperature
The core of the Sun ~150000
White dwarf star 1 × 10^9[1]
Atomic nuclei 2.3 × 10^17 [31] Does not depend strongly on size of nucleus
Neutron star 8.4 × 10^16 − 1 × 10^18
Black hole 2 × 10^30 [citation needed] Mean density inside the Schwarzschild radius of an Earth-mass black hole (theoretical)

This post was edited by Aisu_aS on Jan 23 2011 01:54am

because gravity is weak and the amount of energy out outward force the star is producing is slightly greater then gravity but once it runs out of fuel and the outward force decreases gravity will win and it will explode into a super nova resulting in a black hole or a neutron star