Is the Chandrasakar limit under threat here?

[R1Geezer]

http://www.bbc.co.uk/...-environment-11011118
The measurments seem accurate, so why did this not become a black hole? One theory seems to be that there may be a black hole binary partner close by that sucked in some of the matter but surely that would have caused a serious wobble in the magnetars position. Your theories are welcome!

[jake-the-peg]

Possible Quark star contender

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

[jomifl]

pass

[New Judge]

As far as my amateur, layman’s astro-physics goes I was under the impression that Chandrasekhar’s limit (which I believe is about 1.4 solar masses) was the limit of stellar mass above which a dying star was bound to collapse to form either a Black Hole or a Neutron Star. (What determines the fate of the star, from those two options, I do not know). Below that mass, the star would collapse to the “White Dwarf” and eventually the “Black Dwarf” state.

Looking at Jake’s link it seems that scientists have developed a model which describes further alternatives for the fate of massive stars, but these seem nonetheless to be variations on the Neutron Star/Black Hole theory of evolution (something I have not kept up with). Reading the Wiki article very quickly (I’ve got to go out for a beer this lunchtime and have limited time) it would seem that Chandrasekhar’s limit is not under threat as the mass of the newly discovered star is above the threshold for collapse into a White Dwarf. Since it has not collapsed into that state but is simply exhibiting differences to the accepted Neutron Star/Black Hole theory I don’t think the late Chandra’s relatives need consider handing back his Nobel Prize just yet.

Unless you think differently, Jake!

[R1Geezer]

There is a higher limit of around 7 solar masses that mean it would collapse to a blackhole, ie beyond a neutron star. This is 40+ solar masses.

[New Judge]

At the bottom of this document, Geezer:

http://www.ph.surrey...._stars_end.html#white

is s summaty of the fate of dying stars in trlation to their mass. It suggests tthat Black Holes are formed from stars of >10 Solar Masses.

[New Judge]

Should be:

...a summary of the fate of dying stars in relation...

[R1Geezer]

Ok judge, 10,so why didn't the 40 solar mass star become a black hole, that's the conundrum

[New Judge]

Dunno.

Perhaps Jake can help.

[New Judge]

But thinking about it, did Chandra say “less than 1.4 SM’s, collapse will be to White Dwarf (stable), >1.4, collapse will be to something more bizarre (Neutron Star, Black Hole or something else)? Or did he say, “...>1.4 must collapse [only] to Neutron Star or Black Hole”?

If the former, then perhaps his theory is still valid. This star did not remain as a White Dwarf, but something more bizarre.

Just thinking out loud.