Neutron Stars.. Is there anything in the universe that can hold two neutrons stars up?

[M06Abe]

Hey, first of all, am new here and I have loved Astronomy and learning about the cosmos since I was about 5, but I have huge gaps in my knowledge.. so I am starting off as a noob in astronomy, so go easy on me lol !

Anyway, I was wondering if there is any object or anything that exist in the observable universe that can hold up two neutron stars? Just a general question that's plagued my mind for sometime

[gkec]

Hey, first of all, am new here and I have loved Astronomy and learning about the cosmos since I was about 5, but I have huge gaps in my knowledge.. so I am starting off as a noob in astronomy, so go easy on me lol !

Anyway, I was wondering if there is any object or anything that exist in the observable universe that can hold up two neutron stars? Just a general question that's plagued my mind for sometime

What do you mean by "hold up"? I do realise it is not stand and deliver "hold up"!

[VigdisVZ]

First of all hi and welcome. Also define "hold up".

[M06Abe]

Hey, sorry I was vague by saying hold up. Well I watched a documentary earlier today and the narrator was talking about neutrons stars and literally said my question. hesaid "hold up". I guess maybe he meant, can anything stop them from collapsing under their combined gravity ?

He said something about a table spoon of of the mass of a neutron star may way about the same as a Musashi battleship on earth. (I can see exaggeration.. Maybe). Not sure if am making sense to you guys, i'll stop here.

[VigdisVZ]

Well, I think neutron stars are in a semi collapsted state. Like dense enough to be like they are, but lacking mass to make reality collapse on itself and create a black hole. I'm guessing they would be pretty stable since they still lack a lot of mass to collapse further. You could probably find out a lot more by checking out the wikipedia article etc. but since they pretty much need quantum physics to make heads or tails of, be prepared for a ride.

Also be a bit skeptic about modern documentaries always trying to "teach" adults by using silly comparisons. Those always get under my skin

[M06Abe]

Well, I think neutron stars are in a semi collapsted state. Like dense enough to be like they are, but lacking mass to make reality collapse on itself and create a black hole. I'm guessing they would be pretty stable since they still lack a lot of mass to collapse further. You could probably find out a lot more by checking out the wikipedia article etc. but since they pretty much need quantum physics to make heads or tails of, be prepared for a ride.

Also be a bit skeptic about modern documentaries always trying to "teach" adults by using silly comparisons. Those always get under my skin

Ahh fair enough. That's good enough for me haha. Yeah I understand the semi collapsed state, just not enough mass to go black hole status. May have to do some wiki research. And yeah the comparison wasn't the finest one he could of used ¬¬ . Thanks !

[JulianO]

There are about 3 or 4 states the remnants of stars can end up in, determined by how much mass is left after the stars death throws.

A white dwarf is "held up" from collapsing further by electron degeneracy pressure. White dwarfs are very compact objects, with the mass of the sun forming an object about the size of the Earth. The structure is squeezed into the smallest space where atoms can still exist, but filling up all the quantum states allowed for the electrons, which exerts a pressure sufficient to stop further collapse. White dwarfs are typically up to about 1.5 solar masses. The density is high, having squashed the mass of the sun into the earth, so about one ton per cm³. Oddly enough, if you add more matter to a white dwarf, it gets smaller!

Next are neutron stars, which form above the Chandrasekhar limit where the electrons are further squashed so they combine with protons into neutrons. Hence the name neutron star. These are above around 1.5 solar masses, but now squashed into something the size of a big city, about 10km across. Therefore the density is huge. Its about 100,000,000 tons per cm³. The battleship is about right. Other scales are a 747 squashed into a grain of sand, or a teaspoon of material would be 900 times the mass of the large pyramid at Giza.

Squash it further - somewhere greater than ~3 to 5 solar masses and you get a black hole, where there is nothing left to resist the gravitational collapse and it all falls in on itself.

There is a possibility of a quark star somewhere between these two where material is so compressed only quarks can exist upholding gravity - but its still not clear if that might happen.

[moogoomonkey]

There is a possibility of a quark star somewhere between these two where material is so compressed only quarks can exist upholding gravity - but its still not clear if that might happen.

I though quarks couldn't exist alone, they need to be in a triplet?

[DirkSteele]

Quarks exist as colour neutral, but that can also be a paring of quark and anti quark as seen in Mesons as well as triplets seen in baryonic matter that you refer to. Other theoretical frameworks have been proposed such as a pentaquark (4 quarks plus one anti quark). Jury is still out on that one and even more exotic arrangements.

[JulianO]

I though quarks couldn't exist alone, they need to be in a triplet?

As I understand it, the individual nuclei break down into quarks, which assemble into some sort of giant nucleus held together by gravity.

[symesie04]

Also worth noting that there are indeed several classes of Neutron stars. As well as the quark stars the exotic class also has several other candidates (hyperthetical of course). But Neutron stars also include Pulsars both single and Binary each of what have their own sub classes. Also there is the fascinating Magnetar with its own 2 sub classes. I think that Neutron stars really must be regarded as among the most intriguing objects in the Universe.

[Phil Fargaze]

Anyway, I was wondering if there is any object or anything that exist in the observable universe that can hold up two neutron stars?

I was thinking about what you say about two neutron stars. I think I remember reading about a recent discovery that there can be a circumstance when two neutron stars are in close orbit which eventually decays to a unification. The resulting mass of the two objects results in a formation of a black hole. Maybe that is what the documentary was getting at.

[ollypenrice]

Yes, I'd assume that the issue is whether or not two neutron stars, once merged, could resist collapse and I'd have thought not. Julian?

Neutron stars are indeed intriguing, though the man who proposed them runs them close. Fritz Zwicky. One of his colleagues said that the Zwicky should be a unit of abrasiveness and another said that no known abrasavie could possibly even qualify for one Microzwicky...

Olly

[JamesF]

Could be quite spectacular seeing two neutron stars combine (from a safe distance

All that angular momentum...

James

[Phil Fargaze]

There are a few articles about neutron star mergers. I came up with this one after a quick search.

http://www.astronomynow.com/news/n1109/14gold/

Looks like it`s a method to create heavy elements but no mention of black holes.

[george7378]

The likelihood is that if two neutron stars collide, the degeneracy pressure supporting them will not be strong enough to overcome their gravitational collapse and they will explode as a type 1a supernova.

[JulianO]

I'm not sure what happens when two neutrons stars merge, but I know it is one of the key events that gravitational wave telescopes look for. They should lose a lot of energy by emitting gravitational waves, and so are strong enough to be detected - well hopefully. So far the existing detectors have yet to detect anything, although it has to be said the task is staggeringly hard to pull off!

Type 1a's involve stealing hydrogen and helium from other stars whilst being in a electron degenerate state - a white dwarf. Neutron stars are already past the electron degeneracy limit, so whether I suspect a type 1a is probably not going to happen. This article seems to indicate it just ends up as a bigger neutron star. http://iopscience.iop.org/2041-8205/734/2/L36 - but if exceeds the limit, it will become a black hole.

[Ptarmigan]

a paring of quark and anti quark as seen in Mesons

What stops them annihilating, like an electron-positron pair, to high energy photons as soon as they come close,

how do they get bound in a meson first and sometimes decay to other particles?

[DirkSteele]

What stops them annihilating, like an electron-positron pair, to high energy photons as soon as they come close,

how do they get bound in a meson first and sometimes decay to other particles?

Nothing does. Mesons are very short lived particles (the longest of which has a lifetime of only a few hundreds of a microsecond) bound together by the strong nuclear force. Charged versions decay in to electrons and neutrinos and uncharged versions may decay into Photons. They are the products of high energy interactions between matter made of quarks. They are often seen as the product of cosmic rays interacting with particles in the upper atmosphere (which was one of my favourite experiments in the 3rd year of my physics degree).

[spurius]

What is a quark?

Anyway black holes gravity is so strong that not even light can escape. This is why they consume everything around them, making them more massive which makes them even more powerful. Eventualy black holes will consume everything in the universe including each other. So the fate of the universe will leave it being one super massive black hole with sod all else in it.

[JulianO]

What is a quark?

Quarks are the fundamental building blocks of hadrons. We use to think atoms were the smallest individual things, but then found out they were made of electrons, protons and neutrons. Now we find that protons and neutrons are made of 3 quarks. There are six types of quark, which come in sort of pairs, with fractional charges.

up (u +2/3) and down (d -1/3) - pretty much everything normal is made of these

charm (c +2/3) and strange (s -1/3)

top (t +2/3) and bottom (b -1/3) (or truth and beauty)

A proton is made of uud (two ups and a down) - if you add up the charges it comes out as +1

A neutron is made of udd - likewise comes out as 0 charge.

For each quark there is an opposite and equal anti-quark. Usually written with a bar over it.

A meson is a quark/anti-quark pair, and they are all unstable, lasting for fractions of seconds down to fractions of fractions of seconds!

There are a whole load of them you can make in reactions, having different combinations of quark/anti-quarks.

Anyway black holes gravity is so strong that not even light can escape. This is why they consume everything around them, making them more massive which makes them even more powerful. Eventualy black holes will consume everything in the universe including each other. So the fate of the universe will leave it being one super massive black hole with sod all else in it.

They won't consume everything, they'll just consume anything that gets in their way! It's quite possible to have a planet in a stable orbit around one, or a sun.

[DirkSteele]

A Quark is an elementary particle and fundamental building block of matter. Quarks combine to form most of the matter that you and I would be familiar with, called Hadrons such as protons and neutrons. Quarks have a property known as colour, and because of a mechanism known as colour confinement, quarks are never observed in singular form. The colours being Red, Blue and Green. All three colours must be present in a Hadron (effectively you can think of the three colours equalling white), or a colour and anti-colour in the case of a Meson (which I mentioned in a post above) which still leaves the particle colour neutral. They are also interesting because they are the only fundamental particle which interacts by all 4 fundamental forces, Strong, Weak, Electromagnetism and Gravity. They are also the only particles whose electric charge is not a whole integer multiple of the elementary charge.

They also come in 6 “flavours” – Up, Down, Top, Bottom, Strange, and Charm.

[DirkSteele]

Whoops, should type faster!