A neutron star is the final stage of the graviational collapse of a massive supergiant star. Except for black holes, neutron stars are the smallest and densest currently known class of stellar objects
Questions tagged [neutron-stars]
399 questions
72
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How come neutrons in a nucleus don't decay?
I know outside a nucleus, neutrons are unstable and they have half life of about 15 minutes. But when they are together with protons inside the nucleus, they are stable. How does that happen?
I got this from wikipedia:
When bound inside of a…
Aria
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Do all black holes have a singularity?
If a large star goes supernova, but not enough mass collapses to form a black hole, it often forms a neutron star. My understanding is that this is the densest object that can exist because of the Pauli exclusion principle: It's made entirely of…
Carson Myers
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Why did the gamma ray burst from GW170817 lag two seconds behind the gravitational wave?
The ABC, reporting on the announcement of gravitational wave GW170817, explained that for the first time we could identify the precise source of a gravitational wave because we also observed the event in the electromagnetic spectrum. It notes…
curiousdannii
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Why are planets not crushed by gravity?
Stars can be crushed by gravity and create black holes or neutron stars. Why doesn't the same happen with any planet if it is in the same space time?
Please explain it in simple way. Note: I am not a physicist but have some interest in physics.
NotPhysicist
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38
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4 answers
What stabilizes neutrons against beta decay in a neutron star?
Free neutrons are known to undergo beta decay with a half-life of slightly above 10 minutes. Binding with other nucleons stabilizes the neutrons in an atomic nucleus, but only if the fraction of protons is high enough (at least a third or so). But…
Slaviks
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What is the theoretical lower mass limit for a gravitationally stable neutron star?
I ask here intentionally not for the size of the smallest possible observed size of neutron stars, which corresponds approximately to the well-known Chandrasekhar-limit for the upper limit of the white dwarfs. This is defined by the minimal size of…
peterh
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How do LIGO and Virgo know that a gravitational wave has its origin in a neutron star or a black hole?
It is being said that gravitational-wave detectors are now able to distinguish neutron star waves from those originating from black holes.
Two Questions:
How do LIGO and Virgo know that a gravitational wave has its origin in a neutron star or a…
João Bosco
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2 answers
Can a neutron star become a black hole via cooling?
How much does thermal expansion affect neutron stars? Would the loss of temperature cause a neutron star to be more densely packed and thus collapse into a black hole?
user289661
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5 answers
Can there be Electron and/or Proton Stars?
What happens to all of the electrons and protons in the material of a neutron star?
Could there ever be an electron star or a proton star?
Shookster
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What would happen to a teaspoon of neutron star material if released on Earth?
I've read on NASA's page on neutron star that one teaspoonful of that star would weigh over 20 billion tonnes on Earth. If it was somehow possible to bring it to earth would it:
Burn and disappear during Earth atmosphere entry?
Assuming we have 20…
Blue Pony Inc.
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Why did the neutron star merger signal last for so much longer than the black hole merger signals?
Just recently, LIGO and Virgo successfully detected new signs of gravitational waves. This time, instead of colliding black holes, it is a pair of colliding neutron stars. This collision emits light and gravitational waves.
I read in CNN: First-seen…
29
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Why do neutrons repel each other?
I can understand why 2 protons will repel each other, because they're both positive. But there isn't a neutral charge is there? So why do neutrons repel? (Do they, or have I been misinformed?)
The reason why I'm asking this is because, I've just…
Jonathan.
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Are Neutron stars transparent?
Neutrons have no charge so they would not, I think, interact with photons. Would a neutron star be transparent?
Joe Zorskie
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What happens to Protons and Electrons when a Neutron star forms?
What happens to Protons and Electrons when a Neutron star forms? At some point gravity overcomes the Pauli Exclusion Principle ( I assume) and they are all forced together. What happens in the process?
user56903
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4 answers
Due to relativity, does the surface of a pulsar have less area than the layer beneath it?
A pulsar or spinning neutron star can reach relativistic angular velocities. Special relativity asserts that objects traveling near the speed of light contract in length. Therefore, it seems reasonable that a rapidly rotating object could exhibit a…
Master Drifter
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