Questions tagged [neutron-star]
Questions regarding a degenerate star that is mainly composed of neutrons.
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Do neutron stars have an ergosphere?
Ergospheres are a property of black holes, and do neutron stars have it? If yes, why seldom article mentions that; if no, why can't neutron stars have this ergosphere component?
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How could we search for old cold neutron stars?
This is the inverse of Will Gaia detect inactive neutron stars? (to which the answer was "probably not").
So if Gaia can't do it, what would it take? How could such a search work, and what ...
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Assuming proton decay is false, what's the ultimate fate of a neutron star or white dwarf?
A still unproven theory that protons can decay, and have a halflife of $10^{30}$ years or so, meaning eventually all matter will dissolve because their constituent protons and therefore neutrons will ...
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Is nuclear pasta or neutron star crust iron stable outside of neutron stars?
When neutron stars collide, they crash into and kill each other in a kilonova explosion, which blasts a lot of their material into space. A huge amount of neutronium, neutron star stuff, is suddenly ...
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Is there a Vela Nebula?
The Vela pulsar is a neutron star from a supernova that exploded 10,000 years ago. It spins 11 times a second. The Crab Nebula along with the central Crab Pulsar formed 1000 years ago. This pulsar ...
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How did Fermi manage to see neutron star merger?
When the GW170817 neutron stars merger was observed by LIGO/Virgo, the Fermi gamma-ray telescope observed the event 2s after the merge. How did it know where and when to look? It must take some time ...
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Why do objects appear blue while on a neutron star?
I was playing around in Space Engine recently, and I realized I hadn't yet landed on a neutron star. This seemed like a very sensible thing to do, so I did it and chose a (relatively) well-known one ...
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Can a pulsar also be a magnetar?
I know this is a simplistic question, but I cannot find a straight answer...
Also, is it possible most or all neutron stars are magnetars and/or pulsars? It's just hard to see all of their properties ...
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How likely are planets to form after neutron star collisions?
It is well known that planetary collisions can create moons orbiting the result of the merger if they happen in the correct way, and this is how the Earth's moon is believed to have been formed. See ...
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What methodology should be used to choose the correct model for origin of QPOs in X-ray astronomy?
In X-ray astronomy, quasi periodic oscillations (QPOs) are routinely shown by black hole and neutron star X-ray binary systems in their X-ray flux. Despite being strong and easily measurable signals, ...
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What would happen on earth if there was a surge in gravitational waves [duplicate]
There are claims that when massive objects merge some of their mass is converted to gravitational energy. Such as the following links:
https://astronomy.stackexchange.com/a/38727/2305
https://youtu.be/...
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Fraction of initial mass lost (radiated) by neutron star mergers compared to black hole mergers?
GW190521 black hole merger total mass calculation and missing mass, how does this happen? notes that there are about 9 solar masses missing from the final black hole.
GW170817 is the first observed ...
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If a pulsar's rotational and magnetic axes were aligned and both aimed at us, would we see a steady radio source?
In other words, a non-pulsing pulsar?
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Do the neutrons in neutron stars emit the radio waves?
Neutrons can, especially in extreme circumstances (and large concentrations) emit electromagnetic radiation. I specifically asked about this in Physics S.E. Has a free neutron ever been shown to ...
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How is angular momentum transferred between a neutron star and its accretion disk?
Accreting neutron stars can either gain or loose angular momentum via interaction with their accretion disks. This leads to either spin-up or spin-down. Which of the two is the case, depends on the ...
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If the sun is a second or third generation star, where is the neutron star? [duplicate]
It is widely believed that before the Sun was another star, more pristine in its composition (mostly Hydrogen and perhaps some Helium). And maybe before it was yet another. This blog explains this via ...
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Is there any synthetic spectrum software for neutron star?
Is there any software that can calculate the emergent spectrum of a neutron star photosphere, for Teff is about 1e7K, density is above 1e21-1e22 cm^-3 ? Output line wavelength is about 0-100A is ...
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Why can there be several seconds of lag between a binary neutron star merger and the emission of gamma rays from the same area?
Answers to: Gravitational waves and gamma ray burst: how were the error bars determined for this speed of gravity calculation? Was $H_0$ used? go into substantial detail explaining this determination. ...
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What is the “hypothesized lower mass gap” between 2.5 and 5 solar masses?
Searching here for "mass gap" yields nothing yet. Penn State's Black hole or neutron star? LIGO-Virgo scientists find mystery object in 'mass gap' begins:
When the most massive stars die, ...
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Can the Sun contain degenerate matter?
Degenerate matter (neutronium) is hypothesized to be very dense and, at a certain amount, unstable - in the sense of collapsing on itself and causing fusion. The result would be a massive fusion ...
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Are there neutron stars whose magnetic axis and rotating axis are the same, and if so what will happen?
I know that there's probably a higher chance of having a neutron star that has its magnetic axis inclined to the rotational axis rather than having it perfectly aligned.
If they are not aligned, the ...
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Is the object a pulsar
We have a star having 1.8 solar mass. Justify any four means (measurable/ observed properties) by which you can identify that the object is a Pulsar and not a white dwarf or a Black Hole.
So one ...
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In practice, can very high magnetic fields significantly alter the dynamics of an astronomical-scale bodies?
The direct effect of magnetic fields on the dynamics (as in the movements, trajectories etc of the bodies themselves, rather than lower-level phenomena like stellar winds and atmospheric degradation) ...
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How far away are the events that caused the gravitational waves that have been detected?
A certain number of gravitational wave events have been detected. Is it possible to know how far away the mergers that caused those gravitational wave events are?
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Is the atmosphere of neutron star solid, liquid or gaseous state? [duplicate]
Neutron star has a thin layer of atmosphere consist mostly of hydrogen and helium and is about less than a metre thick on average, but what wasn't stated in many articles I read is the state of matter ...
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How does the field decay of a magnetar power the emission of high-energy electromagnetic radiation?
In Space.com's Dr. Pulsar and Mr. Magnetar? 2 Star Types May Turn into Each Other (and in the linked video) "Tom Prince, a physics professor at the California Institute of Technology and a senior ...
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Can we detect pulsars that aren't “pointed” towards us?
A pulsar is a highly magnetized rotating neutron star that emits beams of radiation through its magnetic poles, in the direction of the Earth. This makes it seem to pulse, as seen from Earth. There ...
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How can I hear (or at least detect) a pulsar at home?
Scott Manley's video Using Relativistic Raytracing &X-Rays To See Detail on Surface Of Neutron Star talks about X-ray measurements using the NICER X-ray telescope attached to the International ...
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If we accelerate a neutron star to move at speeds comparable to light would it become a blackhole because of the added energy?
Could a neutron star turn into a blackhole if it is accelerated to near luminal velocities? And if it slows down after a while, does it become a neutron star again?
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What is the “radiation sound speed” inside an accretion column?
I was trying to read "A New Two-fluid Radiation-hydrodynamical Model for X-Ray Pulsar Accretion Columns" and its follow-up paper both by West et al. and came across a quantity called "radiation sound ...
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Neutron star size in different reference frames
What is the estimated size of neutron stars observed in their reference frame and in our reference frame?
That is, how bent is space-time around neutron stars?
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Could anything consume a small black hole?
Whenever I read about black holes, it is normally involving how they devour anything that comes too close... regardless of how big anything is.
But what if it were a really small black hole vs ...
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Neutron star r-process nucleosynthesis
The $r$-process in supernovae happens when a high flux of neutrons irradiates the heaviest abundant nuclei (in the region of iron), resulting in endothermic nuclear reactions.
To the extent that at ...
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Radiation from Neutron Star impact?
As I understand it, objects falling into an old/inactive/dead/non-pulsar neutron star would be ripped apart, form an accretion disc and eventually emit a burst of radiation as they fall onto the ...
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Is there evidence of super-heavy elements in the x-ray and gamma-ray spectrums of neutron stars?
It occurs to me, that between the surface and interior of neutron stars, gravitational pressure might produce super-heavy elements and that signatures of such elements might be detectable in the star'...
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A neutron star without a flat surface and an atmosphere?
In the Kurzgesagt video Atoms As Big As Mountains — Neutron Stars Explained they state that neutron stars have an atmosphere that reaches about 10 centimeters above the surface.
How is this possible?...
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Binary pairings that haven't been discovered yet?
Question: Are there any kinds of binary pairings that haven't been discovered yet? Any that are particularly significant, or that might shed some light on binary stellar evolution or theories of ...
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Roche Zone of a black hole vs Roche Zone of Neutron Star
Suppose a very unusually small back hole with the mass of about, lets say, 1.5 solar masses(hawking radiation should destroy a lot of mass let's assume). It thus would have a Roche limit smaller than ...
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What does “GPU-accelerated butterfly matched filtering over dense bank of time-symmetric chirp-like templates” mean? (GW170817)
A new analysis of gravitational wave (and other data) from GW170817 on 2017-Aug-17 has been published, strongly suggesting that the merger of two neutron stars resulted in a large, rapidly rotating ...
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A high-temperature isolated neutron star could be super-Eddington?
If the surface temperature of a young neutron star is hot enough, say, several KeV, its blackbody radiation could be super-Eddington?
Did any paper discuss this scenario before?
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Could an astronomical process create elements in the islands of stability?
I was reading about heavy elements recently, and I took note of the theorized islands of stability, and how some the elements involved are considerably heavier than anything we've been able to ...
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What is Propeller Effect exactly?
I find the original reference seems to be here. I still do not understand the mechanism. It is necessarily occur in neutron binaries? Anyone can introduce it in detail? This paper is old.
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How big should be a piece of neutron star to reach Earth's mass?
Imagine a neutron star could be broke into pieces.
How big would be the piece matching Earth's mass?
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Why aren't neutron stars full of dark matter?
Dark matter interacts with the gravitational force right? Well, unlike black holes, neutron stars are actually visible, and they're an enormous gravitational sink, so dark matter should collect to ...
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Why do neutron stars collide instead of just revolving around each other like planets revolve around the Sun?
We know about events like two neutron star colliding and resulting in a black hole, also collision of black holes, and collision of galaxies. But we never see a satellite such as a moon colliding with ...
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Is there a possibility that a white dwarf can turn into a neutron star or a black hole?
I know that a white dwarf is mainly balanced by electron degeneracy pressure and that if it gains more than 1.4 solar masses from any source (such as a companion star or a collision), it explodes as a ...
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Core collapse supernova vs Neutron Star
I am reading about massive stars and their final consequences. what I understood is massive stars after throwing out their outer envelop with masses > 1.4 solar Mass turn into neutron stars. But I ...
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What is the light that we see from a neutron star come from?
What hold the electrons in orbit? Is it gravity or the atomic attraction between the protons and neutrons?
I asked this question on Physics SE I hope I improved on the quality enough to do better ...
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Can we create neutron star by pressing earth? Or other objects?
Everywhere I can hear, that if we press anything to the right size, we create black hole.
Can we create neutron star by pressing, for example, our planet? And what if we press something bigger, like ...
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How do we know how fast the surface of a neutron star is rotating?
I understand that we can count pulses in time, but how do we know that the magnetosphere is rotating along with the surface of a neutron star?
Can we measure the rotation of a neutron star in any ...
