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Encyclopedia > Neutron star

A neutron star is formed from the collapsed remnant of a massive star, a Type II, Type Ib, or Type Ic supernova and models predict that it consists mostly of neutrons. It is a very hot star supported by the Pauli exclusion principle repulsion between neutrons. A neutron star is one of the few possible conclusions of stellar evolution. Larry Nivens short story Neutron Star, published in 1966, is widely considered to be the literary cornerstone of his Known Space collection. ... This article or section does not adequately cite its references or sources. ... This article or section does not cite its references or sources. ... For other uses, see Supernova (disambiguation). ... For other uses, see Supernova (disambiguation). ... For other uses, see Supernova (disambiguation). ... For other uses, see Supernova (disambiguation). ... The Pauli exclusion principle is a quantum mechanical principle formulated by Wolfgang Pauli in 1925. ... In astronomy, the term compact star (sometimes compact object) is used to refer collectively to white dwarfs, neutron stars, other exotic dense stars, and black holes. ... Projected timeline of the Suns life In astronomy, stellar evolution is the process by which a star undergoes a sequence of radical changes during its lifetime. ...


A typical neutron star has a mass between 1.35 and about 2.1 solar masses, with a corresponding radius between 20 and 10 km — 30,000 to 70,000 times smaller than the Sun. Thus, neutron stars have overall densities of 8.4×1016 to 1×1018 kg/,[1] which compares with the approximate density of an atomic nucleus of 3×1017 kg/m³.[2] The neutron star's density varies from below 1×109 kg/m³ in the crust increasing with depth to above 6 or 8×1017 kg/m³ deeper inside.[3] For other uses, see Mass (disambiguation). ... To help compare different orders of magnitude, the following list describes various mass levels between 10−36 kg and 1053 kg. ... In astronomy, the solar mass is a unit of mass used to express the mass of stars and larger objects such as galaxies. ... This article is about an authentication, authorization, and accounting protocol. ... “km” redirects here. ... Sol redirects here. ... Conversion Calculator for Units of Density PICKLES Category: ... Kg redirects here. ... The cubic meter (symbol m³) is the SI derived unit of volume. ... The nucleus of an atom is the very small dense region, of positive charge, in its centre consisting of nucleons (protons and neutrons). ... Conversion Calculator for Units of Density PICKLES Category: ... Conversion Calculator for Units of Density PICKLES Category: ... Conversion Calculator for Units of Density PICKLES Category: ...


In general, compact stars of less than 1.38 solar masses, the Chandrasekhar limit, are white dwarfs; above 2 to 3 solar masses (the Tolman-Oppenheimer-Volkoff limit), a Quark star might be created, however this is uncertain. Gravitational collapse will always occur on any star over 5 solar masses, inevitably producing a black hole. The Chandrasekhar limit, is the maximum mass possible for a white dwarf (one of the end stages of stars when they cool down) and is approximately 3 × 1030 kg, around 1. ... This article or section does not adequately cite its references or sources. ... This article is in need of attention from an expert on the subject. ... A strange star or quark star is a hypothetical type of star composed of strange matter, or quark matter. ... This article or section does not cite its references or sources. ... For other uses, see Black hole (disambiguation). ...

Contents

Formation

As the core of a massive star is compressed during a supernova, and collapses into a neutron star, it retains most of its angular momentum. Since it has only a tiny fraction of its parent's radius (and therefore its moment of inertia is sharply reduced), a neutron star is formed with very high rotation speed, and then gradually slows down. Neutron stars are known to have rotation periods between about 1.4ms to thirty seconds. The neutron star's compactness also gives it very high surface gravity, 2×1011 to 3×1012 times stronger than that of Earth. One measure of such immense gravity is the fact that neutron stars have an escape velocity of around 150,000 km/s, about 50psl. Matter falling onto the surface of a neutron star would be super-accelerated by this gravity and the force of impact would likely destroy the object's component atoms, rendering all its matter identical, in most respects, to the rest of the star. For other uses, see Supernova (disambiguation). ... This gyroscope remains upright while spinning due to its angular momentum. ... Moment of inertia, also called mass moment of inertia and, sometimes, the angular mass, (SI units kg m², Former British units slug ft2), is the rotational analog of mass. ... The surface gravity of a Killing horizon is the acceleration, as exerted at infinity, needed to keep an object at the horizon. ... This article is about Earth as a planet. ... Space Shuttle Atlantis launches on mission STS-71. ... To help compare different orders of magnitude, the following list describes various speed levels between 1. ... PSL PSL is a short hand form of saying Percentage Light Speed, or more correctly Percentage of the speed of light. ...


Structure

A model of a neutron star's internal structure
A model of a neutron star's internal structure

Current understanding of the structure of neutron stars is defined by existing mathematical models. A neutron star is so dense that one teaspoon (5 millilitre) of its material would mass over 5000 million metric tons (5×1012 kg).[4] On the basis of current models, the matter at the surface of a neutron star is composed of ordinary atomic nuclei as well as electrons. The "atmosphere" of the star is roughly one meter thick, below which one encounters a solid "crust". Proceeding inward, one encounters nuclei with ever increasing numbers of neutrons; such nuclei would quickly decay on Earth, but are kept stable by tremendous pressures. Proceeding deeper, one comes to a point called neutron drip where free neutrons leak out of nuclei. In this region, there are nuclei, free electrons, and free neutrons. The nuclei become smaller and smaller until the core is reached, by definition the point where they disappear altogether. The exact nature of the superdense matter in the core is still not well understood. While this theoretical substance is referred to as neutronium in science fiction and popular literature, the term "neutronium" is rarely used in scientific publications, due to ambiguity over its meaning. The term neutron-degenerate matter is sometimes used, though not universally as the term incorporates assumptions about the nature of neutron star core material. Neutron star core material could be a superfluid mixture of neutrons with a few protons and electrons, or it could incorporate high-energy particles like pions and kaons in addition to neutrons, or it could be composed of strange matter incorporating quarks heavier than up and down quarks, or it could be quark matter not bound into hadrons. (A compact star composed entirely of strange matter would be called a strange star.) However so far observations have neither indicated nor ruled out such exotic states of matter. Image File history File links Download high resolution version (1280x1024, 210 KB) Retrieved July 18, 2005 from [1] From page: File links The following pages link to this file: Neutron star ... Image File history File links Download high resolution version (1280x1024, 210 KB) Retrieved July 18, 2005 from [1] From page: File links The following pages link to this file: Neutron star ... The pages linked in the right-hand column contain lists of volumes that are of the same order of magnitude (power of ten). ... The millilitre is the equivalent of a cubic centimetre. ... To help compare different orders of magnitude, the following list describes various mass levels between 10−36 kg and 1053 kg. ... The nucleus of an atom is the very small dense region, of positive charge, in its centre consisting of nucleons (protons and neutrons). ... For other uses, see Electron (disambiguation). ... Neutron drip line is a concept in particle and nuclear physics. ... Neutronium is a term used in science fiction and popular literature to refer to an extremely dense phase of matter composed primarily of neutrons. ... Science fiction is a form of speculative fiction principally dealing with the impact of imagined science and technology, or both, upon society and persons as individuals. ... Degenerate matter is matter which has sufficiently high density that the dominant contribution to its pressure arises from the Pauli exclusion principle. ... Helium II will creep along surfaces in order to find its own level - after a short while, the levels in the two containers will equalize. ... For other uses, see Proton (disambiguation). ... In particle physics, pion (short for pi meson) is the collective name for three subatomic particles: Ï€0, Ï€+ and π−. Pions are the lightest mesons and play an important role in explaining low-energy properties of the strong nuclear force. ... In particle physics, Kaons (also called K-mesons and denoted K) are a group of four mesons distinguished by the fact that they carry a quantum number called strangeness. ... This article is considered orphaned, since there are very few or no other articles that link to this one. ... For other uses, see Quark (disambiguation). ... The up quark is a first-generation quark with a charge of +(2/3)e. ... The down quark is a first-generation quark with a charge of -(1/3)e. ... Quark matter or QCD matter refers to any of a number of phases of matter whose degrees of freedom include quarks and gluons. ... A hadron, in particle physics, is a subatomic particle which experiences the nuclear force. ... A strange star or quark star is a hypothetical type of star composed of strange matter. ...


History of discoveries

The first direct observation of a neutron star in visible light. The neutron star being RX J185635-3754.

In 1932, Sir James Chadwick discovered the neutron as an elementary particle,[5] for which he was awarded the Nobel Prize in Physics in 1935. Image File history File links Size of this preview: 537 × 599 pixels Full resolution (650 × 725 pixel, file size: 87 KB, MIME type: image/jpeg) The first direct observation of a neutron star in visible light. ... Image File history File links Size of this preview: 537 × 599 pixels Full resolution (650 × 725 pixel, file size: 87 KB, MIME type: image/jpeg) The first direct observation of a neutron star in visible light. ... RX J185635-3754 (or RXJ185635-375) is a nearby neutron star. ... Sir James Chadwick, CH (20 October 1891 – 24 July 1974) was an English physicist and Nobel laureate who is best known for discovering the neutron. ... Hannes Alfvén (1908–1995) accepting the Nobel Prize for his work on magnetohydrodynamics [1]. List of Nobel Prize laureates in Physics from 1901 to the present day. ...


In 1933, Walter Baade and Fritz Zwicky proposed the existence of the neutron star,[6] only a year after Chadwick's discovery of the neutron. In seeking an explanation for the origin of a supernova, they proposed that the neutron star is formed in a supernova. Supernovae are suddenly appearing dying stars in the sky, whose luminosity in the optical might outshine an entire galaxy for days to weeks. Baade and Zwicky correctly proposed at that time that the release of the gravitational binding energy of the neutron stars powers the supernova: "In the supernova process mass in bulk is annihilated". If the central part of a massive star before its collapse contains (for example) 3 solar masses, then a neutron star of 2 solar masses can be formed. The binding energy E of such a neutron star, when expressed in mass units via the mass-energy equivalence formula E = mc², is 1 solar mass. It is ultimately this energy that powers the supernova. Wilhelm Heinrich Walter Baade (March 24, 1893 - June 25, 1960) was a German astronomer who emigrated to the USA in 1931. ... Fritz Zwicky (February 14, 1898 – February 8, 1974) was an American-based Swiss astronomer. ... For other uses, see Supernova (disambiguation). ... For other uses, see Galaxy (disambiguation). ... The gravitational binding energy of an object is the amount of energy required to accelerate every component of that object to the escape velocity of every other component. ... 15ft sculpture of Einsteins 1905 E = mc² formula at the 2006 Walk of Ideas, Germany In physics, mass-energy equivalence is the concept that all mass has an energy equivalence, and all energy has a mass equivalence. ...


In 1965, Antony Hewish and Samuel Okoye discovered "an unusual source of high radio brightness temperature in the Crab Nebula.[7]" This source turned out to be the Crab Nebula neutron star that resulted from the great supernova of 1054 CE. Antony Hewish (born Fowey, Cornwall, May 11, 1924) is a British radio astronomer who won the Nobel Prize for Physics in 1974 (together with fellow radio-astronomer Martin Ryle) for his work on the development of radio aperture synthesis and its role in the discovery of pulsars. ...


In 1967, Jocelyn Bell and Antony Hewish discovered regular radio pulses from the location of the Hewish and Okoye radio source. This pulsar, was later interpreted as originating from an isolated, rotating neutron star. The energy source of the pulsar is the rotational energy of the neutron star. The largest number of known neutron stars are of this type (See Rotation-powered pulsar). Dame Jocelyn Bell Burnell, DBE, FRS FRAS, Ph. ... Antony Hewish (born Fowey, Cornwall, May 11, 1924) is a British radio astronomer who won the Nobel Prize for Physics in 1974 (together with fellow radio-astronomer Martin Ryle) for his work on the development of radio aperture synthesis and its role in the discovery of pulsars. ... It has been suggested that Radio pulsar be merged into this article or section. ... It has been suggested that this article or section be merged into Pulsar. ...


In 1971, Riccardo Giacconi, Herbert Gursky, Ed Kellogg, R. Levinson, E. Schreier, and H. Tananbaum discovered 4.8 second pulsations in an X-ray source in the constellation Centaurus, Cen X-3. They interpreted this as resulting from a rotating hot neutron star. The energy source is gravitational and results from a rain of gas falling onto the surface of the neutron star from a companion star or the interstellar medium (See Accretion-powered pulsar). Riccardo Giacconi (born October 6, 1931) is an Italian-born American Nobel Prize-winning astrophysicist. ... This article is about the star grouping. ... Centaurus (Latin for centaur) was one of the 48 constellations listed by Ptolemy, and counts also among the 88 modern constellations. ... See also: Accretion (finance) Accretion is increase in size by gradual addition of smaller parts. ... Binary star A binary star system consists of two stars both orbiting around their barycenter. ... The interstellar medium (or ISM) is the name astronomers give to the tenuous gas and dust that pervade interstellar space. ... An X-ray pulsar is a neutron star with a powerful magnetic field that gives rise to regular X_ray pulses. ...


In 1974, Antony Hewish was awarded the Nobel Prize in Physics "for his decisive role in the discovery of pulsars" without Samuel Okoye and Jocelyn Bell who shared in the discovery. Antony Hewish (born Fowey, Cornwall, May 11, 1924) is a British radio astronomer who won the Nobel Prize for Physics in 1974 (together with fellow radio-astronomer Martin Ryle) for his work on the development of radio aperture synthesis and its role in the discovery of pulsars. ... Hannes Alfvén (1908–1995) accepting the Nobel Prize for his work on magnetohydrodynamics [1]. List of Nobel Prize laureates in Physics from 1901 to the present day. ... Jocelyn Bell Burnell (born Jocelyn Bell, 15 July 1943), British astrophysicist who discovered the first radio pulsars with her thesis advisor Antony Hewish. ...


Rotation

Neutron stars rotate extremely rapidly after their creation due to the conservation of angular momentum; like an ice skater pulling in his or her arms, the slow rotation of the original star's core speeds up as it shrinks. A newborn neutron star can rotate several times a second; sometimes, when they orbit a companion star and are able to accrete matter from it, they can increase this to several hundred times per second, distorting into an oblate spheroid shape despite their own immense gravity (an equatorial bulge). A millisecond pulsar (MSP), often referred to as recycled pulsar, is a pulsar with a rotational period in the range of about 1-10 milliseconds. ... Oblate also refers to a member of the Roman Catholic religious order of the Missionary Oblates of Mary Immaculate, or in some cases to a lay or religious person who has officially associated himself (or herself) with a monastic community such as the Benedictines for reasons of personal enrichment without... An equatorial bulge is a planetological term which describes a bulge which a planet may have around its equator, distorting it into an oblate spheroid. ...


Over time, neutron stars slow down because their rotating magnetic fields radiate energy; older neutron stars may take several seconds for each revolution.


The rate at which a neutron star slows down its rotation is usually constant and very small: the observed rates are between 10-10 and 10-21 second for each rotation. In other words, for a typical slow down rate of 10-15 seconds per rotation, then a neutron star now rotating in 1 second will rotate in 1.000003 seconds after a century, or 1.03 seconds after 1 million years.


Sometimes a neutron star will spin up or undergo a glitch, a rapid and unexpected increase of its rotation speed (of the same, extremely small scale as the constant slowing down). Glitches are thought to be the effect of a starquake: As the rotation of the star slows down, the shape becomes more spherical. Due to the stiffness of the 'neutron' crust, this happens as discrete events as the crust ruptures, similar to tectonic earthquakes. After the starquake, the star will have a smaller equatorial radius, and since angular momentum is conserved, rotational speed increases. Recent work, however, suggests that a starquake would not release sufficient energy for a neutron star glitch; it has been suggested that glitches may instead be caused by transitions of vortices in the superfluid core of the star from one metastable energy state to a lower one.[8]


Neutron stars may "pulse" due to particle acceleration near the magnetic poles, which are not aligned with the rotation axis of the star. Through mechanisms not yet entirely understood, these particles produce coherent beams of radio emission. External viewers see these beams as pulses of radiation whenever the magnetic pole sweeps past the line of sight. The pulses come at the same rate as the rotation of the neutron star, and thus, appear periodic. Neutron stars which emit such pulses are called pulsars. Magnetic lines of force of a bar magnet shown by iron filings on paper A magnet is an object that has a magnetic field. ... It has been suggested that Radio pulsar be merged into this article or section. ...


The most rapidly rotating neutron star currently known, PSR J1748-2446ad, rotates at 716 revolutions per second.[9] A recent paper reported the detection of an X-ray burst oscillation (an indirect measure of spin) at 1122 Hz from the neutron star XTE J1739-285.[10] However, at present this signal has only been seen once, and should be regarded as tentative until confirmed in another burst from this star. In astronomy, and in particular the study of pulsars, PSR J1748-2446ad is the fastest known spinning pulsar, at 716 Hz, the period being 0. ...


Subtypes

  • Neutron star
    • Radio-quiet neutron stars
    • Radio emitting
      • Single pulsars – general term for neutron stars that emit directed pulses of radiation towards us at regular intervals (due to their strong magnetic fields).
      • Binary pulsars
        • Accretion-powered pulsar ("X-ray pulsar")
          • X-ray burster – a neutron star with a low mass binary companion from which matter is accreted resulting in irregular bursts of energy from the surface of the neutron star.
          • Millisecond pulsar ("recycled pulsar")
      • Quark Star – a currently still hypothetical type of neutron star composed of quark matter, or strange matter. As of February 2007, there are three candidates.
      • Preon star – a currently still hypothetical type of neutron star composed of preon matter. As of 2007, there is no evidence for the existence of preons.

A radio-quiet neutron star is a neutron star that does not seem to emit radio emissions like most other neutron stars. ... It has been suggested that Radio pulsar be merged into this article or section. ... It has been suggested that this article or section be merged into Pulsar. ... Artists conception of a magnetar, with magnetic field lines A magnetar is a neutron star with an extremely powerful magnetic field, the decay of which powers the emission of copious amounts of high-energy electromagnetic radiation, particularly X-rays and gamma-rays. ... A soft gamma repeater is an astronomical object, now known to be a type of magnetar, which emits large bursts of gamma rays and X-rays at irregular intervals. ... Anomalous X-ray Pulsars (AXPs) are now widely believed to be magnetars—young, isolated, highly magnetized neutron stars. ... A binary pulsar is a pulsar with a binary companion, often another pulsar, white dwarf or neutron star. ... An X-ray pulsar is a neutron star with a powerful magnetic field that gives rise to regular X_ray pulses. ... X-ray bursters are a class of binary stars which have periodic outbursts luminous in X-rays. ... A millisecond pulsar (MSP), often referred to as recycled pulsar, is a pulsar with a rotational period in the range of about 1-10 milliseconds. ... A strange star or quark star is a hypothetical type of star composed of strange matter, or quark matter. ... A preon star is a hypothetical compact star made of preons, a group of theoretical subatomic particles that may compose quarks and leptons. ...

Giant nuclei

A neutron star has some of the properties of an atomic nucleus, including density, and being made of nucleons. In popular scientific writing, neutron stars are therefore sometimes described as giant nuclei. However, in other respects, neutron stars and atomic nuclei are quite different. In particular, a nucleus is held together by the strong force, while a neutron star is held together by gravity. It is generally more useful to consider such objects as stars. The nucleus of an atom is the very small dense region, of positive charge, in its centre consisting of nucleons (protons and neutrons). ... In physics a nucleon is a collective name for two baryons: the neutron and the proton. ... The strong nuclear force or strong interaction (also called color force or colour force) is a fundamental force of nature which affects only quarks and antiquarks, and is mediated by gluons in a similar fashion to how the electromagnetic force is mediated by photons. ... Gravity is a force of attraction that acts between bodies that have mass. ... This article is about the astronomical object. ...


See also

Timeline of white dwarfs, neutron stars, and supernovae Note that this list is mainly about the development of knowledge, but also about some supernovae taking place. ... A strange star or quark star is a hypothetical type of star composed of strange matter, or quark matter. ... Quark Matter refers to any of a number of phases of matter built out of quarks and gluons. ... Degenerate matter is matter which has sufficiently high density that the dominant contribution to its pressure arises from the Pauli exclusion principle. ... A preon star is a hypothetical compact star made of preons, a group of theoretical subatomic particles that may compose quarks and leptons. ... In particle physics, preons are postulated point-like particles, that are subparticles of quarks and leptons. ... Degenerate matter is matter which has sufficiently high density that the dominant contribution to its pressure arises from the Pauli exclusion principle. ... This article or section does not adequately cite its references or sources. ... Neutronium is a term used in science fiction and popular literature to refer to an extremely dense phase of matter composed primarily of neutrons. ... Degenerate matter is matter which has sufficiently high density that the dominant contribution to its pressure arises from the Pauli exclusion principle. ... Rotating radio transients (RRATs) are a newly discovered (as of 2006) type of radio pulsars. ... A radio-quiet neutron star is a neutron star that does not seem to emit radio emissions like most other neutron stars. ... It has been suggested that Radio pulsar be merged into this article or section. ... Artists conception of a magnetar, with magnetic field lines A magnetar is a neutron star with an extremely powerful magnetic field, the decay of which powers the emission of copious amounts of high-energy electromagnetic radiation, particularly X-rays and gamma-rays. ... A millisecond pulsar (MSP), often referred to as recycled pulsar, is a pulsar with a rotational period in the range of about 1-10 milliseconds. ... Neutron stars in fiction // The idea of a superdense star composed of neutrons was proposed in 1933. ...

References

  1. ^ 8.4x10^16kgm-3 derives from mass 2.8x10^30kg / volume of star of radius 20km;1x10^18kgm-3 derives from mass 4.2x10^30kg / volume of star radius 10km
  2. ^ Calculating a Neutron Star's Density. Retrieved on 2006-03-11. NB 3×1017 kg/m³ is 3×1014 g/cm³
  3. ^ Introduction to neutron stars. Retrieved on 2007-11-11.
  4. ^ 5 ml of a 10 km radius neutron star's average density material masses 5 cm3 x 1.1 x 10^12kgcm-3, or 5.5x10^12kg or 5500000000 tonne, about 15 times the total mass of the human world population;
    5 ml of a 20 km radius star would mass 5 cm3 x 8.35 x 10^10kgcm-3, or about 400 million tonne or about the mass of all humans
  5. ^ Chadwick, James. "On the possible existence of a neutron". Nature 129: 312. 
  6. ^ Baade, Walter and Zwicky, Fritz. "Supernovae and Cosmic rays". Phys. Rev. 46. 
  7. ^ Hewish and Okoye. "Evidence of an unusual source of high radio brightness temperature in the Crab Nebula". Nature 207: 59. 
  8. ^ Alpar, M Ali (Jan 1, 1998). Pulsars, glitches and superfluids. Physicsworld.com.
  9. ^ http://arxiv.org/abs/astro-ph/0601337
  10. ^ http://www.journals.uchicago.edu/cgi-bin/resolve?id=doi:10.1086/513270
  • ASTROPHYSICS: ON OBSERVED PULSARS. scienceweek.com. Retrieved on 6 August, 2004.
  • Norman K. Glendenning, R. Kippenhahn, I. Appenzeller, G. Borner, M. Harwit (2000). Compact Stars, 2nd ed. 
  • Evidence for 1122 Hz X-Ray Burst Oscillations from the Neutron-Star X-Ray Transient XTE J1739-285. ApJL. Retrieved on 28 February, 2007.

Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 70th day of the year (71st in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ... is the 315th day of the year (316th in leap years) in the Gregorian calendar. ...

External links

Wikimedia Commons has media related to:
Neutron star
  • Introduction to neutron stars
  • "NASA Sees Hidden Structure Of Neutron Star In Starquake". SpaceDaily.com. April 26 2006
  • "Mysterious X-ray sources may be lone neutron stars". New Scientist.
  • "Massive neutron star rules out exotic matter". New Scientist. According to a new analysis, exotic states of matter such as free quarks or BECs do not arise inside neutron stars.
  • "Neutron star clocked at mind-boggling velocity". New Scientist. A neutron star has been clocked traveling at more than 1500 kilometres per second.

  Results from FactBites:
 
Distortions Paper Neutron Star Trip Description with GIFs (1180 words)
This neutron star has a hard equation of state [27] for its internal matter, the result of which is that the matter in the star is not compressed enough to have either a photon sphere or an event horizon.
At 100 R_S (420 km) from the neutron star as depicted in Fig.
Stars that would have been seen to approach this point in the absence of strong gravity now have images that are seen to approach the circle in the presence of strong gravity.
neutron star (593 words)
A neutron star, with a mass of 1.4 to 3 solar masses, forms from the collapsing core of a massive star immediately following the star's exhaustion of its fusion energy reserves.
Left behind is a rapidly spinning neutron star which has a strong magnetic field with poles that are usually aligned with the pole's of the star's rotation.
Its core consists mainly of densely-packed neutrons, with a sprinkling of protons and an equal number of electrons, in a liquid-like state known as neutronium.
  More results at FactBites »

 
 

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