Type II Supernova
The most famous Type II supernova, SN 1987A, was also a very unusual one. Here we see a picture taken before (right) and after (left) the explosion, which clearly shows the progenitor (Sanduleak -69o 202) of the supernova.
The most widely-known type of exploding star, a Type II supernova begins with a yellow star similar to our own sun, but with ten times the mass.
Type II supernovae
The structure of all stars is determined by the battle between gravity and radiation pressure arising from internal energy generation.
type II supernova
the explosion of a massive star that occurs when its core runs out of nuclear fuel; these explosions leave behind a neutron star or a black hole
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Type II supernova One possible explosive death of a star, in which the highly evolved stellar core rapidly implodes and then explodes, destroying the surrounding star.
Type II Supernova (SNII) - Explosive death of a >4 Msun star. Type II supernovae (SNII) were recognized as a distinct type of supernova in the early 1940s.
Type II Supernova - An extremely energetic explosion that occurs when the core of a massive star collapses, probably producing a neutron star or black hole ...
Type II supernovas involve massive stars that burn their gases out within a few million years. If the star is massive enough, it will continue to undergo nucleosynthesis after the core has turned to helium and then to carbon.
Type II supernova (eg SN 1987A)
total energy 10 46 Joules (gravity origin)
energy emerges : 99% neutrinos, 1% kinetic, 0.01% light
neutrino burst detected from SN 1987A
light outshines galaxy for a week ...
Type II supernovae occur in the arms of spiral galaxies. Typical rates for these explosions suggest that one should be visible in a galaxy every 25-50 years. None has been seen in our Milky Way since Kepler's supernova of 1604.
A type II supernova just went off in the Andromeda galaxy. These supernova usually reach an absolute magnitude of around -17 when they are their brightest. The Andromeda galaxy is 730,000 pc away.
[4.1] TYPE II SUPERNOVAS / SUPERNOVA 1987A
[4.2] NOVAS, DWARF NOVAS, & TYPE I SUPERNOVAS
[4.3] GAMMA-RAY BURSTERS ...
Of the Type II supernovae with unusual features in their spectra, Type IIn supernovae may be produced by the interaction of the ejecta with circumstellar material.
What gives a Type II supernova its energy?
[A] Nuclear Fusion
[B] Nuclear Fission
[C] TNT
[D] Gravity ...
The stars that make Type II supernovae, on the other hand, probably are born in a galaxy's spiral arms -- regions that are populated by lots of young, bright stars -- and don't live long enough to wander from their birthplaces.
Type II supernovae happen in single star systems (or at least far enough away from any companion star to retain their hydrogen outer layers) and have strong hydrogen emission lines. Type II create most of the oxygen found in the interstellar medium.
Through a process that is not completely understood, some of the gravitational potential energy released by this core collapse is converted into a Type Ib, Type Ic, or Type II supernova.
Astronomers predict that Betelgeuse will ultimately undergo a type II supernova explosion although it is possible that the mass is low enough for Betelgeuse to leave a rare oxygen-neon white dwarf.
In an independent study, a team of researchers from Hiroshima University in Japan argue that SN 2005E's progenitor star was more massive - between 10 and 12 solar masses - and that it underwent a core-collapse similar to a Type II supernova.
Supernova (More accurately, type II supernova.) When a star burns up all its fuel, it collapses and the released gravitational energy blows off its top layers, creating a supernova explosion. What remains of the star depends on its mass.
It has been applied to Type II supernovae, which are massive stars with a hydrogen rich envelope that explode when their cores collapse to from neutron stars.
White Dwarfs are the remnants of stars that were massive enough to stay alive using nuclear fusion in their cores, but not massive enough to blow apart in a Type II supernova. When stars like our own sun die they will become white dwarfs.
Additional observations soon showed that it is a "Type II supernova," resulting from the explosion of a massive, hydrogen-rich star at the end of its life.
Massive stars very rapidly become Type II supernovae, spewing a wide range of elements back into the clouds from which they form, whereas close, intermediate-mass binaries may evolve into Type I supernovae, favoring production of iron-group elements.
Type II supernovae are more common: Tammann (1974) finds that Type II supernovae occur in our Galaxy at the rate of 0.01 to 0.05 per year.
In a few hours the shock wave hits the surface of the star and we see the star explode as a Type II supernova. In a matter of days the star brightens by about a factor of 100 million, becoming for a brief time as bright as an entire galaxy.
A Dictionary of Astronomy entry for Type I, Type II supernova
A Dictionary of Astronomy entry for supernova remnant
A Dictionary of Astronomy entry for Supernova 1987A
A Dictionary of Astronomy entry for supernova ...
A neutron star is a type of compact star that can result from the gravitational collapse of a massive star during a Type II supernova, Type Ib and Ic supernovae supernova event....
, created during the explosion.
Also, the outer layers of the star will be thrown off to space. This is a Type II supernova explosion. (In contrast, a type I supernova is an ordinary nova explosion that are strong enough to destroy the white dwarf at the center.) ...
The exact time delay is unknown, but for a Type II supernova, astronomers expect the neutrino flood to be released seconds after the stellar core collapse, while the first electromagnetic signal may be hours or days later.
The supernova is caused by the collapse of the white dwarf to a neutron star when its mass exceeds the Chandrasekhar limit. Type II supernovae are the end points in the evolution of stars with masses seven more times that of the Sun.
 See also: Supernova, Star, Mass, Sun, Energy
  
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