Supernovae are the result of a star dying in an explosion

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Why does a supernova explode

This is really bugging me. When you look up some educational text about stars life, this is what you find out: Gravity creates the temperature and pressure to start fusion reactions. The fusion ...
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Can neutrino detectors tell what direction the neutrinos came from?

I was reading this question and got to thinking. Can neutrino detectors give us any clue where the neutrinos came from or when a supernova may occur?
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What is the percentage of stars that are massive enough to end their lives in a supernova?

I have been searching for the percentage of stars that are massive enough to end their lives as a supernova but couldn't get any result. As far as I know, a star has to be at least 8 times more ...
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What happens to the neighboring star of a type Ia supernova?

Supernovae of type "Ia" are those without helium present, but with evidence of silicon present in the spectrum. The most accepted theory is that this type of supernova is the result of mass accretion ...
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The delay between neutrinos and gammas in a supernova, and the absolute mass scale of neutrinos

In a supernova explosion (of some type), there is a huge amount of neutrinos and gamma rays produced by a runaway nuclear reaction at the stellar core. In a recent comment, dmckee noted that the ...
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Near-Earth supernova

There are 51 stars within 17 light years of the Earth (source). If one of these stars was to become a supernova, how would they effect the Earth? I have read the Wikipedia article Near-Earth ...
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How to calculate the kinetic energy of supernova ejecta?

I believed I could use $0.5\times M_{ej} V_{ej}^2$, with $M_{ej}$ being the ejected mass and $V_{ej}$ being the velocity of the ejected mass. But I noticed in this and this that the the mean velocity ...
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If neutrinos travel faster than light, how much lead time would we have over detecting supernovas?

In light of the recent story that neutrinos travel faster than photons, I realize the news about this is sensationalistic and many tests still remain, but let's ASSUME neutrinos are eventually proven ...
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Death by neutrinos - polonium go home

In Randall Munroe's What If? He is calculating the Lethal Neutrinos dose. If you observed a supernova from 1 AU away—and you somehow avoided being being incinerated, vaporized, and converted to ...
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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 ...
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Why does gravitational collapse occur suddenly in a supernova progenitor?

I was reading the Wikipedia article on Supernovae, and it says that one of the reasons why a supernova occurs is due to sudden gravitational collapse when the core of the star has little fusable ...
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Do supernovae produce an appreciable amount of lithium?

David Z's answer to this question got me wondering - is any appreciable amount of lithium produced as the result of a supernova explosion, either by fusion (which seems unlikely to me, but I don't ...
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How is the distance to a $\gamma \mathrm{-ray}$ burst (GRB) measured in just a few days?

Recently the Fermi Gamma-ray Space Telescope recorded the most energetic Gamma Ray burst (GRB 130427A) yet observed with a peak $\gamma \mathrm{-ray}$ energy of $94\, \mathrm{GeV}$. Various sources ...
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The Opera Neutrino Experiment and the Supernova 1987

So this probably stems from my massive ignorance about post-Newtonian physics but the supernova results of 1987 which measured neutrinos arriving 3 hours before the light from the supernova have been ...
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Is there any chance we could eventually observe the supernova of the first (Population III) stars

In an answer to my previous question about the first stars it was stated they probably formed at Z=20 to Z=60 and may have had a mass between tens to 100s to 1000s of times the mass of the Sun. Given ...
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Neutrino Speed in Supernova

I've read that neutrinos in supernova can be affected by "neutrino refraction." Is this analagous to the refraction of light, and if so, is the speed of these neutrinos similarly reduced from their ...
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Estimating the expansion of the universe using light from supernova

I understand that you can tell how far light has traveled by the measuring redshift but how accurate is this and could it be effected by anything like radiation from the sun it must be fairly accurate ...
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What is the heaviest element possible produced in a supernova?

So, I would imagine this question would have been asked here long ago but the suggested questions and Google is really letting me down now. So, as far as I can tell Plutonium is the heaviest naturally ...
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Elements of a Planet reveals nearby supernova remnant?

During a random reading through this site, I found this one: Origin of elements heavier than Iron (Fe) There was an answer mentioning that "the formation of many elements in earth was due to ...
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Remnant of a supernova

A supernova remnant is the structure resulting from the explosion of a giant star. The supernova remnant is surrounded by an expanding shock wave that is formed from material ejected by the explosion ...