Spherical Symmetry/Simultaneity of Supernova Explosions

In summary: So the upper limit on the time interval would likely depend on the size of the progenitor star. In summary, the timing of a supernova explosion does not have tight constraints on its simultaneity and sphericity like a nuclear weapon. The explosion mechanism is not well understood and can develop over a span of minutes or hours, with the upper limit likely depending on the size of the star. Asymmetry is expected due to differential rotation, but it may be hard to detect as our observations are only from one direction. There are no successful models of symmetric supernovae, indicating that they are likely asymmetric in nature.
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Islam Hassan
If the timing of detonation of nuclear weapons’ numerous implosive lenses must to be kept to within a microsecond or so in order to avoid asymmetrical detonation, does the timing of a supernova explosion similarly have tight constraints on its simultaneity and hence the sphericity of its ultimate cataclysmic implosion/explosion?

What are these constraints estimated to be, and are they occasionally breached? Have we observed asymmetric —or slightly asymmetric— supernova explosions?IH
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Above should help. The core is essentially spherical, so there is no reason to expect anything else. However our observations are from one direction, so asymmetry may be hard to detect.
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There's going to be asymmetry due to differential rotation - varying angular momentum with angle from the equator. Look at the Crab nebula - it's somewhat misshapen and oblong.
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As far as we know, supernovae are asymmetric. There is no models of symmetric supernovae that provide a) an explosion and b) a remnant. Since we see both, we know the symmetric models are wrong.
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To explain further - We still don't have successful models of type II supernova explosion mechanisms, so we don't know how they explode. Don Lamb at the University of Chicago was able to produce a successful model of a carbon detonation supernove - one produced by an accreting white dwarf star - but only if the explosion originated off-center.
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If the numerous implosive lenses on a nuclear weapon typically have to detonate within less than a microsecond, do we have an estimate of the ‘detonation’ interval window for supernovae?IH
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Islam Hassan said:
If the numerous implosive lenses on a nuclear weapon typically have to detonate within less than a microsecond, do we have an estimate of the ‘detonation’ interval window for supernovae?IH
The explosion mechanism for a supernova is not the same as for a nuclear weapon. The core of the massive star that forms the supernova turns into a neutron star that doesn't detonate, so the timing of the infall of the outer layers of the star is less critical for production of the explosion. Indeed, we're not sure if the outer layers of the star infall at all before the explosion occurs.
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Thanks for all your answers. Conceivably then, could a supernova explosion develop fully over a span of minutes or hours even? Would there theoretically be an upper limit on this time interval?IH
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The collapse of the stellar core to becoming a neutron star occurs on a freefall timescale and takes only a matter of seconds! Observations of neutrinos coming from the core of Supernova 1987a came several hours before the light signal from the event was observed, so the explosion developed over the span of a few hours. Presumably the more massive the star, the longer the interval for the explosion to develop.
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1. What is spherical symmetry in the context of supernova explosions?

Spherical symmetry refers to the symmetry of a spherical shape, where all points on the surface are equidistant from the center. In the context of supernova explosions, it refers to the explosion occurring uniformly in all directions.

2. How does spherical symmetry affect the appearance of a supernova explosion?

Due to spherical symmetry, the explosion appears as a round, expanding shell of gas and radiation. This is in contrast to other types of explosions, such as asymmetric ones, which can result in more irregular and elongated shapes.

3. Why is it important to study the simultaneous nature of supernova explosions?

Studying the simultaneous nature of supernova explosions can provide insight into the physical processes involved in the explosion, such as the energy release and the propagation of shock waves. It can also help us understand the evolution and fate of the star that exploded.

4. How do scientists determine the simultaneity of a supernova explosion?

Scientists use various methods to determine the simultaneity of a supernova explosion, such as observing the explosion from different angles and measuring the arrival times of the explosion's light and other forms of radiation. They can also use computer simulations to model the explosion and determine the timing of different events.

5. What can we learn from studying the spherical symmetry and simultaneity of supernova explosions?

Studying these aspects of supernova explosions can help us better understand the physics behind these powerful events and the properties of the stars that undergo them. It can also contribute to our understanding of the larger universe and the role of supernovae in its evolution.

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