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2D Supernova (Praxis fx validated! lol)

O

ozzfloyd

Captain
Captain
https://www.ruckusfactory.com/video.../channel/309/hfwhgocsgrrueq3ejv3uivjxgjytmtsc

Star Explodes in Aspherical 2D Shape in Space Challenging ‘Our Preconceptions of How Stars Might Explode’
Apr 3, 2023, 05:26 AM | 01:22

Fast blue optical transients, or FBOTs are energetic explosions in space, but they are also extremely rare. In fact only 5 have ever been detected to date, but the most recent one that occurred around 180 million light-years away is even stranger. That’s because it didn’t explode spherically like, well, every other explosion ever. This on seems to have exploded in a 2D disk.
 
So the Stargate explosion and the Death Star remix got it right after all.

In general---a disk shaped explosive makes a cylinder---and a cylinder shaped explosive blows out into a disk.

Maybe the body's spin has some influence.
 
For some reason, the video won't play in my browser, but I assume it's referring to "the Cow" observed in 2018.

Extremely flat explosion dubbed 'the Cow' defies explanation | Live Science

No-one has any real idea what causes fast blue optical transients, but they are extremely powerful compared even to superluminous supernovae, themselves ten times more luminous than type II (core collapse) supernovae, and we understand superluminous supernovae poorly. I don't know why the explosion would be concentrated into a disc rather than a shell or axial jets, but if I had to hypothesise, I'd guess that direct collapse into a rapidly rotating Kerr or even Kerr-Newman black hole might be involved where the axial jets rapidly precess at a large angle due to the torque applied by a nearby massive stellar object and the jets are fuelled by material pulled off that object. However, explaining the extremely high luminosity of FBOTs is difficult. Here's another explanation:

Dying stars’ cocoons might explain fast blue optical transients - Northwestern Now

However, I don't know if this model can explain events such as "the Cow".
 
Some chatter here:
https://forum.cosmoquest.org/forum/science-and-space/astronomy/142950-#post3575766

Now…how fast would a neutron have to spin for Earth normal gravity at the equator?

Gravity is highest at the poles that want to race towards each other—and you get a disk blow-out…that’s my best guess.

For our Milky Way core’s matter expulsion…a smaller black hole orbiting just above Sgr A* slingshots a thin accretion disk. Close to the smaller black hole’s event horizon, the gravity of the two BHs cancel out…and you get a non polar jet that spirals out…another type of disk? What goes on in Saturns ring…but on steroids perhaps…

Beyond that, I got nothin’
 
The surface gravity of a typical neutron star is about 10^11 (one hundred billion) times that of the Earth - g' = 10^12 m/s^2 roughly. The rotational velocity to reduce the gravitational acceleration to g = 10 m/s^2 (actually 9.81 m/s^2 but let's round it up a little) is v = √(10^12*r), where a typical neutron star radius is 1.5*10^4m (15 km), so v = √(10^12*1.5x10^4) = √(1.5*10^16) = 1.2*10^8 m/s. This is roughly the same as the orbital velocity at the surface and is just over one third of the speed of light. The neutron star would be rotating 1.2*10^8/1.5*10^4*2*π times per second or 1,270 times per second. The fastest known rotating neutron stars rotate at about 1,000 times per second. Current theories of neutron star structure predict they break apart if they spin at a rate of more than 1,500 rotations per second. Above 1,000 rotations per second, they lose energy by gravitational radiation faster than any accretion process could speed them up. So it's possible that the net acceleration at the equator could be around 10 m/s^2 for a very fast spinning neutron star, but the high magnetic field strength (10^4 to 10^11 tesla, magnetars are 10^8 tesla or higher and are definitely deadly; 16 tesla is sufficient to levitate a diamagnetic object such as a frog) and temperature (600,000 K, so about 3 nanometre soft X-rays by Wien's law) would likely make things very uncomfortable and not survivable for very long. The tidal forces due to the gravitational field gradient would in any case cause spaghettification. The models of neutron star structure contain quite a high degree of uncertainty as the relevant equations of state are hypotheses and the effects of general relativity must be considered.
 
New post rather than editing my last one...

I've had a further thought that a fast blue optical transient like the Cow might be similar to the formation of a Thorne–Żytkow object (TŻO) - the result of a neutron star spiralling into the core of a red giant or a red supergiant - except that a rapidly rotating black hole is involved in the collision rather than a neutron star. The axial jets of the black hole could sweep out a disc if the black hole rapidly precesses through a large angle. The end result would likely be a black hole and not a TŻO.

ETA: Excellent video from Anton Petrov about FBOTs and the Cow.

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ETA2: Another video from Anton about why certain objects can be brighter than the Eddington limit. The explanation proposed is that very intense magnetic fields, such as those around magnetars, squeeze atoms so much that their cross-section to X-ray photons is reduced by two orders of magnitude.

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