APOD: Supernova Discovered in Nearby M101... (2023 May 22)

[AVAO]

What about the new supernova in M101, SN 2023ifx? Well... it looks a bit on the faint side to me. Of course, it is still brightening.

Indeed. Just imaging it right now. It's currently 20 times brighter than the core of M101!
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m101_2023.05.23.jpg

I second Ann's "wow!" Thanks for sharing this picture! (I also like how it brings out how thick and massive M101 is) - I wonder: what is the size of the area covered by the supernova? If that bright spot were instead, say, a star cluster, what would its dimension approximately be?

...Nice area...

https://live.staticflickr.com/65535/529 ... bcaf_o.jpg
jac berne (flickr)

[VictorBorun]

If only we could add neutrino and gravitation wave signals…

Imagine a scenario

1) where SN 2023ixf is first forming two or three neutron stars that then spiral down and form a black hole

2) where some yet-to-be-discovered process generate some dark matter particles helping to shed energy and spin

3) where a two neutron stars in a blink of eye merge, but having co-directional spins have to pinch the space-time fabric, fire a one-direction graviwaves packet and recoil so strongly, that the emerged black hole is kicked out of the supernova remnant and first out of the supernova flash cloud

[Chris Peterson]

If only we could add neutrino and gravitation wave signals…

Imagine a scenario

1) where SN 2023ixf is first forming two or three neutron stars that then spiral down and form a black hole

2) where some yet-to-be-discovered process generate some dark matter particles helping to shed energy and spin

3) where a two neutron stars in a blink of eye merge, but having co-directional spins have to pinch the space-time fabric, fire a one-direction graviwaves packet and recoil so strongly, that the emerged black hole is kicked out of the supernova remnant and first out of the supernova flash cloud

While such observations would be great, this particular event involves a type II core collapse supernova, which isn't associated with a binary precursor.

[VictorBorun]

If only we could add neutrino and gravitation wave signals…

Imagine a scenario

1) where SN 2023ixf is first forming two or three neutron stars that then spiral down and form a black hole

2) where some yet-to-be-discovered process generate some dark matter particles helping to shed energy and spin

3) where a two neutron stars in a blink of eye merge, but having co-directional spins have to pinch the space-time fabric, fire a one-direction graviwaves packet and recoil so strongly, that the emerged black hole is kicked out of the supernova remnant and first out of the supernova flash cloud

While such observations would be great, this particular event involves a type II core collapse supernova, which isn't associated with a binary precursor.

I was trying to say that a collapse may form a neutron star binary inside the collapsing stellar core, in a tight orbit in a dense disk or ring.
Of course, the progenitor has to possess enough mass for all, like 10 suns

[Chris Peterson]

If only we could add neutrino and gravitation wave signals…

Imagine a scenario

1) where SN 2023ixf is first forming two or three neutron stars that then spiral down and form a black hole

2) where some yet-to-be-discovered process generate some dark matter particles helping to shed energy and spin

3) where a two neutron stars in a blink of eye merge, but having co-directional spins have to pinch the space-time fabric, fire a one-direction graviwaves packet and recoil so strongly, that the emerged black hole is kicked out of the supernova remnant and first out of the supernova flash cloud

While such observations would be great, this particular event involves a type II core collapse supernova, which isn't associated with a binary precursor.

I was trying to say that a collapse may form a neutron star binary inside the collapsing stellar core, in a tight orbit in a dense disk or ring.
Of course, the progenitor has to possess enough mass for all, like 10 suns

I can't think of any reason that a core collapse would form a binary neutron star.

[VictorBorun]

While such observations would be great, this particular event involves a type II core collapse supernova, which isn't associated with a binary precursor.

I was trying to say that a collapse may form a neutron star binary inside the collapsing stellar core, in a tight orbit in a dense disk or ring.
Of course, the progenitor has to possess enough mass for all, like 10 suns

I can't think of any reason that a core collapse would form a binary neutron star.

everywhere you look many stars and multiple stellar systems form in a random cloud once the gravitation overcomes the pressure.
Why not mirror it, in a rapid mode, where a massive star core collapses once the fuel is exhausted and the pressure loses to the gravitation?

[Chris Peterson]

I was trying to say that a collapse may form a neutron star binary inside the collapsing stellar core, in a tight orbit in a dense disk or ring.
Of course, the progenitor has to possess enough mass for all, like 10 suns

I can't think of any reason that a core collapse would form a binary neutron star.

everywhere you look many stars and multiple stellar systems form in a random cloud once the gravitation overcomes the pressure.
Why not mirror it, in a rapid mode, where a massive star core collapses once the fuel is exhausted and the pressure loses to the gravitation?

The dynamics are radically different. Stellar systems form from slow viscous planar processes. A supernova is a rapid (relativistic) spherical collapse.

[VictorBorun]

I can't think of any reason that a core collapse would form a binary neutron star.

everywhere you look many stars and multiple stellar systems form in a random cloud once the gravitation overcomes the pressure.
Why not mirror it, in a rapid mode, where a massive star core collapses once the fuel is exhausted and the pressure loses to the gravitation?

The dynamics are radically different. Stellar systems form from slow viscous planar processes. A supernova is a rapid (relativistic) spherical collapse.

If the collapse is spherical, the spin of the progenitor transfers to one neutron star, but it can not take that much, can it? Mostly the spin has to be shed off in a massive blow up.

But if a ring forms in the collapsing stellar core and the ring breaks into 2 or 3 neutron stars, the spin of the progenitor transfers to the their orbital spin, and that can absorb much more of the mass and spin. As the 2 or 3 NSs feed, their total mass grow and the gravitation pull to the centre grows like mass*mass, so the acceleration grows like mass and the square of the orbiting velocity grows like mass; it lets the NSs take more and more of the spin.

Well, if they are 3, then the least massive is eventually kicked off carrying away the spin and the other 2 finally merge. There is got to be a runaway NS then.

[Chris Peterson]

everywhere you look many stars and multiple stellar systems form in a random cloud once the gravitation overcomes the pressure.
Why not mirror it, in a rapid mode, where a massive star core collapses once the fuel is exhausted and the pressure loses to the gravitation?

The dynamics are radically different. Stellar systems form from slow viscous planar processes. A supernova is a rapid (relativistic) spherical collapse.

If the collapse is spherical, the spin of the progenitor transfers to one neutron star, but it can not take that much, can it? Mostly the spin has to be shed off in a massive blow up.

But if a ring forms in the collapsing stellar core and the ring breaks into 2 or 3 neutron stars, the spin of the progenitor transfers to the their orbital spin, and that can absorb much more of the mass and spin. As the 2 or 3 NSs feed, their total mass grow and the gravitation pull to the centre grows like mass*mass, so the acceleration grows like mass and the square of the orbiting velocity grows like mass; it lets the NSs take more and more of the spin.

Why does the spin need to be "shed off"? The explosion is a bounce. I don't see any mechanism, given a substantially spherically symmetric event, for there to somehow be two cores produced.

[VictorBorun]

The dynamics are radically different. Stellar systems form from slow viscous planar processes. A supernova is a rapid (relativistic) spherical collapse.

If the collapse is spherical, the spin of the progenitor transfers to one neutron star, but it can not take that much, can it? Mostly the spin has to be shed off in a massive blow up.

But if a ring forms in the collapsing stellar core and the ring breaks into 2 or 3 neutron stars, the spin of the progenitor transfers to the their orbital spin, and that can absorb much more of the mass and spin. As the 2 or 3 NSs feed, their total mass grow and the gravitation pull to the centre grows like mass*mass, so the acceleration grows like mass and the square of the orbiting velocity grows like mass; it lets the NSs take more and more of the spin.

Why does the spin need to be "shed off"? The explosion is a bounce. I don't see any mechanism, given a substantially spherically symmetric event, for there to somehow be two cores produced.

because a compact thing like neutron star or black hole has a small radius, and spin is mass*velocity*radius

[Chris Peterson]

If the collapse is spherical, the spin of the progenitor transfers to one neutron star, but it can not take that much, can it? Mostly the spin has to be shed off in a massive blow up.

But if a ring forms in the collapsing stellar core and the ring breaks into 2 or 3 neutron stars, the spin of the progenitor transfers to the their orbital spin, and that can absorb much more of the mass and spin. As the 2 or 3 NSs feed, their total mass grow and the gravitation pull to the centre grows like mass*mass, so the acceleration grows like mass and the square of the orbiting velocity grows like mass; it lets the NSs take more and more of the spin.

Why does the spin need to be "shed off"? The explosion is a bounce. I don't see any mechanism, given a substantially spherically symmetric event, for there to somehow be two cores produced.

because a compact thing like neutron star or black hole has a small radius, and spin is mass*velocity*radius

Yes. And they often have absurdly high spin rates as a consequence. Because angular momentum is conserved, and because such spin rates, hundreds of revolutions per second, don't disrupt the body.