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The possible disappearance of a massive star in the galaxy PHL 293B

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Re: The possible disappearance of a massive star in the galaxy PHL 293B

#31

Post by marcosdumay »

ctchocula wrote: post #3
antognini wrote: post #2

To provide a little bit of context for this work, one of the open questions in astronomy is how core collapse supernovae work. Computational scientists have struggled for a long time to get simulations of core collapse to explode. Typically to get an explosion they have to artificially insert a "piston" somewhere in the system that kicks the system outwards during the collapse and triggers the shock wave. Over maybe…

IANAP and this could be a bit of a stretch, but could the disappearance of the star been caused by the completion of a Dyson sphere around it?

A Dyson sphere/swarm has huge emissions on the infrared band that would be easy to detect on the tens of millions of light years distance.

Edit: AFAIK, this group didn't look for that. But the fact that nobody ever found one is telling.

Re: The possible disappearance of a massive star in the galaxy PHL 293B

#32

Post by MichaelMoser123 »

antognini wrote: post #2

To provide a little bit of context for this work, one of the open questions in astronomy is how core collapse supernovae work. Computational scientists have struggled for a long time to get simulations of core collapse to explode. Typically to get an explosion they have to artificially insert a "piston" somewhere in the system that kicks the system outwards during the collapse and triggers the shock wave. Over maybe…

here it says that such an event should create detectable gravitational waves https://aasnova.org/2019/07/05/can-we-detect-gravitational-w... The article mentions that we might get good enough detectors in some ten years already.

Re: The possible disappearance of a massive star in the galaxy PHL 293B

#33

Post by Someone »

blendergeek wrote: post #28
Cthulhu_ wrote: post #9

Earlier quoted context omitted.

It would be; first, spheres are unrealistic because of the stresses involved, so you'd be looking at a dyson swarm instead, and second, (and this is with sci-fi glasses on), even advanced civilizations would need many years to build one, so there would be a gradual fading instead.

It could be the result of the closing of the dyson sphere/swarm. If the dyson sphere/swarm is built like giant Venetian blinds, it could work.

Easier: if they build the frame for the sphere first, then added (gigantic) panels one at a time, a part filled with panels might have moved into our line of sight.

Re: The possible disappearance of a massive star in the galaxy PHL 293B

#34

Post by mkl »

luspr wrote: post #24
gnur wrote: post #10

Earlier quoted context omitted.

If you are into these kinds of mysteries, I highly recommend reading Pandora's Star by Peter F Hamilton. (even more so if you want to spend a few days reading this epic space opera)

I only read Pandora's Star so far, but I really liked the fact that it was a rather optimistic vision of the future. Humanity had colonies on dozens or hundreds of planets, and due to life extension people were basically immortal and could even choose the shape of their body.

Definitely read the sequel Judas Unchained. Those books are probably my favourite novels.

For more Peter F Hamilton optimistic future of humanity, see the Night's Dawn trilogy.

Re: The possible disappearance of a massive star in the galaxy PHL 293B

#36

Post by mkl »

codeulike wrote: post #29

This sounds like the plot of Pandoras Star by Peter F Hamilton At the farthest edge of the Commonwealth, astronomer Dudley Bose observes the impossible: Over one thousand light-years away, a star... vanishes. It does not go supernova. It does not collapse into a black hole. It simply disappears. Lets hope its not the [[SPOILER]]

Or Vernor Vinge's A Deepness in The Sky, which is also excellent.

Re: The possible disappearance of a massive star in the galaxy PHL 293B

#37

Post by JoeAltmaier »

Someone wrote: post #33
blendergeek wrote: post #28

Earlier quoted context omitted.

It could be the result of the closing of the dyson sphere/swarm. If the dyson sphere/swarm is built like giant Venetian blinds, it could work.

Easier: if they build the frame for the sphere first, then added (gigantic) panels one at a time, a part filled with panels might have moved into our line of sight.

Or maybe they built them all in a higher orbit spaced apart, then simultaneously decelerated them all so they fell as one into a Dyson sphere! Have to have some kind of process, why not that one?

Re: The possible disappearance of a massive star in the galaxy PHL 293B

#38

Post by metalliqaz »

antognini wrote: post #2

To provide a little bit of context for this work, one of the open questions in astronomy is how core collapse supernovae work. Computational scientists have struggled for a long time to get simulations of core collapse to explode. Typically to get an explosion they have to artificially insert a "piston" somewhere in the system that kicks the system outwards during the collapse and triggers the shock wave. Over maybe…

Great comment, thank you.

It is very informative but I especially admire your ability to communicate so clearly about a complex topic. I wish I could do that.

Re: The possible disappearance of a massive star in the galaxy PHL 293B

#39

Post by eru »

andyjohnson0 wrote: post #11

So today I learned that we have the ability to notice when a single star (possibly) disappears from a galaxy 75 million light years away. A small thing, but also a rather wonderful example of what we're capable of.

It was a particularly massive and bright star, though.

Still a great achievement!

Re: The possible disappearance of a massive star in the galaxy PHL 293B

#40

Post by vagab0nd »

antognini wrote: post #2

To provide a little bit of context for this work, one of the open questions in astronomy is how core collapse supernovae work. Computational scientists have struggled for a long time to get simulations of core collapse to explode. Typically to get an explosion they have to artificially insert a "piston" somewhere in the system that kicks the system outwards during the collapse and triggers the shock wave. Over maybe…

Thanks for the great explanation.

Are we tracking the spectra of everything visible in the sky? How much data is that?

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