3 ms·

At least they got to see it before Betelgeuse went supernovae. Do we have examples of the results of the companion star when the main star lets go?

dontlikeyoueith 1y ago
Wouldn't all Type Ia supernova be examples of at least one possible end state of such an event? https://science.nasa.gov/resource/type-ia-supernova/ https://science.nasa.gov/resource/type-ia-supernova/ The larger star explodes first in a Type II supernova, becomes a Type Ia.
- dylan604 1y ago
  You're asking a question in response to a question. Your Type Ia link suggests this is not what is happening with Betelgeuse though. Its companion star is not a white dwarf. Betelgeuse itself is the start expected to go boom. So what happens to its companion? The anim you linked to shows that the white dwarf's explosion didn't destroy its larger star companion, but Betelgeuse is the opposite with the larger star going boom.
  - dontlikeyoueith 1y ago
    You're misunderstanding. I'm not saying Betelgeuse would be a type Ia. Betelgeuse will be a Type II supernova. I'm wondering whether Type II supernovae with smaller partners later become Type Ia once the larger partner explodes and becomes a white dwarf. The former smaller partner then becomes the relatively larger partner that loses mass to the remnant.
bongoman42 1y ago
For all we know, it might have gone supernova in the last few hundred years and we've yet to receive the light from it.
- dylan604 1y ago
  Betelgeuse is approximately 650 to 700 light-years away from Earth, so if you consider a few 300 then that means we have at least ~350 years to continue studying it.
- NooneAtAll3 1y ago
  in relativistic terms, anything that we don't observe and hasn't observed us is happening at the same time as we are so there's no point
  - the8472 1y ago
    You receive a message from an an alien civilization 1000ly away that they have started a deterministic process that will shoot a death ray at earth in 500 years. Should you act on the information that there's doom heading for earth right now or not?
    - 542354234235 1y ago
      Nothing can travel faster than light. If the Death ray travels at the speed of light, then the 1,000 years it takes the message to get to us, and the 1,000 years it takes the Death Ray to get to us are exactly the same, so cancel each other out. So it would still be 500 years between message and Death Ray. If someone dropped a ball from a tall building with a message that said “in 5 minutes, I am dropping a ball filled with explosives”, you would still have the same 5 minutes if the building was 5 stories tall or 200 stories. The message and the danger have to travel the same amount of spacetime to get to you.
      - the8472 1y ago
        > So it would still be 500 years between message and Death Ray. Yes of course, but you'd still act as if the death-ray is on its way, i.e. firing it already happened 500 years before you received the message. The systems may be causally separated but as long as each follows near-deterministic processes we can still calculate its state forward. In the case of betelgeuse we could hypothetically, if we had sufficiently accurate models, derive from observations that it'll explode in 100 years (relative to the observed state) which given the separation means the light of that event would only be 100ly away which in a sense does mean the event already happened. We can't be certain, perhaps a rogue black hole might swallow it in the meantime, but for casual conversation "predictable thing effectively already happened and its results are on the way" is good enough, and if one one had to worry about GRBs aimed at earth even prudent.

dontlikeyoueith 1y ago

Wouldn't all Type Ia supernova be examples of at least one possible end state of such an event? https://science.nasa.gov/resource/type-ia-supernova/ https://science.nasa.gov/resource/type-ia-supernova/ The larger star explodes first in a Type II supernova, becomes a Type Ia.

dylan604 1y ago
You're asking a question in response to a question. Your Type Ia link suggests this is not what is happening with Betelgeuse though. Its companion star is not a white dwarf. Betelgeuse itself is the start expected to go boom. So what happens to its companion? The anim you linked to shows that the white dwarf's explosion didn't destroy its larger star companion, but Betelgeuse is the opposite with the larger star going boom.
- dontlikeyoueith 1y ago
  You're misunderstanding. I'm not saying Betelgeuse would be a type Ia. Betelgeuse will be a Type II supernova. I'm wondering whether Type II supernovae with smaller partners later become Type Ia once the larger partner explodes and becomes a white dwarf. The former smaller partner then becomes the relatively larger partner that loses mass to the remnant.

bongoman42 1y ago

For all we know, it might have gone supernova in the last few hundred years and we've yet to receive the light from it.

dylan604 1y ago
Betelgeuse is approximately 650 to 700 light-years away from Earth, so if you consider a few 300 then that means we have at least ~350 years to continue studying it.
NooneAtAll3 1y ago
in relativistic terms, anything that we don't observe and hasn't observed us is happening at the same time as we are so there's no point
- the8472 1y ago
  You receive a message from an an alien civilization 1000ly away that they have started a deterministic process that will shoot a death ray at earth in 500 years. Should you act on the information that there's doom heading for earth right now or not?
  - 542354234235 1y ago
    Nothing can travel faster than light. If the Death ray travels at the speed of light, then the 1,000 years it takes the message to get to us, and the 1,000 years it takes the Death Ray to get to us are exactly the same, so cancel each other out. So it would still be 500 years between message and Death Ray. If someone dropped a ball from a tall building with a message that said “in 5 minutes, I am dropping a ball filled with explosives”, you would still have the same 5 minutes if the building was 5 stories tall or 200 stories. The message and the danger have to travel the same amount of spacetime to get to you.
    - the8472 1y ago
      > So it would still be 500 years between message and Death Ray. Yes of course, but you'd still act as if the death-ray is on its way, i.e. firing it already happened 500 years before you received the message. The systems may be causally separated but as long as each follows near-deterministic processes we can still calculate its state forward. In the case of betelgeuse we could hypothetically, if we had sufficiently accurate models, derive from observations that it'll explode in 100 years (relative to the observed state) which given the separation means the light of that event would only be 100ly away which in a sense does mean the event already happened. We can't be certain, perhaps a rogue black hole might swallow it in the meantime, but for casual conversation "predictable thing effectively already happened and its results are on the way" is good enough, and if one one had to worry about GRBs aimed at earth even prudent.