>Gemini North telescope in Hawai‘i reveals never-before-seen companion to Betelgeuse, solving millennia-old mystery
https://science.nasa.gov/resource/type-ia-supernova/
The larger star explodes first in a Type II supernova, becomes a Type Ia.
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.
so there's no point
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.
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.
We don’t know the Death Ray is on its way. Maybe a new alien was elected Supreme Gbectravic and canceled the project. We are guessing what will happen in 500 years, whether we are looking at our sun or a star 1,000 light years away.
And since light is the universal speed limit for all things, including information, then for casual conversation when we observe something is when it is effectively happening.
Perhaps a distinction is that we like to think that at least in principle we can influence almost any future events that are causally downstream of previous events on Earth. Even someone with very lethal radiation poisoning (alive but predictably dead) might just be one hypothetical stem cell transplant treatment away from defying the previous odds. So we don't treat those as set in stone.
Something causally separated on the other hand is seen as a mechanistic process. And there are very few things that would stop a star from becoming a supernova.
That reminds me of the short story Schwarzschild Defense https://archive.is/SZbHa#selection-1162.0-1162.1
>This discovery provides a clearer picture of this red supergiant’s life and future death. Betelgeuse and its companion star were likely born at the same time. However, the companion star will have a shortened lifespan as strong tidal forces will cause it to spiral into Betelgeuse and meet its demise, which scientists estimate will occur within the next 10,000 years.
It's unfortunate our flesh lasts but a blink of cosmic time. That would be something to witness.
My preferred solution to the Fermi paradox is that hundred million year long lifespans become trivial relatively soon at which point sublight speed galactic travel becomes no big deal and the differing time scale means that not being contacted by an alien intelligence simply hasn't happened yet, have you tried to establish communication with an ant hill in the last 10 seconds? Everybody else in the galaxy who could talk to us lives so long that they just haven't tried to say hello in the last 10,000 years because they were out to lunch.
edit: apparently, yep, that's why.
And from the original NOIRLab link: “This discovery answers the longstanding mystery of the star’s varying brightness”.
On the other hand, if the merger happens after the star has started burning carbon, it would have no effect. The explosions and collapses occurring in a supergiant are driven by successive phases of nuclear fusion in the core (collapse when one kind of fuel is exhausted, explosion as the previous fusion products become fusion ingredients), and they happen on a very short timescale (starting at thousands of years and ending at days before the star goes supernova). The presence of lighter elements billions of km away would not really have any impact on that.
The detection appears to be statistically very marginal, 1.5sigma, and the image contains a very similar bright spot on the opposite side of the star (which, for some reason, does not warrant a detection claim).
That collapse reduced the gravitational potential energy of the mass of that nebula, which through accelleration, friction, and pressure, was turned into heat energy.
That heated mass will emit black-body emissions, and so the gravitational energy is now being radiated as light.
One interesting thing is that this star was detected at visual wavelengths, not infrared. While not undergoing fusion, it’s hot enough to glow blue-white.
layer8•6mo ago