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NUCLEARSPACE MESSAGE BOARD (ACTIVE) -> OPEN FORUM -> MIRA STAR UNRAVELED
Post Info TOPIC: MIRA STAR UNRAVELED
NUKE ROCKY44


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MIRA STAR UNRAVELED
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Recently news reports of a star MIRA A is seen as coming apart. This is a binary system MIRA A + MIRA B. As seen by UV wavelength filter by the GALEX spacecraft. Does anyone know why this star might not have followed the path of other stars having exhausted easy light nuclei fuel at the left top of the 'valley of stability' late enough in stellar life not to have exploded as a supernova ?

Could this Star keep burning fuel up the other side of the nuclei 'valley' or is this too difficult for most stars to burn? 

Although this spacecraft scans in the UV wide angle mode for faint galaxies in UV wavelengths wonder if a spacecraft with less sensitivity could video the heat from NTR engines of a spacecraft traveling to Moon or Mars in real time?

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Bruce Behrhorst
10kBq Jaro


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NUKE ROCKY44 wrote:
Could this Star keep burning fuel up the other side of the nuclei 'valley' or is this too difficult for most stars to burn? 
Because fusion "burning" increases mass (fusing two lighter nuclei to make a heavier one), the process is always from left to right on the "valley of stability" diagram.
So going "up the other side" is an endothermic process: energy is absorbed, rather than liberated.
That's why supernovae happen: the core collapses under its own weight, since there is no more energy production to counter gravity.
In the process, the outer layers get heated by a rebounding shockwave, which instantly ignites the light elements that remained in the outer layers.
BOOOOOM !



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GoogleNaut


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Yep...

and interestingly enough, very high resolution computational hydrodynamic modelling suggests that this process is not as symmetric as once thought: turbulence in the hydrodynamic shockwave causes extensive fusion and stirring within the outer layers of the core--which produces far more heavy elements than once thought--and a greater fraction of them are ejected...

Supernovas end up producing quite a lot of heavy elements--and Supernova 1987A in the Large Magellanic Cloud is thought to have had a bright afterglow atleast in part powered by the decay of Nickel-56.






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