
NASA Team Probes Peculiar Age-Defying Star - kartikkumar
https://www.nasa.gov/feature/goddard/2016/nasa-team-probes-peculiar-age-defying-star
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terravion
It is incredible how much we know about objects mind bogglingly far away and
also how much we don't know and have yet to discover.

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palakchokshi
Just a theory but what do we know of dying stars getting a new breath of life
due to nearby supernovae? Seems like the star died and material from nearby
supernova seems to have drifted into it's neighborhood and jump started the
star.

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S_Daedalus
I can't imagine that the concentration of matter ejected, which diffuses
impressively, would have been so concentrated so far away. Supernovae
shockwaves are thought to be a candidate for touching of the process of dust
cloud collapse and stellar formation, but an old star is usually a really
dense core and a very wispy atmosphere, relatively speaking.

Maybe a shockwave could set off a nova event, or the addition of matter could
trigger a collapse, but I'm not sure how it could jumpstart nuclear fusion
again.

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pixl97
Do we have any idea what occurs if a young star and an old star merge? Of
course my first thought on that line of thinking is that would cause some type
of explosion or ejecta that would be noticeable, but maybe not.

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S_Daedalus
I think that might be one of those seemingly straightforward questions that's
actually very nuanced, because I suspect that the combined masses of the two
stars will have a lot to say about the outcome. For a couple of Solar mass
stars, I would expect... a big explosion. I can't imagine it really happening
though, except in a one-in-a-<insert -illion of choice> "head-on" collision.
In that case, whether it blew apart and re-settled into a star, or a nebula,
or... just blew apart, would be a function of mass and momentum.

In the case of slowly decaying orbits, one star usually ends up stripping most
of the atmosphere from its partner, before the core eventually passes its
Roche limit, breaks apart, and is accreted. In that case you get a series of
Novas (not to be confused with supernovas), and a somewhat larger star when
all is finally said and done. Lots of debris, occasionally very bright.

It's hard to imagine a situation in which two stars "merge" without a slow
process of cannibalization. Compact collapsed bodies like white dwarves,
neutron stars and the rest definitely do merge, but they're _so_ much denser
than a "living" star.

