Neutron star found *inside* a red giant.

Neil Newell
Neil Newell
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Topic 197332

Nature is reporting an announcement from the American Astronomical Society that astronomers using the Magellan telescope have found a neutron star *inside* another star (a red giant).

I've never heard of them, but apparently 'Thorne-Zytkow' objects were first proposed in 1975 (by Kip Thorne and Anna Zytkow, hence the name) and this object presents "the most compelling observational evidence" to date.

Be interesting to see how it evolves over time (if anyone has a billion years or so to spare).

astro-marwil
astro-marwil
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Neutron star found *inside* a red giant.

Hallo Neil Newell!
It would be interesting to know, how this was detected.
If this is real, it must be a very hot candidate for the next supernova relative close by (about 200K LY), as there must be very high friction and mass accretion by the neutron star inside the sphere of the red giant. There must be two scenarios for the supernova:
1) The neutron star has accreted fist sufficient mass to explode before he spirals into the center of the red giant, or
2) the neutron star will become slowed down so quick that he will fall into the center of the red giant and explode there, just shortly before fully combined with it.

Kind regards and happy crunching.
Martin

Neil Newell
Neil Newell
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If I understand it correctly,

If I understand it correctly, they detected it from its spectral signature - because it has to burn "through unusual nuclear fusion pathways" it's enriched in lithium, rubidium and molybdenum.

I did wonder too about it going supernova - and how it might relate to X-ray bursters (where a neutron star in a binary system accumulates material from its companion until there's a thermonuclear explosion). I bet it's got the astrophyicists thinking, anyway!

Mike Hewson
Mike Hewson
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I visualise this as the

I visualise this as the smaller star within acting like a spoon stirring the pot. So the neutron star itself won't be doing much fusing per se, but it's gravitational effect upon the core of the red giant will be causing tides and hence mixing amongst inner core layers. That would not normally happen in a red giant left alone to evolve.

Cheers, Mike.

I have made this letter longer than usual because I lack the time to make it shorter. Blaise Pascal

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