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Astronomers Find Star-Within-a-Star, 40 Years After First Theorized
derekmead writes: After 40 years, astronomers have likely found a rather strange celestial body known as a Thorne–Zytkow object (TZO), in which a neutron star is absorbed by a red supergiant. Originally predicted in the 1970s, the first non-theoretical TZO was found earlier this year, based on calculations presented in a paper forthcoming in MNRAS.
TZOs were predicted by astronomer Kip Thorne and Anna Zytkow, who wasthen postdoctoral fellow at CalTech. The pair imagined what might happen if a neutron star in a binary system merged with its partner red supergiant. This wouldn't be like two average stars merging. Neutron stars are the ancient remnants of stars that grew too big and exploded. Their cores remain small — about 12.5 miles across — as they shed material out into space. Red supergiants are the largest stars in the galaxy, with radii up to 800 times that of our sun, but they aren't dense.
TZOs were predicted by astronomer Kip Thorne and Anna Zytkow, who wasthen postdoctoral fellow at CalTech. The pair imagined what might happen if a neutron star in a binary system merged with its partner red supergiant. This wouldn't be like two average stars merging. Neutron stars are the ancient remnants of stars that grew too big and exploded. Their cores remain small — about 12.5 miles across — as they shed material out into space. Red supergiants are the largest stars in the galaxy, with radii up to 800 times that of our sun, but they aren't dense.
- Is the research reliable?
Well, the Monthly Notices of the Royal Astronomy Society is one of the longest running astronomy journals in the world, and, to my knowledge, has never done anything substantial to impugn its reputation. It also has a comparatively large impact factor. All signs that the peer review is considered of good quality.
- How can such a thing be stable? Is there any particular process that keeps one star inside the other?
Why wouldn't it be stable? More gravity means more fusion, not less.
The theory says it's a companion star that goes nova, and then is gradually de-orbitted into the larger gas giant.
- What even /is/ such a body? If you were to travel from the outside to the midpoint of the body, would you encounter two barriers of destructing heat, with some emptiness (I'd like to say "vacuum" but of course space is not exactly a vacuum) in between?
Or is it actually just something entirely unlike what you would imagine when someone says "star within a star"?
Oh, and just now I realize you hadn't read the summary. It's a neutron star inside a star. A neutron star is essentially a block of neutronium(essentially a gigantic neutron only nucleus) with some attached hanger on high energy plasma around.
It lasts for several hundred thousand years but the red giant is eventually absorbed into the neutron star which becomes a slightly larger neutron star or possibly a black hole.
So the red giant is just a big meal that takes a while to eat. But if you look around enough, you can find one in the middle of its course.
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