3 ms·
Nobody knows, of course. But heavier elements do get pushed up to a stars surface so they look more prevalent. This is clearly the sort of oddity stuff science
by ianai 4y ago
Nobody knows, of course. But heavier elements do get pushed up to a stars surface so they look more prevalent.
This is clearly the sort of oddity stuff science and society should inspect with gusto. There’s surely much to learn there. I wonder whether JWST has time allocated for it?
Also at 356 ly away this is basically a neighbor. That could be very telling in itself. Should be easier to study too.
- perihelions 4y ago- "But heavier elements do get pushed up to a stars surface" That doesn't help here, because these aren't elements that a stellar core can create in the first place. https://en.wikipedia.org/wiki/Nucleosynthesis https://en.wikipedia.org/wiki/Nucleosynthesis
- PaulHoule 4y agoMy understanding is that the origin of heavy elements in the Earth is not well understood. Ordinary supernovae don’t seem to produce enough, it is currently thought that they might come from neutron star collisions (a.k.a. “Kilonova”) but maybe stars like that star produce a lot.
- adrian_b 4y agoThe kinds of nuclear reactions that can produce heavy elements are reasonably well understood, because they depend on energetic constraints. Most chemical elements heavier than germanium need neutron fluxes of various intensities for their production, while a few isotopes need high-intensity proton fluxes. What is less well understood is which are the astronomical objects where the conditions for such reactions happen, e.g. a high-intensity neutron flux of an appropriate intensity and neutron energy. In any case, no known phenomenon could produce such a neutron flux in steady-state conditions, for a long time, so all candidates are explosion-like phenomena, e.g. when a star explodes becoming a supernova or a nova, or when two neutron stars collide. That is why if trans-plutonium elements would be produced in such a star that does not appear to explode, this would need a completely new explanation.
- adrian_b 4y agoWhile the elements between strontium and uranium could not have been normally created in a stellar core, their presence is still not completely unusual, because most younger stars, including our Sun, have been formed from material that had been previously produced by supernova explosions, where the high neutron flux can produce such elements in great abundance. What would be really strange is if the attribution to elements heavier than plutonium of some of the peculiar spectra observed there is correct. While plutonium is the heaviest long lived element, with a lifetime of up to 100 million years, all heavier elements have a very short lifetime, so they should have already decayed since the supernova explosion that could have produced them. However the spectra identification for transitions that cannot be reproduced in a laboratory are extremely uncertain, because there exists no method to compute them with high precision for elements with so many electrons. So it is still possible that whatever has been identified tentatively as e.g. californium, might be just a much more common element that is present as a ion that has lost a large number of electrons and which is also in an extremely high magnetic field, so its spectrum might be very unlikely those that are produced in normal experimental conditions. This will not be completely new for astronomy. At some point it was believed that there are 2 new chemical elements discovered in stars due to their unusual spectra, which were named coronium and nebulium. Later it was discovered that they are just iron and oxygen whose spectra have been modified because their ions have lost more electrons than it can happen in normal terrestrial experiments.
- wruza 4y agoThat’s what I was thinking about, very interesting info, thanks!