![]() Some 7Li is also made in the Big Bang and a small fraction by cosmic ray fission. But most of the far more common 7Li isotope is without question made in low-mass stars and spewed out out into the Universe as the star dies. 6Li is indeed made by cosmic rays (fast-moving nuclei) hitting other nuclei and breaking them apart. The iron that massive stars make right before they explode as supernova is all destroyed/collapsed in the remnant. Basically all the iron in the Universe is made in explosive nucleosynthesis. I don’t agree that Cr and Mn are made only in “Large Stars”, but Fe is made in both “Large Stars” and “Supernovae”. There should be a lot of orange in the bottom half of the diagram. Dying low-mass stars (aka “Small Stars”) make substantial amounts of the heavy elements, including most of the Pb in the solar system.These categories are therefore 1) confusing and 2) incorrect no matter how you slice it. In this case, “Large Stars” could mean that massive stars make it before they explode and the supernovae is just the mechanism for kicking out. It would also be possible to think that “Supernovae” refers to both massive star core-collapse supernovae and exploding white dwarfs. I will assume that “Large Stars” refers to the production in high-mass stars both during their lives and during the explosion that spews products of their nuclear fusion into the interstellar gas. The interpretation that makes the graphic the least wrong is the “supernova” here means “Type Ia Supernovae” or “exploding white dwarfs” as I call them. Which “supernova” is being referred to in the Wikipedia graphic is not clear. But sometimes white dwarfs that are in binary systems with another star get enough mass from the companion to become unstable and explode as so-called Type-Ia supernovae. Low-mass stars usually end their lives as white dwarfs. High-mass stars end their lives ( at least some of the time) as core-collapse supernovae.Note that the original source cited by the Wikipedia article just has the chart, with no additional information or links that I can find. In its death throes, a low-mass star can have a much larger radius than a normal high-mass star. As this wonderful graphic from NASA’s Chandra website shows, all stars at the end of their lives swell up to red giant and supergiant stars. It does not make sense to think of nucleosynthesis origin having to do with the radius of the stars. I will assume that “Large Stars” and “Small Stars” are “High-Mass Stars” and “Low-Mass Stars”, respectively.The underlined phrases below represent possible topics for future blog posts where I (or colleagues I coerce bribe ask) can go into more in more detail later, including why we think we are on the right track. I am trying to avoid going into all details in this single blog post. In many cases, the Wikipedia graphic is presenting information that is flat-out wrong. Here is a discussion of the some of the differences between the Wikipedia version and mine. The former figure on Wikipedia was based on this plot from Northern Arizona Meteorite Laboratory Why does your version have different information than the well-known Wikipedia entry? However, the main point of this blog post is to present the chart and address the following question: There will be additional versions showing what this plot would look like if you were in the early Universe, or if you consider the origin of the elements on the Earth, etc. In an upcoming blog post, I will give details on my sources and assumptions for interested parties. This graphic draws on an enormous amount of labor from astronomers and physicists. I also updated the sources of the heavy elements to reflect the current semi-consensus. I have ignored the elements beyond U in this plot, but not including Tc and Pm looked weird, so I have included them in grey.įor this version, I tried to avoid the technical terms and jargon used in the original plot. Tc, Pm, and the elements beyond U do not have long-lived or stable isotopes. Elements with more than one source have the approximate amount due to each process indicated by the amount of area. My current version of the periodic table, color-coded by the source of the element in the solar system.
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