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SCIENCE

The Claim

Red giants and red supergiants produce elements up to iron through nuclear fusion.

Verified by Lenz ·

The Short Version

The statement mixes two very different kinds of stars. Red supergiants can build up to iron in their cores through successive fusion stages, but ordinary red giants do not get that far and generally stop around carbon and oxygen. It also blurs the fact that much iron-peak material released into space is made during the supernova explosion, not just during the red-supergiant phase.

Caveats

  • "Red giants" is too broad: typical low-mass red giants do not fuse elements up to iron.
  • Building an iron core in a massive red supergiant is not the same as saying red giants in general produce iron.
  • A large share of iron-peak elements found in the universe comes from explosive supernova nucleosynthesis, not only from steady fusion before the explosion.

The Receipts

  1. What is Your Cosmic Connection to the Elements?

    NASA

  2. Stellar Evolution

    Chandra X-ray Observatory

  3. Stellar Evolution

    NASA

  4. Nucleosynthesis and Chemical Evolution of Galaxies – 1.3 Nucleosynthesis Beyond Helium

    NASA/IPAC Extragalactic Database (Level 5 Review)

  5. Supernova Nucleosynthesis in Massive Stars

    The Astrophysical Journal

  6. Lecture 18: Evolution of High Mass Stars

    University of Alberta

  7. Field Guide to X-ray Sources – Life Cycles of Stars

    Chandra X-ray Observatory (NASA/SAO)

  8. Cosmic Evolution - Stellar

    Harvard CfA

  9. Lecture 15: Red Giants

    The Ohio State University

  10. ASTRO 801: Massive Star Evolution and Supernovae

    Pennsylvania State University

+ 5 more sources — see the full list on Lenz

Filed Under

Nuclear FusionRed GiantsRed SupergiantsStellar Nucleosynthesis

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