Threshold 3 · New chemical elements

Chemicals Cook Up

Stars forge carbon, oxygen and iron in their cores and scatter them when they die; the periodic table fills in.

13.5 billion years ago From the first supernovae onward 2 of 7 lessons ready
JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC Threshold 1: The Beginning, 1 January, 00:00:00 1 Threshold 2: Formation of Stars, 5 January 2 Threshold 3: Chemicals Cook Up, 8 January 3 Threshold 4: The Early Earth, 2 September 4 Threshold 5: Emergence of Life, 30 September 5 Threshold 6: Collective Learning, 31 December, 23:48:33 6 Threshold 7: The Agricultural Revolution, 31 December, 23:59:32 7 Threshold 8: Modernity Strikes, 31 December, 23:59:59 8 Threshold 3 8 January
On the cosmic calendar this threshold begins on 8 January.

The early universe made only hydrogen, helium and a trace of lithium. Everything else, the carbon in your cells, the oxygen you breathe, the iron in your blood, the gold in a ring, was made later, inside stars and in the violent events that end them.

This chapter follows the elements from their forges to the places they were scattered. It reads the periodic table as a history book, asks why carbon in particular is the element of complexity, and follows the new molecules out into the cold clouds between the stars where the ingredients of planets and life collect.

By the end, the universe has a chemistry, and chemistry is what the rest of the story is made of.

Lessons

  1. 3.1
    Where the elements come from

    Stellar nucleosynthesis: how stars build carbon, oxygen and iron.

    Draft
  2. 3.2
    Making gold

    Supernovae and neutron-star mergers, the violent events that make the heaviest elements.

    Planned
  3. 3.3
    The periodic table as a history book

    Every element has an origin story; the periodic table arranged by where each one was made.

    Planned
  4. 3.4
    Why carbon?

    Bonding, chains and rings: why carbon chemistry is the chemistry of complexity.

    Planned
  5. 3.5
    Molecules in space

    Dust, ice and organic molecules between the stars.

    Planned
  6. 3.6
    From quarks to the Higgs

    The fundamental particles and the four forces that shape matter.

    Draft
  7. 3.7
    Are you really made of stardust?

    The famous claim, tested element by element.

    Planned

Disciplines