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Ac: 2·8·18·32·18·9·2

elements · 89 / 118 · All 118

Ac

Actinium

Z 
89
Mass 
227
Lifeforce 
Earth
A small sealed glass vial on a dark shelf, giving off a faint blue light.
Plate · Actinium Actinium glows from within, a quiet blue that does not shy away from the dark.

Stable earth: holds form, endures, builds the structures on which all else stands. The slow time of matter, the patience of mountains.

Born in supernova explosions, the death of massive stars scattering their innards across the galaxy.

Family portrait: this element's own portrait is not written yet. Mendeleev left gaps; we label ours.

Tool · Cosmic origin

Where your atoms come from

Ac · Supernova

Born in supernova explosions, the death of massive stars scattering their innards across the galaxy.

65 of the 118 elements share this origin.

Choose a stage: click, or arrow keys. · Cosmic nucleosynthesis · current standard model

Tool · Periodic table

Your place in the system

  • Fire
  • Water
  • Air
  • Earth
  • Source

Click any element to go there.