elements · 34 / 118 · All 118

Selenium

Z: 34
Mass: 78.971
Lifeforce: Water
In the body: brain, thyroid, liver

Roughly fifteen milligrams in the whole body, barely enough to weigh. And without that trace the antioxidant defence never starts: selenium is its cofactor.

An old handheld light meter is held toward the sky, its needle settling. — Plate · Selenium Selenium drinks the light and serves *quietly*, wholly intent on keeping other things safe.

Receptive water: receives, completes, draws toward wholeness. Hungers for what makes it whole. Bound, becomes the conductor of life's processes.

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.

Lab note · In the body ≈15 mg; cofactor of the antioxidant defence.

Tool · Cosmic origin

Where your atoms come from

Se · 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

H He Li Be B C N O F Ne Na Mg Al Si P S Cl Ar K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe Cs Ba La Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn Fr Ra Ac Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No Lr Rf Db Sg Bh Hs Mt Ds Rg Cn Nh Fl Mc Lv Ts Og

Fire
Water
Air
Earth
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