elements · 92 / 118 · All 118

Uranium

Z: 92
Mass: 238.029
Lifeforce: Earth

Sun-power in the reactor, annihilation in the bomb: the same atom. Uranium carries light and shadow undivided: the pendulum at its outermost point, Pendelmodus written into matter itself.

A terraced slope with laid stone foundations and visible roots; a figure sets a stone in place. — Plate · Earth Earth never hurries. It *holds*, stone by stone, whatever is meant to last.

Forged in neutron-star collisions. The heaviest element found in significant quantities on Earth, and the engine of every nuclear reactor.

Lab note · The heaviest element found on Earth in appreciable quantities; forged in neutron-star collisions.

Tool · Cosmic origin

Where your atoms come from

U · Neutron stars

Forged in the collision of neutron stars, among the rarest events in the cosmos. Older than the Sun.

8 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

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