Actinide
15 elements
Uranium
The heaviest naturally abundant element. Named after the planet Uranus. Enriched...
Plutonium
Named after the dwarf planet Pluto, following the uranium-neptunium-plutonium se...
Actinium
Glows an eerie pale blue in the dark as its radiation excites the surrounding ai...
Thorium
Named after Thor, the Norse god of thunder. Thorium oxide glowed white in gas la...
Protactinium
The name means parent of actinium, which it becomes through radioactive decay. O...
Neptunium
The first element beyond uranium ever created, named for the next planet out, fo...
Americium
Sits in nearly every home, invisibly: a speck of americium-241 in a smoke detect...
Curium
Named for Pierre and Marie Curie, honoring the study of radioactivity. So intens...
Berkelium
Named for Berkeley, California, home of the cyclotron that made it. Produced by ...
Californium
Named for California and the university that created it. One of the few elements...
Einsteinium
Discovered in the radioactive debris of the first hydrogen bomb test and named a...
Fermium
Also born in the Ivy Mike hydrogen bomb fireball of 1952, and named after Enrico...
Mendelevium
Named after Dmitri Mendeleev, creator of the periodic table, which predicted ele...
Nobelium
Named after Alfred Nobel, but the credit fight was messy: teams in Stockholm, Du...
Lawrencium
Named after Ernest Lawrence, inventor of the cyclotron, and the last of the acti...