Physics · Radioactivity
Build a Nucleus
Explore how forces change the motion of objects. Choose a mode to begin.
Choose what to explore
Start with a mode
Each mode focuses on a different relationship between force and motion.
See what happens
Learning scene
Change a control and observe the model.
Chart Intro
Element
No nucleus
Add protons and neutrons to begin.
Empty
This nuclide does not exist.
Partial chart of nuclides
Protons (Z, up) vs neutrons (N, across)
Zoomed neighbourhood
Nearby nuclides
Full chart of nuclides
Z 0–94, N 0–146
Mass number
A = 0
Chart legend
Dark blue = stable · green = alpha · cyan = beta-minus · light blue = beta-plus · pink = proton emission · magenta = neutron emission · white = unknown
Choose a simulation mode to begin.