A DIY experiment demonstrates how to visually observe individual atoms undergoing nuclear decay. Using americium-241 from a smoke detector as an alpha particle source, the setup employs a zinc sulfide-coated scintillation screen to convert radioactive emissions into visible light. The experiment reveals thousands of momentary flashes when alpha particles strike the screen, creating what appears to be a "sea of sparks" - each flash representing energy released by a single atom's decay.

The setup requires careful preparation: complete darkness for 20 minutes allows eyes to adapt, while positioning the 37 kBq source within millimeters of the coated screen ensures visibility. A magnifying glass helps direct the faint light into the viewer's pupil, as each alpha particle produces only a few thousand photons. The experiment works because alpha particles, ejected with about a picojoule of kinetic energy, carry enough energy to create visible flashes when they interact with the zinc sulfide coating.

For those interested in trying this themselves, pre-assembled spinthariscopes are available for around $60, eliminating the need to handle radioactive materials directly. The experiment demonstrates that while individual atoms remain far too small to see directly, their nuclear transformations produce observable effects. This hands-on approach to visualizing radioactivity offers an accessible way to witness atomic-scale phenomena that would otherwise remain invisible to human perception.