The Rest Is Science The Rest Is Science

Why Is It A Colour Wheel & Not A Line?

Aug 5, 2026 · 47m

Summary

Michael Stevens shares his obsession with organizing 152 Crayola crayons, exploring color theory, the psychological nature of purple, and why cameras fail to capture fluorescent hues. Hannah Fry then answers listener questions, explaining the fluid dynamics behind the tea leaf paradox, how firefighters use surfactants to create "wetter" water, and the cybersecurity challenges of communicating with space probes.

Topics discussed

Introduction and Michael's crayon obsession Ad: Tremfya for Crohn's disease Ad: Carvana car selling service The physics of color: Spectrums, wheels, and magenta Fluorescent crayons and camera sensor limitations Color theory in makeup and skin tone correction Ads: Sally education platform and Toyota Listener Q&A: The tea leaf paradox and fluid dynamics Listener Q&A: Can water be 'wetter'? Surface tension Listener Q&A: Hacking space probes and closing thoughts
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