infrared

A dog's world is not black-and-white, it is blue and yellow. Bees and many songbirds see ultraviolet patterns that are invisible to us. Pit vipers image heat. Mantis shrimp carry 12 to 16 photoreceptor types but use them in an unexpected way. Every animal lives inside a visual world shaped by which wavelengths mattered most to its ancestors.

In 1800, William Herschel used prisms and thermometers to discover infrared radiation, proving that visible light is just a tiny fraction of the spectrum. A revelatory experiment on the nature of light.

JWST sits 1.5 million kilometers from Earth, sees light from galaxies 280 million years after the Big Bang, and is actively rewriting cosmology. Here's how the most ambitious telescope ever built actually works, and what it has found through 2026.