Redshift: Why Distant Galaxies Glow Red

Hinzugefügt: 2026-05-25

[00:00:00]Why do JWST's earliest galaxies all look red?

[00:00:05]Their light is stretched by cosmological redshift. As space itself expands, photon wavelengths elongate, shifting ultraviolet and visible starlight into the infrared bands JWST is tuned to detect.

[00:00:19]Those little red dots are not actually red galaxies. They're ancient ultraviolet star factories seen through 13 billion years of cosmic expansion with their spectra tagged deep into the infrared.