Astronomy
The Lyman-Continuum Emission from Star-Forming Galaxies
Quick fact
Lyman-continuum photons have wavelengths shorter than 91.2 nanometers—so energetic they can ionize hydrogen. These photons are produced by the hottest, most massive stars, which live only a few million years, and they are thought to have reionized the universe within the first billion years after the Big Bang.
Why this is interesting
You've seen pictures of glowing galaxies, but did you know some of their light is so energetic it can strip electrons from atoms? This extreme ultraviolet light, called Lyman-continuum emission, may hold the key to how the universe became transparent.