Why the vast expanse of the universe appears dark

Space · Published 29 October 2026 Swipe more like this →

In short: Space is often described as a void, but why doesn't it glow? This video explores the fundamental reasons behind the darkness of the cosmos and the physics of light in a vacuum.

The video examines the visual nature of space, addressing why the universe lacks a pervasive glow despite containing countless stars and galaxies. It provides context on how light travels through the vacuum and the conditions that allow the background of the universe to appear black to our eyes.

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