How Do Vaccines Work?
A vaccine shows your immune system a harmless preview of a pathogen so it can build a memory of it in advance. The training is real; only the threat is fake.
Science
The physics, chemistry and biology behind ordinary things, in plain language, with the settled parts stated plainly and the open questions marked as open.
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Why Is Nuclear Fusion Always 30 Years Away?
The joke is old and the reason is specific: fusion needs conditions that only exist inside stars, and building them on Earth costs more energy than the reaction has so far returned.
Why Is the Sky Blue?
Sunlight contains every colour. Air scatters the short blue wavelengths far more strongly than the long red ones, so blue arrives at your eyes from every direction at once.
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