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Beating heart of a quantum time machine exposed

This super-accurate timekeeper is an optical atomic clock and its tick is governed by a single ion of the element strontium

Enigma Number 1734

Feedback: Ingredient-free aphrodisiac

See the light

Buzz off

Train brain drain

Environment

Netted Costa Rican birds pay small price for art

Enigma Number 1733

Feedback: Read this and you’re caught

Blind as a cat

That tingling feeling

Eco-friendly killing

Supernova-powered bow shock creates cosmic spectacle

Enigma Number 1732