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'They want to turn off the Sun': UK’s £50M bet could rewrite Earth’s atmosphere forever

Produced by: Mohsin Shaikh

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Firefly A rare Earth-like planet in the habitable zone of a sun-like star, covered in lush greenery

Sun Shield

The UK is funding £50M in real-world experiments to reflect sunlight and cool the Earth—marking its first foray into climate geoengineering.

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Bright Skies

Scientists will trial Marine Cloud Brightening—spraying sea salt into clouds to make them whiter and more reflective.

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Sky Injections

Stratospheric Aerosol Injection involves releasing particles high in the sky to bounce sunlight back into space and reduce heat.

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Real Data

Aria’s lead says simulations aren’t enough—small outdoor trials are essential to understanding these theories in practice.

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Nature’s Clues

Volcanic eruptions and ship trails have already shown how atmospheric particles can brighten clouds and cool the planet.

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Pollution Paradox

Emissions from ships create reflective cloud streaks—proof that even unintentional pollution can cool the Earth.

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Heat Blanket

Another method being studied involves thinning cirrus clouds—those wispy heat-trapping clouds—to let more warmth escape into space.

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Flight Effect

Planes may cool Earth by tweaking clouds; sulphur from fuel modifies cloud behavior, showing unintentional geoengineering in action.

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Cool Controversy

Critics warn that geoengineering could trigger unknown side effects—and may distract from cutting carbon emissions urgently needed now.