Light

Light is a fundamental part of the Universe. The speed of light in a vacuum is the cosmic speed limit: no matter how advanced our technology, we'll never travel faster than that. Since the speed of light is a natural measurement, we often measure distances in space in lightyears. The Sun's light is the ultimate source of all energy for life on Earth: without the warmth and energy from sunlight, not even plant life could exist.

Why the sky is dark at night © Getty Images

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Light

Olbers’ Paradox Why the sky is dark at night

Blue light from smartphones may lead to brain damage… in flies

Light shed on secrets of glow-in-the-dark sharks

Can taking digital photos damage art?

Why does light leave the position from which it is created?

Do two mirrors facing each other produce infinite reflections?

Can weather forecasters predict rainbows?

Is the dark really making me sad?

Why is red light used on submarines?

How does ‘glow in the dark’ work?

What is the darkest human-made substance?

The cool gadgets list – April 2017

The cool gadgets list – February 2017

Dream TVs from CES 2017

Does the speed of light ever change?

Light

Olbers’ Paradox | Why the sky is dark at night

Olbers’ Paradox Why the sky is dark at night