What is Radiation pressure?

Radiation pressure is when light pushes on things, just like wind pushes on your face.

Imagine you're outside on a breezy day, and you feel the wind gently pushing against your skin. Now imagine that instead of wind, it’s light coming from the sun. Even though we can’t feel light like we feel wind, it still has enough strength to push, very, very slightly, on things like tiny particles or even spaceships.

Like a whispery push

Think of radiation pressure as a whispery push that only really matters when you're super small or super far away. For example, tiny dust grains floating in space get pushed around by sunlight, which helps them move through the solar system. It’s like how a little breeze can move leaves on a tree, just much, much smaller.

A spaceship’s friend

Sometimes, scientists use radiation pressure to help spaceships move without using fuel. It's not strong enough to make a big difference for something as heavy as a car or a person, but it helps tiny spacecraft travel farther and farther through space, like getting a little extra nudge from the sun every now and then! Radiation pressure is when light pushes on things, just like wind pushes on your face.

Imagine you're outside on a breezy day, and you feel the wind gently pushing against your skin. Now imagine that instead of wind, it’s light coming from the sun. Even though we can’t feel light like we feel wind, it still has enough strength to push, very, very slightly, on things like tiny particles or even spaceships.

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Examples

  1. A solar sail uses radiation pressure from the sun to push a spacecraft through space.
  2. Light hitting tiny dust particles in space can gently nudge them around.
  3. Imagine being pushed by a stream of invisible, tiny balls, that's how radiation pressure works.

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