← Back to course
Science Launch G4 / Week 07 / Monday
1/6
Week 07 · How We See

Monday

Seeing in the dark
// Light bounces into our eyes
⏱ about 15 min

Monday: Seeing in the dark

Rocket digs through the hall closet with the door shut. "I know my red sneaker is in here somewhere," he mutters.

He pats coats and boxes. He cannot see a thing.

Raven opens the door. Light spills in, and there is the sneaker, right by his knee.

"It was there the whole time," Rocket says. "My eyes were open. So why couldn't I see it?"

"What do you notice changed when I opened the door?" Raven asks.

Nova glows softly in the doorway. "Here is a clue," she says. "Your eyes catch something. They do not send anything out."

Light has to reach your eyes

You see an object when light bounces off it and enters your eyes.

To bounce off a surface is to reflect. Most things you see are reflecting light.

A light source gives off its own light. The Sun, a lamp and a flashlight are light sources.

The Moon is not a light source. Moonlight is really sunlight reflecting off the Moon.

In a dark closet, no light reaches the sneaker. So no light can bounce from it into your eyes.

ThingIs it a light source?
The Sun?
The Moon?
A lit flashlight?
A red sneaker?
A mirror?
WHY THIS EXERCISELight sources make light. Everything else is seen because it reflects light.
WHY CAN WE SEE?
  • Read the question.
  • Tap your answer.
Why could Rocket see the sneaker after Raven opened the door?
To bounce off a surface is to ____.
WHY THIS EXERCISEReflected light is how we see almost everything around us.

Makers and bouncers

Every object you see is either making light or bouncing light.

A lamp makes light. A book on the table only bounces the lamp's light.

Turn the lamp off at night, and the book seems to vanish. It is still there.

No light is reflecting from it into your eyes.

LIGHT SOURCE OR REFLECTOR?
  • Read the question.
  • Tap your answer.
Why does the Moon look bright at night?
Which one is a light source?
You open your eyes in a dark closet. Why can you not see?
HOW ROCKET FINALLY SAW HIS SNEAKER
  • ?The light enters Rocket's eyes.
  • ?Raven opens the closet door.
  • ?The light hits the sneaker.
  • ?Light reflects off the sneaker.
  • ?Light from the hall shines in.
WHY THIS EXERCISESeeing needs light to reach an object and reflect into your eyes.
Something that gives off its own light is a light ____.
Moonlight is really ____ reflecting off the Moon.
Try it
With a grown-up, go into a room and turn off the lights.
Wait a moment. What can you still see? Where is that light coming from?
Turn the lights back on and notice the change.

Great start! Tomorrow we learn how light travels from a source to your eyes.