Learn on PengiAmplify Science (California) Grade 5Chapter 1: Why don’t we see a lot of stars in the daytime?

Session 3: Why Stars "Disappear" in the Day

Key Idea.

Section 1

The Atmosphere Acts Like a Curtain

Key Idea

The Sun is the closest star, giving it enormous apparent brightness. But why does the whole sky turn blue?

When sunlight hits Earth's atmosphere (the layer of air around our planet), the light scatters in all directions. This scattering creates a bright blue blanket over the sky. This blue glow is brighter than the stars behind it.

Section 2

The Daytime Sky Illusion

Key Idea

This process is called daytime sky illumination. The atmosphere lights up so much that it acts like a privacy curtain.

Behind this blue curtain, the stars are still shining. However, the scattered sunlight completely washes out their faint light. We cannot see the stars through the bright glare of the day.

Section 3

Restoring the View

Key Idea

The only reason we see stars at night is that the Sun sets. When the Sun goes down, it stops illuminating the atmosphere above us.

Without the bright blue glare to block the view, the faint light from distant stars can finally reach our eyes. The stars didn't appear; the "curtain" of sunlight was simply pulled back.

Lesson overview

Expand to review the lesson summary and core properties.

Expand

Section 1

The Atmosphere Acts Like a Curtain

Key Idea

The Sun is the closest star, giving it enormous apparent brightness. But why does the whole sky turn blue?

Section 2

The Daytime Sky Illusion

Key Idea

This process is called daytime sky illumination. The atmosphere lights up so much that it acts like a privacy curtain.

Behind this blue curtain, the stars are still shining. However, the scattered sunlight completely washes out their faint light. We cannot see the stars through the bright glare of the day.

Section 3

Restoring the View

Key Idea

The only reason we see stars at night is that the Sun sets. When the Sun goes down, it stops illuminating the atmosphere above us.

Without the bright blue glare to block the view, the faint light from distant stars can finally reach our eyes. The stars didn't appear; the "curtain" of sunlight was simply pulled back.

Overview

Lesson overview

Review the lesson summary and core properties without leaving the current page.

Overview

Section 1

The Atmosphere Acts Like a Curtain

Key Idea

The Sun is the closest star, giving it enormous apparent brightness. But why does the whole sky turn blue?

Section 2

The Daytime Sky Illusion

Key Idea

This process is called daytime sky illumination. The atmosphere lights up so much that it acts like a privacy curtain.

Behind this blue curtain, the stars are still shining. However, the scattered sunlight completely washes out their faint light. We cannot see the stars through the bright glare of the day.

Section 3

Restoring the View

Key Idea

The only reason we see stars at night is that the Sun sets. When the Sun goes down, it stops illuminating the atmosphere above us.

Without the bright blue glare to block the view, the faint light from distant stars can finally reach our eyes. The stars didn't appear; the "curtain" of sunlight was simply pulled back.