Key Idea.
Section 1
Distance Changes Brightness
Have you ever noticed that a flashlight looks blindingly bright up close but dim from far away? This rule applies to stars, too.
A star's apparent brightness is a measure of how bright it looks from Earth. This brightness is determined by the star's distance. A star that is close will appear intense and bright, while a star that is far away will appear faint and dim.
Section 2
The Sun's Overwhelming Light
Because the Sun is the closest star, its apparent brightness is incredibly powerful. When the Sun is in the sky, it pumps a massive amount of light toward Earth.
This light is so intense that it lights up the entire world. While other stars might actually be bigger or hotter than the Sun, their great distance makes them look like weak, flickering candles compared to the Sun's blazing fire.
Section 3
Where Do the Stars Go?
When the Sun rises, the stars do not leave. They are still in the sky, but they become hidden.
The Sun's light is so strong that it overwhelms the faint light from distant stars. Imagine holding a candle next to a giant spotlight; you wouldn't see the candle's flame. Similarly, the Sun's brightness makes the distant stars impossible to see until the Sun sets.
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Section 1
Distance Changes Brightness
Have you ever noticed that a flashlight looks blindingly bright up close but dim from far away? This rule applies to stars, too.
A star's apparent brightness is a measure of how bright it looks from Earth. This brightness is determined by the star's distance. A star that is close will appear intense and bright, while a star that is far away will appear faint and dim.
Section 2
The Sun's Overwhelming Light
Because the Sun is the closest star, its apparent brightness is incredibly powerful. When the Sun is in the sky, it pumps a massive amount of light toward Earth.
This light is so intense that it lights up the entire world. While other stars might actually be bigger or hotter than the Sun, their great distance makes them look like weak, flickering candles compared to the Sun's blazing fire.
Section 3
Where Do the Stars Go?
When the Sun rises, the stars do not leave. They are still in the sky, but they become hidden.
The Sun's light is so strong that it overwhelms the faint light from distant stars. Imagine holding a candle next to a giant spotlight; you wouldn't see the candle's flame. Similarly, the Sun's brightness makes the distant stars impossible to see until the Sun sets.
Book overview
Jump across lessons in the current chapter without opening the full course modal.
Continue this chapter