Star Brightness and Size

4th Gradeβ€’35 minutesβ€’NGSS 4-ESS3-1

Learning Objective

I can compare the brightness and size of different stars.

Key Concepts

Stars create energy in their core through a process called nuclear fusion, where hydrogen molecules smash together to create helium.

Luminosity is a star's true brightness, measuring how much energy it shines from its surface, while apparent brightness is how bright a star appears from Earth.

A star's apparent brightness depends on its distance from Earth, not just its size or power, because closer stars appear brighter.

Practice Questions

This lesson includes 5 practice questions to reinforce learning.

View questions preview

1. What process creates the light and heat that stars emit?

2. Which of the following describes luminosity?

3. Explain why a smaller star can sometimes have more power (luminosity) than a bigger star.

...and 2 more questions

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