Earth & Space Science
You get to learn about the different types of stars, including their life cycles and their structure. Travel on a deep space mission to probe the galaxy for stars that contain habitable planets, and to learn about how black holes form from collapsed suns.
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After completing this tutorial, you will be able to complete the following:
What is a star, and how many are there in our galaxy?
~ A star is an extremely hot gas sphere that emits radiation, including visible light. There are billions of stars in the Milky Way galaxy.
Why is it difficult to see the motion of the stars from Earth?
~ It is difficult to see the motion of the stars from Earth because the stars are very, very far away from us.
How are great distances measured in space?
~ Great distances in space are measured using a special unit called a light-year. One light- year is equivalent to the distance that a beam of light travels in one year, or about 9.5 trillion kilometers.
How wide is the Milky Way Galaxy in light-years?
~ The Milky Way Galaxy is about 100,000 light-years wide.
| Approximate Time | 2 Minutes |
| Pre-requisite Concepts | Students should be able to define the following terms: Centauri, galaxy, and light year. |
| Course | Earth & Space Science |
| Type of Tutorial | Animation |
| Key Vocabulary | Centauri, galaxy, light year |
