1. Topic: Light Years Essential Question: How do scientists use light years to measure distances in our universe?

2. Topic: Light Years Essential Question: How do scientists use light years to measure distances in our universe? Astronomical Unit (AU) Used to measure distances in our solar system about 93 million miles which is the Earth to the Sun

3. Topic: Light Years Essential Question: How do scientists use light years to measure distances in our universe? Light Year The distance that light travels in one year Light travels at the fastest speed known in the universe It can go around the Earth 7 times in 1 second! the speed of light = 299 792 458 m / s

4. Topic: Light Years Essential Question: How do scientists use light years to measure distances in our universe? Light year Scientists use light years because stars are too far away to use: meters, kilometers, AU (Astronomical Unit) One light year is 10x10 16 meters long That’s 5.8 trillion miles!

5. Topic: Light Years Essential Question: How do scientists use light years to measure distances in our universe? If a star is 14 light years away, that means light has been traveling 14 years from that star to Earth That means this light started traveling when most of you were born

6. Now take some time… Take 2 minutes to go over your notes and highlight or underline the main ideas that answer the essential question, you should not highlight everything: Essential Question: How do scientists use light years to measure distances in our universe?

7. Time to use the left hand column You will now write your own questions using the verbs provided.

8. Topic: Light Years Essential Question: How do scientists use light years to measure distances in our universe? Astronomical Unit (AU) Used to measure distances in our solar system about 93 million miles which is the Earth to the Sun Choose one verb to write your question: Define Describe

9. Topic: Light Years Essential Question: How do scientists use light years to measure distances in our universe? Light Year The distance that light travels in one year Light travels at the fastest speed known in the universe It can go around the Earth 7 times in 1 second! Choose one verb to write your question: Define Describe

10. Topic: Light Years Essential Question: How do scientists use light years to measure distances in our universe? Light year Scientists use light years because stars are too far away to use: meters, kilometers, AU (Astronomical Unit) One light year is 10x10 16 meters long That’s 5.8 trillion miles! Choose one verb to write your question: Define Describe Explain

11. Topic: Light Years Essential Question: How do scientists use light years to measure distances in our universe? If a star is 14 light years away, that means light has been traveling 14 years from that star to Earth That means this light started traveling when most of you were born Choose one verb to write your question: Define Describe Explain

12. Time to use the left hand column You will now write your own questions using the verbs provided.

13. Now let’s write a summary Look at each question you wrote on your own, and answer each question in a complete sentence.