1. Distances in the UNiverse
SPI Explain how the relative
distance of objects from the earth affects how they appear.

2. Learning Objective
At the end of the lesson, you will be able to answer the following question:
How does distance affect the size of objects in the universe?

3. TNReady Question

4. Answer
Correct Answer is F.
We would not be able to see the moon at all.
Explanation: The moon is sooooo much smaller than the Sun. If the moon were as far away as the Sun, it would be too small to see. We see the Sun because it is so massive in size.

5. Distance affects our Perception of Objects

7. Other Factors Affect our perception
We look for other cues around us to help make sense of what we are seeing.

8. Which center circle is larger. Which horizontal line is longer
Which center circle is larger? Which horizontal line is longer? Which running figure is taller?
They are the same.

9. Objects appear different sizes depending on your distance from them.
Would these two people see the object the same?

10. What about the universe?
Now that we understand how our perspective depends on the distance we are from the objects and other cues, let’s explore how this affects what we see in the sky.

11. Distances in the Universe Video Clip

12. Check for Understanding
Why do we use light years to measure distance in space?

13. Answer
Since the distances are so large, using regular numbers would get really confusing. And light is the fastest moving ANYTHING that we know. It makes sense to use light to measure the huge distances in space. If only we could really travel that fast…

14. Size Comparison
In case you needed some universal perspective…

15. Imagine…
What would it look like if the moon were replaced with planets from our solar system? Or the Sun??
Turn to your partner and share one prediction of how it would look different.

16. The Sun and our moon

17. The sun and our moon
Sometimes they appear the same size. Why?

19. Modeling
Groups of 3-4
Using two different sized balls, can you position them in the classroom to appear to be the same size?
Take a picture using your phone and to your teacher to show to the class.

20. Summary
Explain how the relative distance of objects from the Earth affects how they appear.
1. The farther away an object is, the ___________ it looks.
2. The closer an object is, the ____________ it appears.