1. Kepler’s Laws

2. Science Starter
After reading the article, write one or two paragraphs:
What is your opinion on it?
What is an “orbit”?
Name 2 things that orbit, and tell what they orbit around

3. HOMEWORK
Get progress reports signed
No other homework

4. Standard 1.1.1: KEPLER’S LAWS
How do planets move?

5. WHO IS KEPLER?
While watching the video, write down 3 interesting facts about Johannes Kepler
Video Link

6. KEPLER’S LAWS
Kepler created 3 laws that discuss how Earth and the other planets move

7. 1ST LAW: LAW OF ELLIPSES
Planets move in elliptical orbits with the sun at one focus

8. WHY AN ELLIPSE?! The shape is determined by 2 focal points
The sun has such a large gravitational pull that the sun is at one focus and their other is empty!

9. ROTATION VS. REVOLUTION spinning orbiting 24 hours 1 year
QUICK REVIEW
ROTATION VS. REVOLUTION spinning orbiting 24 hours 1 year

10. 2ND LAW: LAW OF EQUAL AREAS
Planets speed up when they are closer to the sun because of the sun’s gravitational pull

11. 2ND LAW: LAW OF EQUAL AREAS
Which is the faster side?

12. BARYCENTER Barycenter – the center of mass between 2 points
All bodies (including the planets and the sun) revolve around a barycenter

13. CENTER OF MASS

14. 3RD LAW: LAW OF HARMONIES
The time it takes to revolve around the sun is proportional to the distance from the sun
The further from the sun, the longer the revolution

15. JUST LIKE A TRACK!

16. Plot a graph of the DISTANCE from the SUN (on the x-axis) against the TIME for one ORBIT (on the y-axis)

17. EXIT TICKET Write a 5 minute essay to answer the burning question:
How do planets move?
Take the full 5 minutes to write your answer, and try to include information about as many of Kepler’s Laws as you can!

18. Video
h?v=f6foCDF6zI0

19. FINISHING UP FROM YESTERDAY
Complete solar system drawing