Presentation suitable for 4th-6th grade students obout finding planets around other stars, transits, and NASA's Kepler mission.

1. Exoplanets:
Finding Other Worlds Around
Other Stars
Paul Green
Center for Astrophysics

2. • What's the nearest star?
• Different kinds of stars
• hot and cool
• large and small
• far and near
• Difference between a star and a planet?
• Stars shine, planets don't
• So why can we see planets?
• There are different kinds of planets too!

3. Our Solar System
(Comparing Sizes)

4. Terrestrial (Rocky) Planets

5. Gas Giant Planets

6. Planets’ Distances from the Sun

7. How the Solar System Formed
About 5,000,000,000 years ago

8. Why do you think the rocky planets
are close to the Sun, and the gas giants far
away?

9. Exoplanets
Do you think there are planets around
other stars?

11. Finding Exoplanets
Like a mosquito near a far away
headlight, planets around other stars
are too faint to be seen.
So how can we find them?

12. TIME
BRIGHTNESS
0
0
Imagine you have a light sensor
aimed a lamp.
What would the transit of a book look like if you
made a graph of brightness vs time?

13. Like this?
TIME0
0
BRIGHTNESS

14. What would the transit of a planet look like if
you made a graph brightness vs time?
TIME0
0
BRIGHTNESS

15. TIME0
0
This is a “light curve.”
How are the planet’s size and orbital period
shown in the light curve?
BRIGHTNESS

17. What’s This?

19. NASA’s Kepler Mission

20. A Kepler Planetary Transit Lightcurve
3.2 day period
5 hour eclipse

21. 21
Transiting Planets pre-Kepler
Orbital Period in days
SizeRelativetoEarth

22. 22
22
Transiting Planets as of June 2010
Data: May-Sep 2009
Orbital Period in days
SizeRelativetoEarth
Jun 2010

23. 23
Transiting Planets as of Feb 2011
Q0-Q5: May 2009 - Jun 2010
Orbital Period in days
SizeRelativetoEarth
Jun 2010 Feb 2011

24. 24 Orbital Period in days
SizeRelativetoEarth
Transiting Planets as of Dec 2011
Q0-Q6: May 2009 - Sep 2010
Jun 2010 Feb 2011 Dec 2011

27. Different Types of Stars
Do blue stars always look fainter than red stars?

28. 28

29. What’s Next?
• Kepler has discovered thousands of planets, now what?
• There are big surprises, like gas giants in close orbits,
and enormous super-earths in large orbits.
• Time to search for signs of life!
• Giant telescopes are being built right now!

31. Habitable Zone