An overview of the Kepler mission, it's exciting new discoveries and the ever-growing variety of strange and wonderful worlds that populate our galaxy.

1. The Kepler Mission
and
The Search for Exoplanets
Professor Thomas Madigan

2. Exoplanets: Extra solar planets or planets
in orbit around other stars

3. Prime directive: to find Earth-like planets
in the habitable zone of sun-like stars
Sunlike stars:
G class, main sequence stars
Motivation: to complete the Copernican
Revolution, to find our reflection in the
cosmos

4. Mission Goals:
Using the transit method and by taking large
samplings of data, investigate the range
and configuration of planetary systems of
target stars in the Lyra / Cygnus region of
the sky
Determine the percentage of terrestrial and
larger planets that are in or near the
habitable zone of a wide variety of stars
Estimate how many planets exist in multiple-star
systems and, with that, come to a
conclusion regarding their sizes, shapes,
mass and densities

5. Habitable Zone:
directly linked to a star’s intrinsic luminosity,
it is the region around the star where water
can exist in a liquid state
For cooler, less luminous stars, it is closer
to the star and less extensive
For hotter, more luminous stars, it is further
out and more extensive

8. Solar System Temperatures and
Environmental Parameters
Planet Distance (AU) Temperature (K) Notes
Mercury 0.387 633.65
Venus 0.723 463.59
Earth 1.000 394.19 Habitable zone (inner boundary)
1.116 373.14 Water transitions from gas to liquid
Mars 1.523 319.41
Ice Line 2.100 272.02 Habitable zone (outer boundary) - water transitions from liquid to solid
Asteroid Belt 2.800 235.57 Asteroid belt center of mass and semi-major axis of Ceres
Jupiter 5.204 172.80
Saturn 9.582 127.34
Uranus 19.229 89.89
26.200 77.01 Nitrogen transitions from gas to liquid
Neptune 30.103 71.85 Possible liquid nitrogen geysers on Triton
Pluto 39.481 62.74

9. Why Sun-like stars?
Life expectancy of G-class stars is
measured in tens of billions of years
Habitable zone is far enough from the
host star where life-inhibiting
gravitational tidal-locking won’t occur

12. The Kepler Instrument
Launched on March 6th, 2009, Kepler is a 1-meter
class, orbiting visible-light observatory

13. The Kepler Instrument
Using the transit method and modern, state-of-the-
art Photometry, simultaneously
monitors the light curves of over 100,000
target stars
Necessary sensitivity and precision: to
accurately measure variations in intensity
by one part in 10,000 for earth-like planets
in the habitable zone of sun-like stars

14. The Kepler Instrument

15. The Kepler Instrument
Candidate stellar and planetary systems are
confirmed using large, ground-based
telescopes

16. Kitt Peak National Observatory

17. The 4-Meter Mayall Reflector
at Kitt Peak

18. The 4-Meter Mayall Reflector
at Kitt Peak

19. The Transit Method
We can’t visibly “see” the planet so how
do we detect its presence?
– measure variations in the star’s intensity as
the planet transits the star
– for earth-like planets in the habitable zone
of sun-like stars, a sensitivity and accuracy
of one part in 10,000 is necessary

20. The Transit Method

21. The Transit Method

22. The Transit Method
We can’t visibly “see” the planet so how
do we determine the composition of
the atmosphere?
Changes in the star’s spectra as the planet
transits the star will reveal the composition of
the planet’s atmosphere

23. Recent Findings
Kepler 22-b
2-earth radii “Super Earth”
– 8 times the earh’s mass
– 2x the gravity
– believed to harbor abundant water

25. Recent Findings
Kepler 16 and 16-b
“Tatooine”-like system