KEPLER Discovery Mission # 10

1. KEPLER Discovery Mission # 10 William Borucki, PI NASA Ames

2. KEY QUESTIONS: • Are terrestrial planets common or rare? • How many are in the habitable zone? • What are their sizes & distances? • Dependence on stellar properties

3. SCIENTIFIC GOALS • Determine the frequency of terrestrial and larger planets in or near the habitable zone of a wide variety of stellar spectral types • Determine the distribution of sizes and semi-major axes of these planets • Identify additional members of each photometrically discovered planetary system using complementary techniques • Determine the distributions of semi-major axis, albedo, size, and density of short-period giant planets • Estimate the frequency of planets orbiting multiple star systems • Determine the properties of those stars that harbor planetary systems

4. KNOWN EXTRASOLAR PLANETS

5. DOPPLER VELOCITY MEASURMENTS

8. MISSION DESIGN KEPLER: A Wide FOV Telescope that Monitors 100,000 Stars for 4 years with Enough Precision to Find Earth-size Planets in the HZ Use transit photometry to detect Earth-size planets • 0.95 meter aperture provides enough photons • Observe for several years to detect the pattern of transits • Monitor stars continuously to avoid missing transits • Use heliocentric orbit • Get statistically valid results by monitoring 100,000 stars • Use wide field of view telescope • Use a large array of CCD detectors 21 CCD Modules are the Heart of the Kepler Mission

9. REQUIRED SENSITIVITY • ∆L/L = area Earth/area Sun = 1/12,000 = 8x10-5 • Require total noise to be <2x10-5 for 4-sigma detection in 6.5 hours • Three sources of noise and their contributions: - Stellar variability:<1x10-5, typically for the Sun on timescale of ~1/2 day - Shot noise:1.4x10-5, in 6.5 hr for mv=12 solar-like star and 0.95-meter aperture • Instrument noise: <1x10-5, including detector dark current, electronics read noise, thermal effects, spacecraft pointing jitter, and shutterless operation. • Detector of choice: array of 42–2kx1k CCDs with 27µm pixels and dual readout • Thinned, back-illuminated, anti-reflection coated • Limiting bright magnitude of mv=9 and full-well depth of 106 e-requires: - Defocus image to 5 pixel square and readout every 3 seconds.

10. MEASUREMENT TECHNIQUE • Use differential photometry (common mode rejection): - Brightness of each star is re-normalized to the ensemble of thousands of stars in each half of each CCD & readout with a single amplifier; • Transits only last several hours: - Long term photometric stability not necessary; • Defocus the star image to five pixel square: - Mitigates saturation (109 e-/hr) and sensitivity to motion; • Control pointing to 3 millipixels (0.01 arc sec); - Star images remain on the same group of pixels, eliminates effects of inter-pixel variations in sensitivity; • Operate CCDs near full-well capacity: - Dark current and read-noise effects become negligible; • Place the photometer in a heliocentric orbit (SIRTF-like): - Provides for a very stable thermal and stray light environment.

11. SCIENCE DRIVER • Statistically valid result for abundance of Earth-size planets in habitable zone # of Planet Detections Orbital Semi-major Axis (AU) Expected # of planets found, assuming one planet of a given size & semi-major axis per star and random orientation of orbital planes.

12. SCIENCE TEAM William J. Borucki, PI, and David Koch, Deputy PI Theoretical Studies • Alan Boss, Carneige Institute Wash. • Jack Lissauer, NASA Ames Mission Operations • Donald Brownlee, U. of Washington • Yoji Kondo, NASA GSGC General Overview • John Caldwell, York U. • David Morrison, NASA Ames • Tobias Owen, Univ. Hawaii • Harold Reitsema, Ball Aerospace Co. • Jill Tarter, SETI Institute Education and Public Outreach • Edna DeVore, SETI Institute • Alan Gould, Lawrence Hall of Science Stellar Occultations & High-Precision CCD Photometry • Timothy Brown, HAO, UCAR • Edward Dunham, Lowell Obs. • John Geary, SAO • Ronald Gilliland, STScI • Steve Howell, U. Cal., Riverside • Jon M. Jenkins, SETI Institute Doppler Velocity Planet Searches • William Cochran, UTexas • David Latham, CfA, SAO • Geoff Marcy, U. Cal., Berkeley Stellar Variability • Gibor Basri, U. Cal., Berkeley • Andrea Dupree, CfA, SAO • Dmiter Sasselov, CfA, Harvard

13. OPERATIONS ORGANIZATION

14. EDUCATIONAL & PUBLIC OUTREACH Formal Public Outreach • Amateur Astronomers -kit -ephemerides -TransitSearch • Broadcast television program • STARDATE radio programs Informal • NewGEMS strand: Space Science“ Finding New Worlds” • FOSS Teacher workshops • Space Place activities • Hands On Universe Planet-finding for high school • Kepler-CAM (Underserved/ minority colleges) • Multi-media planetarium program (large dome) • Interactive planetarium program (small dome) • Kepler CD-ROM • Exhibit Orrery Transit Model Lessons, simulations — Website — Information, data

15. SCHEDULE & MISSION STATUS CCD Detectors are arriving from both vendors Optics are on order Preparing for the first major review Bill Borucki

16. VALIDATION OF DISCOVERIES • Signal to Noise Ratio (SNR) > 7 to rule out statistical fluctuations • Three or more transits to confirm orbital characteristics • Light curve depth, shape, and duration • Image subtraction to identify signals from background stars • Radial velocity Medium resolution to rule out stellar companions High resolution to measure mass of giant planets • High spatial resolution to identify extremely close background stars