1. Summary Thoughts - Scientific Wesley A. Traub Chief Scientist, NASA’s Exoplanet Exploration Program Jet Propulsion Laboratory, California Institute of Technology Ozma 50 Workshop Green Bank, West Virginia 15 Sept. 2010

2. SETI Radio survey 1-15 GHz, full spectrum, continuous observation Sounds wise, not precluding any spectral region “Expect the unexpected” philosophy Optical survey Visible or near-infrared Could detect a beacon Could have a radio signal in parallel, or be the signal itself

3. SETU or SETSOL Direct Imaging of Nearby Exoplanet Systems Must be in space Probably optical (possibly infrared) Could happen in early 2020s Would give images of planets (Earth-size and larger) and exozodi Image from HZ to beyond Jupiter Would give spectrum of each pixel Detect H20, O2, O3, CO2, CH4, land plants, atmosphere, rotation, etc.

4. Drake Equation Term n e Preliminary derivation of n e from Kepler data 42 days of data published so far Select subset of exoplanets, complete in the 2-17 day period range Select Jupiters in this complete sample Compare to expected number in period & mass/radius range Get excellent agreement; good sign!

5. Exoplanet Mass-Radius Kepler, Borucki et al 2010 Cumming et al 2008 dN/dln(M) ~ M -0.31 Ref.: Seager, Kuchner, et al. 2007 “Jupiters” “Earths”

6. “Jupiters”

7. “Ice giants” “Earths & SuperEarths”

8. nene Preliminary derivation of n e from Kepler data 42 days of data published so far Select subset of exoplanets, complete in the 2-17 day period range Select Jupiters in this complete sample Compare to expected number in period & mass/radius range Get excellent agreement; good sign! Fit ice-giant trend Assume smallest radius bin is not complete Extend trend to 1 Earth radius Count expected number of 1-2 Earth-radius planets Extrapolate to HZ planets (Venus to Mars distances, 1-2 Earth radii) Compare to sample size Derive estimated ne, find a large number.