Presentation on theme: "A Search for Earth-size Planets Borucki – Page 1 KEPLER; Data Validation and Follow Up Observations CoRoT Symposium W.J. Borucki & the Kepler Team 5 February."— Presentation transcript:
A Search for Earth-size Planets Borucki – Page 1 KEPLER; Data Validation and Follow Up Observations CoRoT Symposium W.J. Borucki & the Kepler Team 5 February 2009
A Search for Earth-size Planets Borucki – Page 2 Key Ground Segment Roadmap Functional Interface Primary Command Flow Primary Telemetry Flow Project Scheduling Services Navigation (NAV) JPL Deep Space Mission Systems Mission Operations Center LASP Data Management Center STScI Flight Planning Center BATC Science Operations Center ARC Stellar Classification Program Mission Management Office ARC Science Office ARC Follow-up Observing Program BATCLASP ARCJPL Sci TeamSTScI
A Search for Earth-size Planets Borucki – Page 3 Black level correction Quarterly Processing DMC Ground-based Follow up Observing SOC Smear, flat field, dark current, nonlinearity, cosmic ray correction OAP and DIA photometry to generate flux time series Pre-search data conditioning to remove systematic errors Transiting and reflected- light planet search Focal Plane Characterization Data Validation SOC data store SOC Data Store Photometer performance assessment SOC data store SOC Data Store
A Search for Earth-size Planets Borucki – Page 4 Methods of Data Validation Using Kepler Data Rule out statistical fluctuations in the data, accept only signals that show 3 or more transits and that have a total signal-to-noise ratio that exceeds 7 sigma. To rule out small stellar companions of the target star, check for secondary eclipses and determine if the transit characteristics are appropriate for a planetary companion. Modeling effort will be used to distinguish stellar binaries from stars with planets. Check for background binaries that are in the target aperture; measure the movement of the image centroid before, during, and after the transit. This test is expected to rule out the hundreds of binary signals expected from background stars. The precision of the measurement depends on the stellar fluxes and positions but can be better than 0.01 pixel; i.e., 0.04”.
A Search for Earth-size Planets Borucki – Page 5 Ground-based Follow Up to Eliminate False-Positive Events Those candidates that pass DV are examined using ground-based telescopes and radial velocity spectrometers. 1.Medium precision RV is used to rule out any remaining stellar companions. 2.High spatial resolution imaging is used to check for nearby stars that are in the aperture. (apertures depend on magnitude but are ~ 36 sq arc sec.) 3.If no confounding stars present, then the candidate observed with a large telescope such as Keck, HET, or Willilam Herschel for high precision observations to get the planet mass or an upper limit to it. 4.If there are some stars in the aperture, then the photometric observations are employed to look for the transit by one of the confounding stars. (Includes AO & HST observations for Earth-size candidates.) 5.If transit signal is not due to confounding stars, then the candidate is sent to a large telescope such as Keck, HET, or William Herschel for high precision observations to get the planet mass or an upper limit to it.
A Search for Earth-size Planets Borucki – Page 6 Coordination of Ground-based Follow Up Observations Candidate Follow up –Algorithm ranks several hundred candidates to set their priority –Observers assemble to discuss & agree on targets –Target information (RA, dec, mag, SpT, variability, ephemeris) sent to coordination website Coordination Web Site –Organized by follow-up target and by observation request –Contains all the information on the targets as requested by observers –Contains intermediate results from observations and whatever compact, reduced data sets are required by the Follow up Observers Group –Voluminous data is referenced by links to observers’ home facilities Co ordination data base –Operated by the Follow-up Coordinator to schedule and track status of observations requested by the PI and Science Team Results returned to Science Office Science team meets to discuss results & make announcements
A Search for Earth-size Planets Borucki – Page 7 DATA RELEASE POLICY All discoveries are released after the team meets to discuss the evidence and NASA HQ is informed. Pixel-level data and light curves are released with each discovery.