Resubmit, slight changes to abstract. 835853410 Assigned ID: 687 ----- Attempting Submission 1 (Fri Apr 10 19:03:29 GMT 2015) ----- HST Phase I Proposal 687 (HST_Turnbull_Sparks.apt) successfully submitted. Receipt: # 687-1 ----- Attempting Submission 2 (Fri Apr 10 23:37:15 GMT 2015) ----- There is a growing impetus for spacebased missions to directly image and characterize Earth-like, and larger, exoplanets orbiting nearby sunlike stars. The target lists for all such missions form a well-defined sample that, by astrographical and astrophysical necessity, cannot change except around its periphery according to the details of mission performance. Advance characterization of confounding background sources in near-future planet hunting fields has the potential to critically impact target selection and observing strategy. HST offers the most sensitive means and highest angular resolution with which to understand the faint background surrounding these important targets. To help lay the groundwork for exoplanet imaging missions, we propose an archival HST wide field imaging proposal to characterize the Galactic and extragalactic background for the highest priority exoplanet imaging targets. For the 77 highest priority targets of recent mission concept studies (d<15pc), 25 have wide field imaging in the Hubble Legacy Archive. The stars are typically high proper motion with substantial displacement between the archival data and their future locations. We will identify where the present and near-future target fields overlap with this archival data, and which target fields require additional observations. We will then carry out a detailed analysis of star and galaxy counts and colors for the environments of the target stars. After demonstrating the utility of the HST archival data in preparing for direct imaging studies, this work is expected to lead to a Legacy proposal to study all targets in detail and propose for additional observations where necessary. EXTRA-SOLAR PLANETS 0 Regular false false false false false SUPPORTED