High Definition Astrometry (0.1 - 1.0 micro-arcseconds) will open a new window into neighboring planetary systems. The realm of temperate terrestrial worlds can be surveyed. This includes Earth Analogs, thereby allowing the value of eta-Earth to be directly determined. It will be able to confirm the existence of Radial Velocity (RV) planets.
The full text of this article is only available in PDF format: