  Astrometric Science and Technology Roadmap for Astrophysics (ASTRA) is a
bilateral cooperation between China and Italy with the goal of consolidating
astrometric measurement concepts and technologies. In particular, the
objectives include critical analysis of the Gaia methodology and performance,
as well as principle demonstration experiments aimed at future innovative
astrometric applications requiring high precision over large angular
separations (one to 180 degrees). Such measurement technologies will be the
building blocks for future instrumentation focused on the "great questions" of
modern cosmology, like General Relativity validity (including Dark Matter and
Dark Energy behavior), formation and evolution of structure like
proto-galaxies, and planetary systems formation in bio compatibles
environments. We describe three principle demonstration tests designed to
address some of the potential showstoppers for high astrometric precision
experiments. The three tests are focused on the key concepts of multiple fields
telescopes, astrometric metrology and very fine sub-pixel precision (goal:
<1/2000 pixel) in white light.
