  Long range observations in the field of astronomy have opened up our
understanding of the Solar System, the Galaxy and the wider Universe. In this
paper we discuss the idea of direct in-situ reconnaissance of nearby stellar
systems, using robotic probes. In particular, we consider what additional
knowledge can be learned that can only be obtained by such close encounters.
This may include calibration of existing measurements, detailed observations of
stellar winds, astrometry measurements of stellar parallax, refinement of our
understanding of physics through the use of long baseline interferometers. In
addition, getting close to an exoplanet will enable detailed knowledge of
planetary interiors, surface processes, geological evolution, atmospheric
composition and climate, internal seismology, detailed surface morphology and
even the speculative possibility of detecting the presence of microbial life,
detailed palaeontology or even indigenous life-forms. We argue that
astronomical remote sensing should be pursued in parallel with in-situ
reconnaissance missions by robotic probes, so that both can enhance the
discoveries and performance of the other. This work is in support of Project
Starshot; an effort to send a Gram-scale probe towards another star at 0.2c
within the next two decades, and return images and other data to the Earth.
Presented at the 47th IAA Symposium on Future Space Astronomy and Solar System
Science Missions. Session on Space Agency Strategies and Plans.
