We only see the surface of things.  Even our most sophisticated remote sensors on high-tech spacecraft can only sense the uppermost surface of unexplored worlds.  The quest to explore and characterize many other worlds using remote sensing is complicated by the fact that impact craters of all sizes continually redistribute materials while physically and chemically reprocessing it.  The soil and debris that forms the surface of a planetary body nevertheless reveals much about the body and its recent history.  Small fresh craters strip away the upper space weathered soil, and large craters probe into different unseen layers of the interior.  Large impacts also sometimes launch meteorites or other rocks that eventually make their way to Earth.  Some information such as bulk compostion or mineralogy comes easily from the remote measurements; other information such as origin and evolution of the body can require years of detailed analyses of pieces of the puzzle to even ask the right questions.  There is some information about minor elements or isotopes that just is not reasonably possible with remote sensors and requires a sample to be returned to Earth for study.  Sample analyses and remote sensing thus play intertwined and complimentary roles in understanding other bodies of the Solar System.  Armed with detailed spectral analyses of meteorites and returned lunar samples, Dr. Pieters will discuss the most recent discoveries and issues using similar remotely sensed data for airless planetary bodies such as the Moon and small bodies of the Solar System which are particularly vulnerable to alteration in the space environment.