Every larger area consists of various bedrock remnants or is a mixture of rocks ejected from unknown distances as a result of impacts of various magnitudes. The largest impact bodies also hit the lunar surface excavating, breaking, milling, mixing, melting and even evaporating and throwing out essential parts of the lunar crustal rock material and possibly even some material from the mantle. Ring structures on the lunar surface must be studied together with gravity, topography, composition and other data sets. Various crater and ejecta blanket details let to identify processes involved in crater, and surface, formation, aging and deformation. The comparative analysis of the elements, mineralogy and morphology of the lunar surface will crucially constrain the hypotheses on the geological and geochemical evolution of the Moon.
Spectral signatures make it possible to measure differences in surface composition.
Analysing their distribution is essential to approach the first half billion years of the lunar history and to determine the origin and deformation of highland crust during that period of time. MORO instruments and mission MORO is proposed as a lunar orbiting observatory capable of fulfilling basic gaps of lunar science, still left open after Apollo and the recent, technologically-oriented Clementine mission . It will perform remote sensing observations of the lunar surface and measurements of the global topography and gravimetry of the Moon. The observatory is designed to house several instruments working in synergy to address the outstanding questions on origin, evolution and future exploration of the Moon. Two possible MORO versions have been identified, involving spacecraft of different size and complexity and payload composition.