THE discussion on this subject arranged by the Faraday Society excited great interest, and the collected papers contain much that is of value. Whilst most of the speakers dealt with heterogeneous ...

Sedimentary rocks are made up of pieces of older rocks (igneous, metamorphic, and sedimentary) and organic remains (shells, bone, etc.). When rocks break apart from erosion they are transported by ...

One main goal of NASA's Mars 2020 mission is to determine when conditions on the planet were conducive to the formation of liquid water. Hence the target Jezero crater, seemingly a lakebed with a ...