Particulate materials constitute a large part of the natural world. At grand scales, these are the dusty nebulae clouds from which stars and planets are formed. At planetary scales, particulates constitute the rings of the giant planets, global dust storms on Mars and volcanic ash plumes on Earth. Particulate materials also make up the regoliths, soils, and sediments of solar system bodies. On Earth, they form the reservoirs for water, gas, and oil. Many scientific disciplines, engineering applications, and industrial pursuits involve the study or handling of particulate matter occurring in the form of powders and granules. In most cases, there is a need to be able to predict the behavior of these materials, and this in turn requires knowledge of the fundamental physics that causes particles to attract or repel one another. We will study these particulate materials while they are freely suspended and dispersed in reduced gravity in order to unmask weak forces.