Science is driven by our desire to understand things. In some cases, where it requires significant effort and investment to develop systems that can understand new things, science benefits from a game plan that the community of researchers focused on a particular niche can rally around, even if they don't necessarily agree on the details. In astronomy and space science, those game plans typically take the form of Decadal Surveys, produced by the National Academies to define the path forward in a specialization or sub-field.