Multi-day evaluation of space domain awareness architectures via decision analysis and multi-objective optimization

The US Government is the world’s de facto provider of space object cataloging data, but it is challenged to maintain pace in an increasingly complex space environment. This work advances a multi-disciplinary approach to better understand and evaluate an underexplored solution recommended by national policy in which current collection capabilities are augmented with non-traditional sensors. System architecting techniques and extant literature identified likely needs, performance measures, and potential contributors to a conceptualized Augmented Network (AN). Multiple hypothetical architectures of ground- and space-based telescopes with representative capabilities were modeled and simulated on four separate days throughout the year, then evaluated against performance measures and constraints using Multi-Objective Optimization. Decision analysis and Pareto optimality identified a small, diverse set of high-performing architectures while preserving design flexibility. Should decision-makers adopt the AN approach, this research effort indicates (1) a threefold increase in average capacity, (2) a 55% improvement in coverage, and (3) a 2.5-h decrease in the average maximum time a space object goes unobserved.

Space–Object–Landscape

This chapter interrogates a number of normative assumptions about “landscape” as an art-historical category current in the discipline. It proceeds by means of some very diverse thought-objects significantly separated by time and space—Chinese pagoda paintings found in the Dunhuang caves that are simultaneously concrete poems, British stone circles such as Stonehenge and standing crosses including that at Bewcastle, Roman wall paintings from Pompeii—because the issues are not specifically historical or historicist but rather more broadly conceptual and span the archaeological history of art from the Neolithic to modernity, not least interrogating certain practices in contemporary earth art. The intent is to interrogate what is meant by ‘landscape’ when treated as an art-historical category.