Some transformative impacts of computer science on astronomy Roger F Malina Observatoire Astronomique de Marseille Provence (OAMP) President Leonardo/OLATS: Observatoire Leonardo des Arts et Technosciences

Three areas Virtual Observatories –Data paid for by tax payers is public –Few astronomers now take their own data Scientific Simulation –The Simulation is the Theory Scientific Visualisation –Most data is mediated by computerised instruments –How to make data ‘intimate”

The Hubble Deep Field

Virtual Observatories 75% of Hubble Telescope publications come from scientists ‘mining’ the archive Most astronomers no longer “observe” New “fields: “Multi-wavelength astronomy” New professions: Data Analysts –Cf the 19 th century “calculators” Dan Boorstin: Epistemological Inversion –Data Poor to Data Rich with respect to Theory

Virtual Observatories Rebirth of amateur astronomy –NASA public data release policies ( 6 months) “Crowd sourcing” projects: –Berkeley Open Infrastructure Consortium Stardust, Martian Craters…… Petabyte revolution: “end of theory” –Statistical analysis of very large data sets –database science –Correlations, trend analysis,

The “Millenium Simulation”

Scientific Simulation Many problems not amenable to “compact predictive descriptions” cf E=MC2, F=MA Complex systems, chaotic systems, many body problems, Stellar evolution, planetary formation, structure formation in universe The Simulation is the Hypothesis

Scientific Simulation C Hayles: retrodiction versus prediction –S Kauffman : Phenomena “beyond prediction” – Galilean Fallacy: causality Search for “critical comparisons” Comparison of Computer Codes Problem of non unique solutions –Cf “inversion’ problem. Same phenomena may have multiple explanatory simulations

Visualisation, Sonification:\ Making data intimate

Scientific Visualisation All astronomical data is now digital –Kodak has stopped making photographic plates for astronomers The majority of astronomical data comes from light/energy “invisible” to humans Ontological challenge: –We have no sensory experience with the phenomena we study –How to do ‘ground truth”

Some Impacts of Computer Science on Astronomy The scientific method is changing – scientific simulation as the explanation The content of astronomy is changing –New problems can be attacked –Coupling to government/industry funding The profession of astronomer is changing –Social organisation of astronomy..internet.. –New opportunities for art-science collaboration