Scientific Data Federation

Publisher Summary This chapter deals with the revolutionary changes in astronomy resulting from advances in digital astronomy and the application of Grid concepts. The astronomy community is interested in mining the individual datasets looking for patterns, but there is even greater interest in cross-correlating the datasets to find new phenomena. The construction of astronomy archive involves massive calculations that ingest, analyze, and categorize the instrument data, producing databases and files. Each astronomy archive covers part of the electromagnetic spectrum for a period of time and a subset of the celestial sphere. All the archives are from the same sky and the same celestial objects, although different observations are made at different times. Increasingly, astronomers perform multispectral studies or temporal studies, combining data related to the same objects from multiple instruments and archives. Cross-comparison is possible because data are well documented and schematized with a common reference frame and have clear provenance. The Virtual Observatory (VO)—sometimes also called the World-Wide Telescope—is under construction in many countries, which seeks to provide portals, protocols, and standards that unify the world's astronomy archives into a giant database containing all astronomy literature, images, raw data, derived datasets, and simulation data-integrated as a single intelligent telescope.