Computational science has historically meant simulation; but, there is an increasing role for analysis and mining of on-line scientific data. As a case in point, half of the world's astronomy data is public. The astronomy community is putting all that data on the Internet so that the Internet becomes the world's best telescope: it has the whole sky, in many bands, and in detail as good as the best 2-year-old telescopes. It is usable by all astronomers everywhere. This is the vision of the virtual observatory -- also called the World Wide Telescope (WWT). As one step along that path I have been working with the Sloan Digital Sky Survey (especially Alex Szalay of Johns Hopkins) and CalTech to federate their data in web services on the Internet, and to make it easy to ask questions of the database (see http://skyserver.sdss.org). This talk explains the rationale for the WWT, discusses how we designed the database, and talks about some data mining tasks. It also describes computer science challenges of publishing, federating, and mining scientific data, and argues that XML web services are key to federating diverse data sources.

Jim Gray is part of Microsoft's research group. His work focuses on databases and transaction processing. Jim is active in the research community, is an ACM, NAE, NAS, and AAAS Fellow, and received the ACM Turing Award for his work on transaction processing. He edits a book series on data management, and is active in building online databases like http://terraService.Net/ and http://skyserver.sdss.org. Jim's home page is http://research.microsoft.com/~Gray/