The Emerging Virtual Observatory. The Virtual Observatory (VO) is a federative project which has independently been accorded high strate- gic priority by the astrophysical communities in a significant number of astronomically active nations across the globe (e.g. the USA, Canada, the UK, the Netherlands, Germany, India, ...). These efforts have rapidly coalesced into a coordinated approach to building a Global Virtual Observatory. This will be a distributed web- or grid-like computational structure which links the data archives of all major astro- nomical telescopes, both ground- and space-based. A user anywhere in the world will be able to formulate queries which require the location and interrogation of disparate and distributed archives without any detailed knowledge of the existence or properties of those archives. While almost all VO work is currently directed towards observational datasets, there is also considerable demand for simulation datasets which are essential for interpretation of the observations. This is demonstrated by the many Virgo images and the many independent analyses of Virgo simulation data which have appeared in popular and professional journals. Virgo-developed simulation codes are also in regular use at many institutions worldwide that have no direct relation to the consortium. However, Xxxxx’s VO functionality at present is rudimentary, with extremely limited access to data and information. (eg see the current Virgo down-load site at xxxx://xxx.xxx-xxxxxxxx.xxx.xx/Virgo/). AstroGrid is a £3.7M project (xxxx://xxx.xxxxxxxxx.xxx/) which is developing a working datagrid for key selected databases, with associated data mining facilities, with rollout iterations through to late 2004. It is part of the worldwide drive towards the VO concept, and can be seen as the UK’s contribution to this vision. However, it is both wider and more focused than other initiatives. It is wider in that it covers Astronomy, solar Physics, and space plasma (solar terrestrial) Physics, and covers all wavelengths from radio to X-ray. The project is also part of a coherent UK e-science programme, with links to projects in particle Physics, bio-informatics, and basic grid technology development. AstroGrid is, however, focused in that it is developing a fully functional (but limited in scope) VO on a short timescale, to enable early scientific exploitation of the system, and provide technological lessons to better inform the deployment of larger scale VO systems. This is requiring a concentrat...
