Space-Time Metadata for the Virtual Observatory

Abstract.

We discuss the hierarchy of objects that are to contain the metadata pertaining to space and time for the Virtual Observatory. The design needs to be sufficiently general that it can adequately represent the many coordinate systems and conventions that are in use in the community. On the other hand the most basic requirement is that the space-time metadata for queries, for resource descriptions, and for data be complete and self-consistent. If these two requirements are met, the VO should be able to respond to a query in any coordinate system and deliver data from depositories with a variety of native coordinate systems.