Motivation

The motivation to build CAS (catalog access service)

• Any serious VO application requires access to data and ability to do basic operations with them like cone search, crossmatch queries. So, we need to develop a system, which hosts catalogues and their metadata.
• Up To the moment there is no such catalog storing system. However, there are good examples like CASjobs and Openskyquery, but they are not public and have several disadvantages.

So the main idea is:

• Build the system allowing to store almost any astronomical catalogue, put it in the system using simple API, get the data and metadata about it.
• That system should allow to create the VO services on it, and build some external interfaces too.

Finally, we should say that creating of CAS is mainly preparation of the VO work, preparation to enable even such simple things like cone search based on Q3C.