The URIs in this list are the namespace URIs for AstroGrid schemata that are stable and published. The hyperlinks in the list point to the schema documents (.xsd, .wsdl); the target URLs of the hyperlinks are the location URIs of the schemata.
You may find this index in two places. On AstroGrid's central software-site (software.astrogrid.org), the location URIs are very stable, and are ideal for use in the schemaLocation attributes of XML documents. On AstroGrid's development site (www.astrogrid.org/maven), in the section devoted to the contracts Maven-project, the location URIs change with every new version of that project and are not suitable for use in instance documents.