Astronomical data archives that are participating in the Virtual Observatory (VO) can be discovered and queried by VO compliant software tools. seleste is a tool that uses VO standards and protocols to access archives that expose tabular data and query them using a uniform interface. Compared to applications designed to query specific datasets at a specific location, using pre-defined query forms, seleste allows ad-hoc queries against any discoverable archive, through a common interface. The architecture includes an application with a graphical user interface, a set of command line tools and a library, interoperating with VO services and applications.

In seleste graphical interface, a user can discover data archives and automatically display their metadata. For a selected archive, a user can construct a query in a graphical query builder by using the available columns in the data and by adding them into results and selection criteria lists. Queries can also be displayed and edited as text in the Astronomical Data Query Language (ADQL) and they can be saved and reloaded. One or more queries to an archive or multiple archives can be submitted to run asynchronously and their status can be monitored in a jobs display window. Upon completion of a query, the result is available to display, save, or transmit to other VO enabled applications. When supported by an archive, user data can be uploaded and combined in a query with other data in the archive.

In seleste command line interface a user can view the metadata of a service, submit ADQL queries and wait for results or retrieve them later. Queries can be typed directly or loaded as they were built and saved using the graphical interface. This interface is useful for batch processing that combines data retrieval and processing.

The seleste core is a Table Access Protocol (TAP) client API implemented as a Java library that can be used in developing applications with a TAP client component. The high level design is shown in the UML class diagram.