Nuevo Observatorio Virtual Argentino

Service Name:

Argentine Virtual Observatory TAP service

Description:

The Argentine Virtual Observatory's TAP end point. The Table Access Protocol (TAP) lets you execute queries against our database tables, inspect various metadata, and upload your own data. It is thus the VO's premier way to access public data holdings. Tables exposed through this endpoint include: data from the chipa schema, data from the d18gx schema, wr35a from the fcaglp2 schema, hd165052 from the fcaglp schema, data from the gcss schema, data from the spec schema, columns, groups, key_columns, keys, schemas, tables from the tap_schema schema, data from the vvvsurvey schema.

Contact:


Nova Team
nova@conicet.gov.ar
IAFE

Access using:

  • tap the interface to this site's Table Access Protocol service. This protocol is best accessed using specialized clients or libraries. In such clients, you can find this service by its IVOID, ivo://ar.nova/tap, or access it by entering its base URL http://nova.fcaglp.unlp.edu.ar/__system__/tap/run/tap directly. Using an XSL-enabled web browser you can, in a pinch, also operate the service without a specialized client.

Documentation:

This service speaks TAP, a protocol designed to allow the exchange of queries and data between clients (that's normally something running on your computer) and servers (e.g., us).

You will want to use some sort of client to query TAP services; examples for those include:

  • TOPCAT (see in the "VO" menu)
  • TAPHandle (following this link should bring you to a page that lets you query this server) works completely within your browser,
  • pyVO (for VO support in python programs)

You can, in a pinch, use our service in an XML-enabled browser, too. Under Overview, look for the bullet point on tap and follow the link to "this service". Then, click on "New job..." in the job list, enter your query, click "Set query", then "Execute query". Reload the page you are redirected to now and then to see when your job is finished, then retrieve the result.

The queries this service executes are written an a dialect of SQL called ADQL. You need to learn it to use this service. See our ADQL tutorial. Also do not miss the local examples.

By the way, for quick ad-hoc queries from within a browser, our ADQL form service may be more convenient than TAP.

Also see the table metadata of the tables exposed here.

Local information: This service may put a much lower limit on uploads in sync queries than advertised in the table metadata. Unfortunately, current TOPCAT versions don't give terribly helpful error messages when the server rejects a query because the attached upload is too large (something like “Error writing request body to server“). If that happens to you, just switch to asynchronous querying (in TOPCAT, that's in the “Mode” combo box just above the query editor).

Issues

For information on our ADQL implementation, see the ADQL service info.

If multiple output columns in a query would end up having the same name, in the output VOTable they are disambiguated by appending underscores. This is in violation of the specification, but since fixing it would require rather intrusive changes into our software and it is not clear why one should want to use names when they are not unique to begin with, this will probably not be fixed.