Note: the Sesame server was modified on 22 August 2010; a new schema ( is used in the XML output. The output using the previous schemas (, and is still possible with a dedicated option.

1  What is Sesame?

Sesame is a name resolver which returns, from a string representing the designation of an astronomical object outside the Solar System, the position of that object in the sky and a few other details. It operates by querying the following databases: Simbad, NED , and VizieR.

Sesame can be accessed:

  1. by a form, where a name of an astronomical source (or of a file containing names) can be submitted; the options are available as buttons and checkboxes.

  2. by an HTTP-GET access to[/-opt][/~SNVA]?object_name[&other_object_name]...

    or at the mirror at

    where opt are output options detailed below, and ~SNVA indicate the possible choices of databases as Simbad, NED, VizieR, All the quoted databases, and the ~ which indicates to ignore any cached results. Without the A, the result of the first positive answer is listed only.

    This HTTP-GET access is available also as the sesame script included in the cdsclient package aimed at fast queries of the large survey from simple command-line interfaces well adapted to linux/unix scripts.

    An HTTPS endpoint is also available at[/-opt][/~SNVA]?object_name[&other_object_name]...

2  Output Options

The HTTP-GET protocol accepts the following output options:

The options may be combined, e.g. -oxpI asks for all identifiers in text/plain XML format.

3  Output Examples