SIMBAD

CDS is experiencing a cybersecurity incident within its network of servers located in Strasbourg. Our teams are taking steps to assess and mitigate the issue. This includes taking some systems offline to help protect them. As a consequence, access to SIMBAD, VizieR, Aladin image surveys, X-Match and other services hosted on our main site cds.unistra.fr is currently degraded.

We apologize for any inconvenience this issue may cause. Our teams are doing their best to investigate the incident, and restore full access to the services located in Strasbourg as soon as possible.

This page provides some alternatives for accessing SIMBAD services in the meantime.

SIMBAD

At CfA Harvard

A mirror of the SIMBAD service is accessible at : https://simbad.cfa.harvard.edu/simbad/ It contains data ingested up to 2026-10-14.

A mirror of the SIMBAD TAP service is available here : https://simbad.cfa.harvard.edu/simbad/sim-tap/

At IDIA (South Africa)

A mirror of the SIMBAD service is accessible at : https://simbad.idia.ac.za/

A mirror of the SIMBAD TAP service is available here : https://simbad.idia.ac.za/simbad/sim-tap/

astroquery.simbad

You can configure astroquery to use a specific mirror to query SIMBAD.

The mirror site used by astroquery.simbad can be configured either:

1. In each script:

>>> from astroquery.simbad import Simbad
>>> my_simbad = Simbad()
>>> my_simbad.server = "simbad.harvard.edu"
>>> result_table = my_simbad.query_object("HD 8745")
>>> print(result_table)
 main_id        ra            dec       coo_err_maj coo_err_min coo_err_angle coo_wavelength     coo_bibcode     matched_id
               deg            deg           mas         mas          deg                                                   
--------- -------------- -------------- ----------- ----------- ------------- -------------- ------------------- ----------
HD   8745 21.72418762496 37.49220928213      0.0206      0.0205            90              O 2020yCat.1350....0G  HD   8745

(tested with Python 3.13.0 and astroquery v0.4.11)

2. Permanently on you machine:

To do so, go to the file ~/.astropy/config/astroquery.cfg and edit the [simbad] section. There should be a commented line:

#server = simbad.cds.unistra.fr

Replace by:

server = simbad.cfa.harvard.edu

Troubleshooting: if the file is not there, you might have changed the default location for astropy configuration files. You can find yours with:

from astropy.config import get_config_dir_path
print(get_config_dir_path())

Other services

You will find fallback information for other CDS services on this page.