General Terms and Conditions

Updated at: 20 February 2024

The CDS Web Site, accessible at the address, previously, is the set of web resources implemented by Strasbourg Astronomy Data Centre for the collection and distribution of the astronomical data it manages. It is made up of several services in particular: SIMBAD, VizieR, and Aladin.

Any use of the CDS Web Site is subject to compliance with these general terms and conditions of use (GTCU).

Definitions used are:


The purpose of the CDS Web site is to provide public access to the data and metadata collected, generated, enhanced and structured by the Strasbourg Astronomy Data Centre.


The use of the CDS Web Site is free of charge.

Consulting and downloading data

Consulting or downloading the Datasets made available on the CDS Website does not require any prior registration. All Users must comply with the User licence specific to each Dataset.

The Data Sets must be cited in any work or product that uses them by including - if available - the DOI (Digital Object Identifier), as well as the source by mentioning the CDS service that supplied them, for example by one of these citations, and at least: "CDS/SIMBAD", "CDS/VizieR", "CDS/Aladin".

Any User may participate in the quality control of the Strasbourg Astronomical Data Centre's data by reporting errors, inaccuracies or additional information, and/or content that should not be included (illicit or contrary to the GTCU) via an Annotation or by e-mail (to

To be accepted and published by the CDS, Annotations must comply with the editorial policy of the Strasbourg Astronomy Data Centre.

Functionalities which Contributors can access

Any Contributor can submit Datasets to the Strasbourg Astronomy Data Centre, by depositing them and documenting them with metadata and documents (ReadMe, articles, tables, etc.) using the mechanisms in place (ftp repository, emails, etc.).

In order to be accepted and published by the CDS, Data Sets must comply with the editorial policy of the Strasbourg Astronomy Data Centre, in particular, they must be associated with a publication in a peer-reviewed journal. With the agreement of the Contributor, the CDS may complete and/or modify the metadata associated with the Data Set.

Code of Conduct and User Responsibilities

The CDS provides data submitted by Contributors which can be accessed for downloading via the CDS API or the platform's WEB interface.

The CDS Web Site is not intended to disseminate advertising data, data promoting private interests, data contravening public order or, more generally, illegal data. The administrators of the CDS Web Site may, if necessary, without prior notice, delete or make it impossible to access such data.

Contributors are solely responsible for the data and content that they submit for publication by the CDS.

When the Contributor submits for publication a Dataset including intellectual property rights that prevent Re-use, it mentions their presence in the documentation accompanying the Dataset. It shall indicate the identity of the natural person or legal entity holding such rights or, if this is not known, the identity of the person from whom the information in question was obtained.

Re-use of information

Reuse of the Datasets and contents made available on the CDS website must comply with the relevant licences (see next section).

The CDS, SIMBAD, VizieR, Aladin, Xmatch and CDSportal logos available on the CDS website are the property of the Strasbourg Astronomy Data Centre. They may be used by our partners in their communications media to refer to the CDS services to which they are attached, provided that the CDS is cited. Any other use, in particular for commercial purposes, without the prior written consent of the CDS is prohibited and will be considered an infringement of copyright.


Datasets containing only Public Information are distributed under an Open Licence or ODbL (see: or CC-BY.

Datasets containing non-public Information are distributed, where applicable with the agreement of the third party holding or co-holding the rights to the information, under an Open Licence or one of the licences compliant with open definition (see:

Datasets subject to a specific licence from the data Contributor are distributed in accordance with the licence rights. This specific licence is provided on the Dataset page.

Commitments and responsibilities

Quality of the service provided

Subject to the provisions of the following paragraph, CDS shall make all possible efforts to guarantee the availability of the CDS Web Site.

However, CDS also reserves the right to change, modify or suspend the CDS Web Site without notice for maintenance or any other reason it deems necessary. The unavailability of the CDS Web Site does not entitle the User to any compensation.

The CDS offers, at the Contributor's choice, the submission of Datasets and/or Annotations via the web interface of the CDS Web Site or through a programming interface (CDS API).

CDS provides access, at the User's choice, to the data sets via the CDS Web Site or via the CDS API.

CDS undertakes to take all necessary precautions to preserve the integrity of the data sets made available, and in particular to prevent them from being distorted or damaged.

Changes to the General Terms and Conditions

These Terms of Use may be amended at any time, without notice, to reflect changes to the CDS Website, changes in legislation or for any other reason CDS deems necessary.


Personal data

Consultation of published data and metadata does not require registration or authentication.

Submitting an Annotation or using a Personal Area may require authentication.

The personal data collected by the CDS is the information (user name, password, account creation date, last login (IP,data) and email address) required to create a Personal Area and to submit an Annotation.

The CDS undertakes to take all necessary measures to guarantee the security and confidentiality of the personal data of the User holding the Personal Area. These are never communicated to third parties, except in cases provided for by law.

The personal data collected by the CDS is the information (identifier, last name, first name, password, e-mail address, affiliation, research area) linked to the creation of a Personal Area, and/or for the submission of an Annotation.

The fact that you refuse to communicate all or part of the data does not affect the consultation of the CDS Website and does not result in a non-response to your requests for information. Refusal to communicate data relating to the use of a Personal Area or the submission of an Annotation will result in you not being given access to these services.

The recipients of personal data are authorised CDS staff. The information collected will only be communicated externally for the sole purpose of managing the CDS Website (e.g. audience measurement) or to comply with legal and regulatory obligations.

You have a right of access, rectification, opposition on legitimate grounds, limitation and deletion in relation to all data concerning you under the conditions laid down by law no. 78-17 of 6 January 1978 relating to information technology, files and freedoms and by the General Data Protection Regulation no. 2016/679. You have the right to give general or specific instructions relating to the retention, deletion and communication after your death of personal data concerning you in accordance with articles 32-I-6° and 40-1 of the amended law of 6 January 1978. You also have the right to lodge a complaint with a supervisory authority such as the Commission Nationale de l'Informatique et des Libertés (CNIL).

You may exercise these rights by contacting the Strasbourg Astronomical Data Centre (with the exception of the right to lodge a complaint, which must be exercised directly with a supervisory authority) by email at


The CDS Website uses technical cookies (session identification, etc.) in compliance with the conditions for exemption from Internet User consent defined by the "Cookies" recommendation of the French Data Protection Authority (CNIL).

Reference texts

Legal information

CDS Web Site

managed by the Strasbourg Astronomical Data Centre, hosted at the Observatoire Astronomique de Strasbourg, 11 rue de l'Université - 67000 Strasbourg, part of the Université de Strasbourg - national public establishment of a scientific, cultural and professional nature.

Director of Publication : Mark Allen (Director of the Strasbourg Astronomical Data Centre)


If you have any questions about these general terms and conditions of use, you can write to us at the following addresses :

Identification Numbers