SIMBAD FAQ

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service.</p> </header> <div class="search-container" data-pagefind-ignore> <div class="modal-background"></div> <div class="search-form"> <input type="text" placeholder="Search terms..." /> </div> <div class="search-result hidden"> <div class="message">Sorry! No page matches the terms <code class="terms"></code></div> <div class="filters"></div> <ul class="results"></ul> </div> </div> <div class=" main-wrapper" > <main data-pagefind-body> <div class="pageDates"> <strong>Updated:</strong> <span title="August 01, 2024 - 13:48 UTC">August 01, 2024 - 15:48 CEST</span> </div> <h1 id="simbad-contents">SIMBAD contents <a href="#simbad-contents" class="quick-link" title="Quick link on this section."></a></h1> <details id="d3602181281"> <summary> Why is my paper missing from an object's bibliographic references? <a href="#d3602181281" class="quick-link" title="Quick link on this block."></a> </summary> <p>New links between papers and astronomical objects are added to SIMBAD on every working day by the CDS documentalists. Your paper might not yet appear in an object's bibliography for several reasons:</p> <ul> <li> <p><strong>The paper has not been fully processed yet.</strong> Papers are only processed by the SIMBAD team <em>after they get published by the journals</em>. The processing of a paper at CDS for its ingestion in SIMBAD involves several teams where documentalists, astronomers and engineers work together. The process is not a fully automated one, and depending on the complexity, quality and quantity of data, it can take several months.</p> <blockquote class="info"><p>See also "How do I check the status of a paper in SIMBAD?" in this FAQ, to find the current status of your paper.</p> </blockquote> <blockquote class="warning"><p>Be aware that preprints from arXiv are never processed in SIMBAD.</p> </blockquote> </li> <li> <p><strong>Not all journals are systematically processed in SIMBAD.</strong> The <a href="http://simbad.cds.unistra.fr/simbad/sim-display?data=journals"target="_blank" rel="noopener">list of journals and periodicals</a> scanned or having been scanned for the SIMBAD bibliography is impressive.</p> <p>This list includes a number of additional publications, including colloquia and symposia which are scanned or have been scanned, but not in a systematic way.</p> <p>Only a limited number of journals and periodicals (including all major reference journals, such as <code>A&A</code>, <code>MNRAS</code>, <code>AJ</code>, <code>ApJ</code>) are currently systematically processed, due to the dramatic increase in the total number of publications, and the limited CDS manpower.</p> </li> </ul> <blockquote class="info"><p>If you feel that a paper is missing due to an error in the processing, you can <a href="mailto:cds-question@unistra.fr">contact us by email</a>.</p> <p>You can also use the <a href="http://cdsannotations.u-strasbg.fr/annotations/last?nb=100"target="_blank" rel="noopener">CDS annotations service</a> to add an annotation to a SIMBAD object.</p> </blockquote> </details> <details id="d2975334026"> <summary> How do I report an error in the contents of SIMBAD? <a href="#d2975334026" class="quick-link" title="Quick link on this block."></a> </summary> <blockquote class="info"><p>All the remarks received from the users are very welcome, as they help us to improve the database contents through the scrutiny of specialists' eyes.</p> </blockquote> <p>The data contained in SIMBAD are permanently updated, as a result of errata, remarks from the librarians (during the scanning of the literature), quality controls, or special efforts from the CDS team to better cover some specific domains (e.g., multiwavelength emitters and complex objects).</p> <p>Requests for corrections, errata, or suggestions are regularly received from SIMBAD users through a <a href="mailto:cds-question@unistra.fr">dedicated e-mail address</a>.</p> <p>Corrections of errors are made under the responsibility of CDS astronomers coordinated by C茅cile Loup.</p> <blockquote class="info"><p>You can also use the <a href="http://cdsannotations.u-strasbg.fr/annotations/last?nb=100"target="_blank" rel="noopener">CDS annotations service</a> to add an annotation to a SIMBAD object and share remarks with the community. Each object result page contains a link at the bottom to <strong>"report an error concerning the data of this object"</strong>, and send a notification to the SIMBAD team.</p> </blockquote> </details> <details id="d3113575288"> <summary> How do I check the status of a paper in SIMBAD? <a href="#d3113575288" class="quick-link" title="Quick link on this block."></a> </summary> <p>You can use the paper bibcode or DOI in the <a href="https://simbad.cds.unistra.fr/simbad/sim-fref"target="_blank" rel="noopener">SIMBAD reference query form</a> to find its status.</p> <p>You can then check the meaning of the <a href="https://simbad.cds.unistra.fr/Files/Status.pdf"target="_blank" rel="noopener">status of your paper</a> in the following document summarizing <a href="https://simbad.cds.unistra.fr/Files/Status.pdf"target="_blank" rel="noopener">how we process your article at CDS</a>.</p> </details> <details id="d1745931696"> <summary> Why is this object missing in SIMBAD? <a href="#d1745931696" class="quick-link" title="Quick link on this block."></a> </summary> <p>SIMBAD only contains 20,150,130 objects. This is a small number compared to large catalogues such as <a href="http://vizier.cds.unistra.fr/viz-bin/VizieR?-source=II/246"target="_blank" rel="noopener">2MASS</a>, <a href="http://vizier.cds.unistra.fr/viz-bin/VizieR?-source=V/154"target="_blank" rel="noopener">SDSS</a>, or <a href="http://vizier.cds.unistra.fr/viz-bin/VizieR?-source=I/355"target="_blank" rel="noopener">Gaia DR3</a>, containing in the 10^8 or 10^9 objects.</p> <p>The explanation lies in the very nature of SIMBAD :</p> <ul> <li> <p>SIMBAD is a <strong>meta-compilation</strong> built from what is published <strong>in the literature</strong>, and from our expertise on cross-identifications. By construction it is highly inhomogeneous as data come from any kind of instruments at all wavelengths with any resolution and astrometry, and different names from one publication to another.</p> </li> <li> <p>SIMBAD is not a catalogue, and should not be used as a catalogue. The CDS also provides the <a href="https://vizier.cds.unistra.fr"target="_blank" rel="noopener">VizieR</a> database which contains published lists of objects, as well as most very large surveys.</p> </li> <li> <p>In the past, catalogues like <code>1RXS</code> or <code>IRAS</code> have been enterely put in Simbad, but we do not do that anymore, because the number of objects is increasing exponentially, and because usually only a small percentage of a whole catalogue is actually studied in the literature. We do not want to put all SDSS or 2MASS objects in SIMBAD because <em>SIMBAD focuses on the objects of interest</em>.</p> </li> </ul> <p>We therefore do not systematically process all the catalogues in SIMBAD, and SIMBAD will not contain all astronomical sources ever detected in the sky. But you can use both <a href="https://simbad.cds.unistra.fr"target="_blank" rel="noopener">SIMBAD</a> and <a href="https://vizier.cds.unistra.fr"target="_blank" rel="noopener">VizieR</a> (containing published lists of objects, as well as most very large surveys) as complementary research tools.</p> <p>You can find <a href="http://simbad.cds.unistra.fr/guide/catalogues.htx"target="_blank" rel="noopener">more details on catalogues processing in SIMBAD</a>.</p> </details> <h1 id="usage-of-simbad">Usage of SIMBAD <a href="#usage-of-simbad" class="quick-link" title="Quick link on this section."></a></h1> <details id="d3888793257"> <summary> Where can I have a list of all object types used in Simbad? <a href="#d3888793257" class="quick-link" title="Quick link on this block."></a> </summary> <p>You can see all object types and their relations in the <a href="https://simbad.cds.unistra.fr/guide/otypes"target="_blank" rel="noopener">SIMBAD otypes page</a>.</p> <p>You can change the output (top left) to visualise them in a tabular or hierarchical view.</p> </details> <details id="d1532369617"> <summary> How to cite the usage of SIMBAD? <a href="#d1532369617" class="quick-link" title="Quick link on this block."></a> </summary> See <a href="https://cds.unistra.fr/help/acknowledgement/">how to acknowledge SIMBAD usage?</a> </details> <details id="d3863440539"> <summary> How to group/sort a list of objects according to the spectral type ? <a href="#d3863440539" class="quick-link" title="Quick link on this block."></a> </summary> First, in the <a href="http://simbad.cds.unistra.fr/simbad/sim-fout"target="_blank" rel="noopener">Output Options</a> (yellow link at the top of the SIMBAD query page), you should check the <code>Spectral type</code> for <code>list display</code>. Then, you can click on the arrow in the head of the table, in the spectral type column, to sort the result. </details> <details id="d4252856355"> <summary> How can I see the distance of a list of objects? <a href="#d4252856355" class="quick-link" title="Quick link on this block."></a> </summary> <p>In the <a href="http://simbad.cds.unistra.fr/simbad/sim-fout"target="_blank" rel="noopener">Output Options</a> (yellow link at the top of the SIMBAD query page) you can check the <strong>Measurements</strong> box for a <code>list display</code> (second column) and choose:</p> <ul> <li><strong>catalog list:</strong> <code>Distance</code></li> <li><strong>display</strong> <code>first measurement</code></li> </ul> <p><img alt="Output options for distance in list results" src="https://cds.unistra.fr/help/faq/simbad/simbad_output_distance.png"></p> </details> <h1 id="scripts">Scripts <a href="#scripts" class="quick-link" title="Quick link on this section."></a></h1> <details id="d3349066167"> <summary> Why is my IP blacklisted? <a href="#d3349066167" class="quick-link" title="Quick link on this block."></a> </summary> <p>If you can't access SIMBAD, your computer's IP address might have been blacklisted.</p> <p>In order to prevent abuse, the number of SIMBAD queries is <strong>limited to 10 queries per second from a single IP address</strong>. Exceeding this limit will result in the following restrictions :</p> <ul> <li>If more than 10 queries are received in one second from the same IP address, this IP gets banned for 1 minute.</li> <li>If more than 400 queries are received in 10 seconds from the same IP address, this IP gets banned for 1 hour.</li> </ul> <p>This temporary blacklisting is automatic. You might try the following solutions to avoid the problem :</p> <ul> <li>Add a delay between queries if you are using a script, e.g. <code>time.sleep(300)</code></li> <li>Avoid querying too many individual SIMBAD objects. There are better <strong>dedicated methods to query SIMBAD for a list of objects</strong> : <ul> <li>Use the <A HREF="http://simbad.cds.unistra.fr/simbad/sim-fid" target="_top">Query a list of identifiers</A> section of the SIMBAD query page.</li> <li>Upload your list of targets to the <a href="http://simbad.cds.unistra.fr/simbad/sim-tap"target="_blank" rel="noopener">SIMBAD TAP interface</a>.</li> <li>Use the <a href="http://cdsxmatch.u-strasbg.fr">CDS cross-match service</a> , and choose to cross-match SIMBAD against another catalogue.</li> </ul> </li> </ul> <blockquote class="warning"><p>If you are accessing the web from behind a firewall, you might be sharing the same IP address with other users in your local network.</p> <p>These users might be responsible for the ban !</p> </blockquote> <p>If none of these help, you can <a href="https://cds.unistra.fr/about/contact">contact us</a>.</p> </details> <details id="d1560419855"> <summary> Can I query Simbad with Python? <a href="#d1560419855" class="quick-link" title="Quick link on this block."></a> </summary> You can use the <a href="https://astroquery.readthedocs.io/en/latest/simbad/simbad.html"target="_blank" rel="noopener"><code>astroquery.simbad</code></a> module to query Simbad in many different ways. </details> </main> </div> <div class="void-wrapper for-footer" data-pagefind-ignore>  <footer class="cds-footer for-cds" data-pagefind-ignore> <div class="cds">  <a class="cds logo" href="https://cds.unistra.fr" title="CDS - Centre de Donn茅es astronomiques de Strasbourg" target="_blank"></a>  <div class="socials"> <a class="email" title="Send an email to the CDS team." href="mailto:cds-question@unistra.fr?Subject=CDS"></a> <a class="rss" title="RSS Feed of the CDS news" href="https://cds.unistra.fr/news/rss.php" target="_blank" rel="noopener noreferrer"></a> <a class="facebook" title="CDS' Facebook page." href="https://www.facebook.com/CDSportal/" target="_blank" rel="noopener noreferrer"></a> <a class="youtube" title="CDS' Youtube channel." href="https://www.youtube.com/@CDSportal" target="_blank" rel="noopener noreferrer"></a> <a class="github" title="CDS' GitHub page." href="https://github.com/cds-astro" target="_blank" rel="noopener noreferrer"></a> </div> </div> <div class="service"> <div class="content"> <a class="logo affiliation cnrs" href="https://www.cnrs.fr/en" title="CNRS - Centre National de la Recherche Scientifique" target="_blank"></a><a class="logo affiliation unistra" href="https://www.unistra.fr/" title="Unistra - Universit茅 de Strasbourg" target="_blank"></a><a class="logo affiliation obas" href="https://astro.unistra.fr" title="Observatoire astronomique de Strasbourg" target="_blank"></a> </div> </div> <div class="legal-links"> <a href="https://cds.unistra.fr/about/contact/">Contact</a> - <a href="https://cds.unistra.fr/legals/">Legals</a> </div> </footer> </div> <script type="text/javascript" src="https://cds.unistra.fr/js/cds-general.min.js"></script> </body> </html>

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