Centre de données astronomiques de Strasbourg
The Strasbourg astronomical data center (CDS) provides reference astronomical services:
- SIMBAD is the reference database for identification and bibliography of astronomical objects (outside the solar system).
- VizieR is a catalogue service for large sky surveys, catalogues and tables published in academic papers, and more and more other data associated to publications.
- The interactive sky atlas Aladin provides an interactive portal to access image collections and databases available via Virtual Observatory protocols.
- The CDS cross-match service allows to do positional cross-matching of very large catalogues.
We introduced in another tutorial the Aladin desktop data collections tree, and we will now demonstrate advanced available features.
- First of all, you can rearrange or sort the tree in different ways: using the "Sort" button at the bottom, you can rearrange the tree for example by wavelength domain, or by publication year.
- The sorting can be applied to all leaves under a given node by first selecting it, and using the dedicated sort button.
- There are various icons used for data collections : first an icon identifying the data provider, an RGB icon to quickly distinguish colour compositions from single band images, and a small yellow asterisk to identify new collections.
- The tree can be also filtered by sophisticated advanced rules, clicking on the dedicated button, for example catalogues with proper motions.
- These advanced filters can be named and stored for future usages, in addition to predefined ones.
- For some data collections, the information on spatial coverage is not readily available : they appear in grey, and are identified with a small orange icon. One can use the "scan" button to query if such a service has an overlap with the current field of view or not.
Download Aladin desktop : http://aladin.u-strasbg.fr/java/nph-aladin.pl?frame=downloading