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.
The Aladin stack shows all elements that have been loaded during your Aladin Desktop session. The stack is a pile of individual planes, which can be pointed images, HiPS surveys, catalogues, graphical overlays, filters, data cubes, etc...
Each time you load a new element, a new plane will be added to the stack, usually at the top. To understand what is displayed in the main Aladin panel, imagine you are looking through the stack, from the top :you see all elements overlaid on top of each other, until you reach an opaque plane (in this case the DSS HiPS survey).
Clicking on the trapezium icon at the left of a plane allows you to toggle it off, or back on ; this can reveal planes below it.
Clicking on the name of a plane makes it the active plane in the stack. It is highlighted, and buttons such as « Properties » will apply to this active plane.
If you want to delete a plane from the stack, make sure to select it, and click the delete button. You can select several planes by pressing the CTRL or Shift keys while selecting them, and delete them at once.