Using Aladin with APT in Phase I

Aladin is the tool for visualizing observations in APT. Aladin requires apertures to work, and since those are not part of the normal Phase I submission, you need to add this information. For a demonstration using a specific example, see the training movie.

At the bottom of the Observation form is an area for Aladin inputs.



The first item is a picklist for the Detector, and is based on the Instrument Setup (it defaults to the first detector you specified). The second item is a picklist for the Aperture, and is based on the Detector selected. Note that not all possible apertures are available in order to keep Phase I as simple as possible (all apertures are available in Phase II). The next items are used to link any coordinated parallel observations to the prime observation. Note that if an Observation is defined as a coordinate parallel (by selecting the Coordinated Parallel flag), then these fields, as well as the mosaic fields, are not available for that Observation (since the Prime Observation controls the Parallel). The next 2 items, as well as the Add Tile button, are for mosaics only, and are described in that help.

The Aladin Orientation Angle is the aperture orientation shown in the Aladin display. If we had specified an ORIENT range for the observation, this value would be initialized to the midpoint of the range. Since we have not specified an ORIENT, it defaults to 0. Note that this value is strictly a display value.

If you open the Observation containter, you will see a Mosaic Tiles folder, which contains Tiles. For non-mosaic observations, there is only 1 tile.



The POS TARG X and Y fields give the offsets for mosaic tiles (and are not present for non-mosaic observations), while the Aperture Color allows you to change the plotted color of the aperture.

Select the View in Aladin tool, which brings up the Aladin window.



To load a DSS (or other image, such as Hubble Legacy Archive footprints) image into Aladin, use either the File Menu or the Server Selector, and enter the appropriate information.



Note that you will need to move the Observation folder in the Aladin Tree to be above the DSS image.



Note that the Aladin apertures are semi-transparent. If you want to adjust the transparency, then under the Edit menu/ User preferences, you can adjust, or turn off, the opacity; you will see the change after hitting the apply button.



You can change the sizes of the various regions of the Aladin window by grabbing the edge of the region and adjusting the size. You can change the image scale (Zoom) by either using the Zoom pull-down menu, or by select the Zoom function in the option bar; for the latter case, a left click increases the magnification, while shift-left click decreases the magnification. You can pan around the image by selecting the Pan function in the option bar.

If you wish to change the orientation of the aperture, grab the corner of the aperture (make sure you have the cursor) and move the cursor. If you go back to the Observation in APT, you will see that the Aladin Orientation Angle value has changed. If you want to use this Orientation for your observation, you will need to go back to the Scheduling Requirements area of the Observation and input your desired range.

If you wish to adjust the pointing, grab the aperture (make sure you have the cursor) and move it to the desired position. Note that any changes you make graphically will be reflected in the APT window. You can then decide to commit the changes to your proposal or clear them.


To investigate the utility of a coordinate parallel observation, select the FOV option in the APT window. You can rotate the primary aperture to place any object of interest in a parallel aperture.



If you already have a coordinated parallel observation specified in your proposal (by selecting the Coordinate Parallel flag on the Observation and linking the Parallel to the Prime), you can display both observations by selecting both in the APT Tree Editor.



You can also overlay catalogs on the image. Click on the File/Load Catalog (or use the Server Selector or the quick load), and select the desired catalog (e.g. SIMBAD) and submit the catalog query.



You can get information on the objects in the catalog by placing your cursor on the object and clicking - information from the catalog will be displayed in the mini-spreadsheet at the bottom of the Aladin window; the spreadsheet is closed by default, but will open automatically when you select an object. Note that if you have multiple catalogs displayed, and an object appears in both, clicking on that object will display the information from all catalogs. Note that if you have 2 different catalogs for a single objects, the columns shown in the Aladin data area are appropriate for the first catalog listed. However, if you put your cursor in a column for the second catalog, you can see the correct column headers.



If you want to save a copy of the image for inclusion in your PDF attachment, select the Save option in Aladin. The Save Current View will save the image in a format that can be used in your PDF attachment.




Last modified: December 18, 2012.