Our first data set originally came from the IRAS point source catalog (PSC). It is a scaled down (by a factor of about 25) version of the original catalog and consists of an ASCII table containing fluxes at a variety of wavelengths as well as the right ascension and declination of the sources in equatorial coordinates. This scaled down version is still rather large, containing over 10000 sources. Therefore, we have subsampled this smaller file by a factor of 20. Because the file consists of ASCII numbers, a format for reading the data must be specified before it is loaded. Once it is loaded, a Table Overlay object can be created, as shown in Fig. 1. Notice that flux amount, represented by the dots, is correlated with both color (red is high) and size (large is high). Symbol type, size and color are selected by the user.

Figure 1.  Overlay tool with color table attached.

Figure 2. An Image application showing a radio image of  the sky in an orthographic projection.

The other data in this example were obtained by using the Skyview WWW tool to select 2 radio images of the sky, both in equatorial coordinates. The 2 images differ in that one (Fig. 2) was requested from the Skyview server in an orthographic projection, and the other in a Hammer-Aitoff projection (Fig. 3). When the server returns the data, it puts both projection and coordinate information in the header of the FITS file. When the WWW browser returns the FITS files to WebWinds, these files appear as data objects and the header information can be used to map the data to the proper coordinate system and projection. In Fig. 2, we see that the IRAS point data have been overlaid on the radio Image. Changes made with the Overlay tool are reflected in this Image, as well as the one shown in Fig. 3. We have also turned on a coarse grid, in Fig. 2., which is automatically drawn in the proper projection.