We are entering a great era when it comes to research tools for the study of deep space. But as new technologies create datasets we’re able to distribute globally, we need to consolidate our gains to make them available to broader audiences. That’s why the creation of a Web-based utility called COSMOS SkyWalker is such heartening news. Using it, huge and minutely detailed images from sources like the Hubble Space Telescope’s Advanced Camera for Surveys can be managed for presentations and study over the Internet.
The problem is no small one. Compare the Hubble Ultra Deep Field (UDF), which contains some 10,000 galaxies, to the Cosmological Evolution Survey (COSMOS), housing no less than 2 million. The image areas on these surveys are contiguous and made up of an extraordinary number of data pixels, some 1010 pixels for COSMOS. That kind of scale makes it all but impossible to show both size and detail at the same time. Shipping the complete COSMOS ACS image over the Internet, even in compressed JPEG format, is not feasible, nor are average PCs up to the challenge of displaying such imagery.
Yes, there are dedicated scientific data viewers, but SkyWalker fills a notable gap, being useful for quick access to ACS imagery and especially handy for those of us who occasionally present live material to non-scientific audiences. The COSMOS ACS mosaic is now available on the SkyWalker site, but other datasets are being added. For background on how the software works, check Jahnke, Sanchez and Koekemoer, “Seeing the Sky Through Hubble’s Eye: The COSMOS SkyWalker,” avalable here.