mosaicing, HST, source detection

Worked on the code to mosaic together the KPNO Mosaic data into huge images (and pretty pictures).

Discussed with Phil Marshall, Lexi Moustakas, Chris Fassnacht, et al. the issues involved in setting up our duplicate of the HST Archive, which will have special functionality for those who are doing survey science. Much of the discussion centered around what form of the data to store/serve. The raw bits—for the entire HST lifetime—add up to only 1.7 Tb or something in that ballpark. The reduced data are more than ten times larger (more numerous?). Phil posted the minutes here.

In the context of this discussion, we discussed briefly the issue of working on/with stacked images. Everyone is in more-or-less agreement that it is possible—in principle—to do all image measurements (including photometry, profile fitting, etc., but especially faint source detection) on the individual, unstacked frames; working on the stack can only be same or—more likely—worse. The problem is that in practice there are no good codes available. Perhaps this collaboration will create some.

In the short term, however, the project is science-oriented and just-in-time, in the extreme coding model, so we won't write any such code until we need it.