Willman observing, ACS WCS

We got some good and some mediocre data for Beth last night; tonight is cloudy so we are working other things, particularly Morad's small-scale clustering paper.

Here is a comparison of an HST ACS image with the USNO stars in the field, after I have applied my WCS-fixing code. Note that many of the USNO "stars" are not stars at all:

(Image made with "astrometry/pro/hogg/hogg_acs_wcs.pro")