These CMOD billboard objects were created by Selden Ball either manually or using specialized programs written in Fortran. No 3D modelling programs were used.
The "Carina" image used with the billboards above were derived from pictures published on the Web at
http://hubblesite.org/newscenter/archive/2000/06/. Credit for the original images goes to NASA and the Hubble Heritage Team ( AURA / STScI).
The texture for NGC 3372 was derived from the image 02192.TIFF, available at
http://www.noao.edu/image_gallery/html/im0061.html. The credit for this picture goes to "National Optical Astronomy Observatory/ Association of Universities for Research in Astronomy/ National Science Foundation." According to the NOAO copyright page at
http://www.noao.edu/image_gallery/copyright.html, their images may be used freely for "educational outreach activities composed by amateur astronomers". That's what this is.