AstroMosaic is a small commandline program to help the creation of a mosaic (a big image that is a collection of smaller images). It can automatically find the best aligment of the images. Its main goal was to compose astronomical images from a Webcam. It can take any image format supported by Qt as input.
Sunwait is a small program for calculating sunrise, sunset, civil twilight, nautical twilight, and astronomical twilight. It has options to wait until some time-offset from one of these events, making it useful for home automation tasks that should happen relative to the sun's position.
PAPFIP (Python And PGPLOT-based FITS Image Plotter) is a FITS image plotter based on the Python bindings to the pgplot graphics library. It is intended as a non-interactive (command line or script-driven) astronomical image plotter intended for the automated or repeated production of finalized publication-quality Postscipt files, rather than a method of inspecting or visualizing the data.
Astro::DSS Module is an object orientated Perl module that provides an interface to both the first and second Digital Sky Surveys at the ESO-ECF online archive. While the first sky survey is 100% complete, the second survey covers 98% of the sky in Red, 45% of the sky in Blue, and 27% of the sky in Infra-red.
libAstronomy provides a set of astronomical routines to ease the calculation of ephemerides. It includes mathematical functions to compensate various astronomical phenomena like precession, nutation, etc. The getconstellation routine finds the constellation for a given coordinate. It also calculates the positions of the sun and moon in two different precise ways.
ImageJ is an image processing program inspired by NIH Image for the Macintosh. It can display, edit, analyze, process, save, and print 8-bit, 16-bit, and 32-bit images. There are modules for biology, astronomy, nuclear medicine, physics, and more. If you can take a picture of something, whether with a microscope, a telescope, an oscilloscope, an xray machine, or a scanner, then this program will let you enhance, manipulate, and measure the results.