SetiContainer is a C++ class that allows convenient access to all the information in the state files of a SETI@home client. It periodically examines these files and updates its own data members accordingly. Other programs can use this class to extract information about the progress of the client, the found signals, or the work unit being processed. Additional functions offer more advanced info (like the amount of TeraFlops in a work unit, estimated time of completion, etc.). The SetiContainer class is based on the Qt toolkit, and extensively uses Qt's Signal/Slot technique.
x10ephem computes sunrise and sunset times. It consists of a library and an assortment of utilities. The most useful utility is x10events, which parses crontab files and updates the time fields to track sun events. Combined with an X10 interface like HEYU or X10, this allows the scheduling of lighting events to follow the changing seasons and daylight savings time automatically. This application does not depend on X10; it can be used for any crontab entry you like.
Xplanet was inspired by Xearth, which renders an image of the earth into the X root window. All of the major planets and most satellites can be drawn, similar to JPL's Solar System Simulator. A number of different map projections are also supported, including azimuthal, Mercator, Mollweide, orthographic, and rectangular.
StarPlot is a GTK-based program, written in C++, which can be used interactively to view three-dimensional perspective charts of stars. Charts can be recentered, rotated, or zoomed in or out with a mouse click (this can also, of course, be done via dialog boxes for more precision). Stars may be viewed (or ignored) by spectral class and absolute magnitude. Other features include support for both celestial and galactic coordinate systems, the ability to display extended non-stellar objects, and a pop-up Hertzsprung-Russell diagram. StarPlot is also packaged with starconvert, a utility which converts line-oriented stellar data records to StarPlot format. Most star data files available on the Internet can be converted this way if a short file describing the original file format is provided to starconvert.
Nova is a free Integrated Observational Environment for astronomers. It combines Ephemeris functionality with the capability of controlling modern "goto" telescopes and popular CCD cameras. Nova combines image capture, telescope control and ephemeris functionality into a single application. The main goal of Nova is to make it easy(ish) to capture CCD images of objects with a good degree of accuracy. Nova is also able to manage several kinds of astronomical database (i.e GSC, USNO, SAO, etc.) and makes it easy to automatically schedule observational activity through the use of target object lists.