Hubble Space Telescope -- Wallpaper
[commercial - Win95/98/NT] Thirty full-screen Hubble photos for use as wallpaper and screen saver.
http://www.screenthemes.com/packs/hubb001/showall.htm

Computing planetary positions
a detailed online tutorial on how to compute planetary positions.
http://hotel04.ausys.se/pausch/comp/ppcomp.html

Nightfall
[open source - Linux/Unix] Interactive program for computing synthetic lightcurves and generating animated views and best-fit models of eclipsing binary stars.
http://www.lsw.uni-heidelberg.de/~rwichman/Nightfall.html

Linux for Astronomy cdrom
[commercial - Linux] The new release of Linux for Astronomy includes over 3Gb of Astronomical software precompiled for the Linux (x86) operating system. Applications include a wealth of general purpose image and signal processing tools, as well as the state-of-the-art algorithms in use at observatories and universities worldwide. Facilities for processing the data products of the major space-based instruments (Hubble Space Telescope, EUV, Einstein, ROSAT, and IUE) are also included.
http://www.randomfactory.com/lfa.html

LinuxAstro
Astronomical software on Linux.
http://bima.astro.umd.edu/nemo/linuxastro/

Engineering, Science and Math Applications on Linux
A large indexed collection of pointers to Linux applications.
http://www.xnet.com/~blatura/linapp3.html#science

Astronomy-related software
A list of many astronomy-related programs.
http://www.open.hr/space/space/programs.htm

Kairos General Calendar Conversion Program
[commercial, demo available -- Win95/98/NT] Includes calendars required by historians of astronomy and general historians. Many details are provided for Indian and Jewish calendars and much besides. There is also a display of positions of the Sun, Moon and planets, effectively replacing Tuckerman's tables. A horoscope display, and details of lunar visibility, are calculated from modern parameters.
http://ourworld.compuserve.com/homepages/raymondm

Computing planetary positions
a tutorial with worked examples.
http://hotel04.ausys.se/pausch/comp/tutorial.html

EVCODE
A stellar evolution simulator designed for astronomy education.
http://phastf.phys.uvic.ca/htbin/dir_html?evcode

AstroTips - Astronomy Freeware and Shareware
Information on selected astronomy free software. Read a comment, see a screenshot and download.
http://www.stargazing.net/AstroTips

Ksetiwatch
Ksetiwatch monitors multiple SETI@home clients and automatically logs and manages completed work units.
http://ksetiwatch.sourceforge.net

GeoClock
[shareware MS-W] Sunlight clock with world times and sun and moon positions and coverage.
http://www.geoclock.com/

Cartes du Ciel / Sky Charts
Freeware allowing one to draw charts according to the data of 15 catalogs of stars and nebulae, as well as the position of planets, asteroids, and comets. Available in English and is translated in 8 other languages.
http://www.stargazing.net/astropc/

Deepsky 2000
[commercial - Windows] Observation planning software for astronomers. Includes telescope control, logging, and charting.
http://www.deepsky2000.net/

Astronomy Common Object Model (ASCOM)
Promoting the use of open scriptable tools for amateur and educational astronomy.
http://ascom-standards.org/

RISC OS astronomy software links
freeware - RISC OS] Direct links to astronomy software available for RISC OS.
http://www.harmsy.freeuk.com/resources.html#soft

The Salopian Web
Software links for astronomers professional, education and amateur. Planetaria, sky charts, and databases for PC, MAC and UNIX/LINUX platforms.
http://www.r-clarke.org.uk/astrosoft.htm

Astronomy Formulas
Lunar and solar periodicity formulas, definitions, time formulas, notation, astronomical constants with computer code for a programmable HP 48 by James Q. Jacobs.
http://www.jqjacobs.net/astro/astrofor.html

Orrery
Review of the solar system simulator (by Spacetech) for RISC OS workstations.
http://www.harmsy.freeuk.com/orrer.html

Sky and Telescope -- Astronomical Software
Telescope, to shareware/freeware astronomy related software and to vendors of astronomy software.
http://skyandtelescope.com/resources/software/

Astronomy Explorer
A full-length academic approved course in astronomy on CD-ROM that studies the universe, stars, galaxies, quasi-stellar objects and blacks holes, and our Solar System.
http://www.eoascientific.com/science_education_software/astronomy/astronomy_software.html

AstroMB
Advanced software for astrometry, photometry, robotic observations. Huge database of images and catalogs. Works with MaximDL and ASCOM. Free downloads.
http://www.astromb.com

Approximate Astronomical Positions
Calculations including coordinate conversion, position and circumstances of the Moon, and positions of the planets. Designed for programmable calculators, spreadsheets and illustrative applications where high accuracy is not needed.
http://www.xylem.f2s.com/kepler/

Lunar Calendars and Eclipse Finder
Windows software for converting dates in various lunar and other calendars and for finding lunar phases and eclipses of various kinds.
http://www.hermetic.ch/lcef/lcef.htm

Astronomy Software Resources
Discover links and resources for astronomy software for amateur and professional astronomers and for people interested in astronomy, stargazing and space.
http://space.about.com/cs/software/