LinuxAstro - Astronomical software on Linux. Nightfall - Interactive program for computing synthetic lightcurves and generating animated views and best-fit models of eclipsing binary stars. [Open source - Linux/Unix] Image Reduction and Analysis Facility (IRAF) - A software system for the reduction and analysis of astronomical data. Linux for Astronomy cdrom - Astronomical software precompiled for the Linux operating system. Applications include general purpose image and signal processing tools, as well as algorithms in use at observatories and universities worldwide. Facilities for processing the data products of the major space-based instruments are also included. [Commercial - Linux] 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. Deepsky 2000 - Observation planning software for astronomers. Includes telescope control, logging, and charting.[Commercial - Windows] Astronomy Common Object Model (ASCOM) - Promoting the use of open scriptable tools for amateur and educational astronomy. 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. Orrery - Review of the solar system simulator (by Spacetech) for RISC OS workstations. 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. Astronomy Software Resources - Discover links and resources for astronomy software for amateur and professional astronomers and for people interested in astronomy, stargazing and space. AstroMB - Advanced software for astrometry, photometry, robotic observations. Huge database of images and catalogs. Works with MaximDL and ASCOM. Free downloads. Alcyone Software - Features the following programs: an ephemeris calculator, a collection of astronomical data in electronic form, Planet Orbits, C88, and Planetary, Lunar, and Stellar Visibility. Observation Manager - Free and open java based astronomical logging tool. It stores data in an XML format called COMAST, a tool which provides a free schema definition for all kinds of astronomical observations. DanIDL - Provides a library of functions and routines written in the Interactive Data Language (IDL). Developed mainly for use in astronomy, the library also supplies general scientific and programming applications. 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. 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. Distro Astro - Linux-based operating system for astronomers. Astropy - A community Python library for astronomy. ShiningStar Software - This is a digital sky map software which demonstrate the universe in solar space mode, equator mode, and horizon mode. You can view the whole solar system, look at any of the planets nearly, see the whole sky as standing at anywhere on the earth. Instrument Neutral Distributed Interface (INDI) - The INDI library provides a framework for control and automation of astronomical instruments. Caglow Central - A free project repository for [semi-]open astronomical software.