I haven’t shared much about software in the Public Domain, but tonight I found a terrific program that might be worth your attention, especially if you’re interested in Astronomy (as I am).
Release 3.3a of Home Planet, a comprehensive astronomy / space / satellite-tracking package for Microsoft Windows 95/98/Me and Windows NT 4.0/2000/XP and above, is now available. Home Planet is in the public domain; it is free software. It allows you to view:
- An earth map, showing day and night regions, location of the Moon and current phase, and position of a selected earth satellite. Earth maps can be customised and extended by editing a DLL which provides maps to Home Planet.
- A panel showing detailed position and phase data for the Sun and Moon.
- Panel showing positions of planets and a selected asteroid or comet, both geocentric and from the observer’s location.
A sky map, based on either the Yale Bright Star Catalogue or the 256,000 star SAO catalogue, including rendering of spectral types, planets, earth satellites, asteroids and comets. Celestial coordinates are included, and an extensive and user-extensible deep-sky database includes all Messier objects and many of the NGC objects. Precession and proper motion are accounted for in the display.
- Databases of the orbital elements of 5632 asteroids and principal periodic comets are included, allowing selection of any for tracking. These databases can be user-extended using standard orbital elements. MS-DOS utility programs are included which convert asteroid and comet orbital elements in the form published in Minor Planet Electronic Circulars (MPECs) to the CSV format used by Home Planet. Subscribers to the MPECs can thus easily add newly reported asteroids and comets to the database. Source code for these programs is included.
- A telescope window which can be aimed by clicking in the sky map or telescope itself, by entering coordinates, or by selecting an object in the Object Catalogue (see below). Limiting magnitude, labeling, coordinate display, etc. can be defined by user. Right click on an object to display its entry in the Object Catalogue. Stellar magnitudes can be plotted for stars in a given magnitude range in the telescope window. This makes it easy to create comparison star charts for variable star observing.
- A horizon window which shows the view toward the horizon at any given azimuth. The horizon can be adorned, if you wish, with fractal forged terrain and randomly generated scenery, including houses, livestock, and trees. The scenery is generated by a user-extensible DLL which allows customisation.
- Object Catalogue allows archiving images, sounds, and tabular data about celestial objects. Both new objects and new categories can be added. Bidirectionally linked to the Telescope window.
- And a lot more!
The programmer has also included the source code on the download page should you want to develop the program further. You can download a copy of this great software at: http://www.fourmilab.ch/homeplanet/