Solar System Live: Credits

Solar System Live was implemented by John Walker in February and March of 1995. The calculation and display software was adapted from Home Planet for Windows. See the details for additional implementation information.

The GIF output file generation is based upon the ppmtogif module of Jef Poskanzer's pbmplus toolkit, of which many other components were used in creating the images you see here.

   ppmtogif.c - read a portable pixmap and produce a GIF file

   Based on GIFENCOD by David Rowley [mgardi@watdscu.waterloo.edu].
   Lempel-Zim compression based on "compress".

   Modified by Marcel Wijkstra [wijkstra@fwi.uva.nl]

   Copyright © 1989 by Jef Poskanzer.

   Permission to use, copy, modify, and distribute this software and its
   documentation for any purpose and without fee is hereby granted, provided
   that the above copyright notice appear in all copies and that both that
   copyright notice and this permission notice appear in supporting
   documentation.  This software is provided "as is" without express or
   implied warranty.

   The Graphics Interchange Format© is the Copyright property of
   CompuServe Incorporated.  GIF(sm) is a Service Mark property of
   CompuServe Incorporated.

Steven Grimm's uncgi made the task of processing form arguments in the server immeasurably easier.

The mechanical orrery shown in the heading of the main page is in the National Air and Space Museum of the Smithsonian Institution in Washington DC in the United States. The image is © Copyright 1993 Smithsonian Institution.

The algorithms to calculate the positions of the Moon, planets, asteroids, and comets are given in:

Meeus, Jean. Astronomical Algorithms . Richmond: Willmann-Bell, 1998. ISBN 0-943396-63-8.