Base-N
Convert numbers from one base to another quickly; up to base 36. Includes decimal fractions.
Timex/Sinclair 1000
Celestial Locator
Provides the amateur astronomer with AZ/ALT positions for any given celestial source. Radio astronomers can rapidly adjust antennas with the location positions provided by this program. Can print monthly positions on RS232 printers via ZX99. 16K.
Galaxy
Draws normal and barred spiral galaxies from input parameters. Galaxies may have variable orientation from face-on to edge-on. Choice of two spiral algorithms. 16K.
Multigraphics 2.3
Menu-driven package gives full control of ZX81 graphics. Includes: Comprehensive sketch pad function, small, large and jumbo text functions. Two packages of mixed graphic and text displays or one animated display. Educational/tutorial, business graphics functions for shop-window advertising displays. 16K.
Orbit
Astronomical demonstration program for educators. Draws elliptical orbit shapes based on eccentricity. Also calculates and produces animated display of orbital motion. 16K.
Planetfinder
Computes the right ascension and declination, constellation planet is in v brightness, distance from earth, angular diameter, and phase. For any planet, any date. 16K.
Planets
Calculates and displays positions of the planets around the sun for a date or series of dates. Can plot planet distances to scale and include a comet. 16K.