If you click on the appropriate link below (*) you will be able
to download a zip file which contains:
the program SKY-SPROG, as an exec. file which will run
on any PC
An associated data file called SKYBADA.
In addition you will find a text file which gives the
program's listing. This text listing can be pasted into BB4W in the usual
way so that it can be saved as a .bbc file and subsequently MODIFIED to
do what you want it to do - its not set in aspic.
SKY-SPROG Planetarium Program contains all
you need for many astronomical situations.
This tiny program was originally distributed on a tape cassette and it
was shoe-horned into the limited memory of the BBC Model B. Now with no
such limitations it can be developed into whatever you like. Its operation
needs quite a few key presses as it stands but I leave it to you to "mousefy"
it if you can do it before I do.You can set the observers position for any
latitude and longitude. The default is set for London.
The author of the original program (written for the BBC Model B
computer) now wishes to remain anonymous and does not wish to take any further
part in its development. He generously gives it to us to make of it what
we will. Many thanks to him! The only changes I have made so far
from the original are:
to use the PCs internal clock so that the program starts up at
the present time and date
to read the data file positions of the stars automatically on startup
to put instructions on the opening page to facilitate navigation
- please be sure to read these carefully and possibly note them down, or
print out this web page.
Essentially, you need to remember to press the Space Bar twice
to return from a sky view to the main menu.
To identify the stars, planets etc you use the arrow keys to bring
the Space Probe over the lower left hand side of the object.
You can change the view : N, E ,S, W and NE etc, and also get a
Don't forget that after choosing to search for (say) a planet and
(say) choosing Jupiter and (say) to see it at culmination time, you still
need to press the space bar and then display the section of
the sky! (Quite a few users have emailed about navigating this bit of the
To unzip the SKY-SPROG.zip file use WINZIP or POWERDESK or some
The great thing about this program is that it is beautifully and
economically written in BBC Basic, which you can modify and mine for
its incredibly useful functions.(See the example "Ecliptic, Sun, Moon,
Planets program" in the demonstration programs for an example of a program
which makes use of Basic Procedures from Sky-Sprog). The original author,
a Cambridge mathematician, wrote it in his retirement from scratch using
standard astronomy texts.