The software program which
shows planetary positions is
for sale for $60.
It is very flexible and easy to use. Anytime within 10,000 years in the
past and 10,000 years in the future can be examined.
At the click of a mouse, geocentric and heliocentric degrees are displayed.
It comes with a text explaining how Solar Activity is predicted. One
geophysicist, Rhodes Fairbridge, said it was better and easier to use than his
more expensive astronomical programs.