Greg Neill wrote:
W. eWatson wrote:
I have the fourth edition of Meeus (1988?) and haven't used it for quite
awhile. I just discovered a similar book by Duffett-Smith that may
pre-date Meeus. What's the difference between the two?

Which books precisely are you referring to? Both Meeus and
Duffet-Smith did books targeted for hand calculators and
more general purpose methods that are suitable for computer
implementation.

Duffett-Smith:
- Practical Astronomy With Your Calculator
- Astronomy With Your Personal Computer

Meeus:
- Astronomical Formulae for Calculators
- Astronomical Algorithms

Duffet-Smith's computer book contains a lot of BASIC program
listings, which may or may not be of use to you. Meeus' book
has a disk available containing the data and programs, but the
methods in the book are presented in mathematical form that is
not just pidgin BASIC.


Practical Astronomy With Your Calculator, 2nd ed. Never heard of it
until last week. I'm using a library based on their work. I suspect that
it may be used because the copyright expired, or they really had no
objection to others using it.

Astronomical Formulae for Calculators, 4th ed. I have it.

I wonder what the pros use, if not these? I suspect some of the better
math libraries are involved in any case.

I'll stick with Duffett-Smith. In any case, Meeus is helpful checking
what I'm doing with the library and providing a reference for what's
really happening. The library has virtually no introductory material.
Maybe Duffett-Smith provides the background.