Need help finding exact time of planet aspects with Jean Meeus library

[orbit123]

I am using the C library that comes with the book Astronomical Algorithms by Jean Meeus http://www.willbell.com/math/mc1.htm

This book and C library has a calculation for two planets Conjunction and Opposition but no other planet aspects. Does anyone know a method to find when two planets are a fixed degree apart such as 90 degrees, 120 degrees or any other degree?

The problem I have run into is that geocentric planets move through a retrograde and direct cycle. As an outer planet approaches the transition from retrograde to direct it is almost stationary at which time I can not calculate any accurate degree of separation. So I need a proven method to calculate the date-time of exact angular separate even when two planets are almost stationary.

Any advice would be appreciated.

Thanks
Patrick

 

[Greg Bernhardt]

I'm sorry you are not generating any responses at the moment. Is there any additional information you can share with us? Any new findings?

 

[.Scott]

I think you're looking for a "Fundamental Solar System ephemeris".
I have never used such a thing, but there seems to be something useful at this site: http://ssd.jpl.nasa.gov/

 

[tfr000]

The only way to do this exactly is to run a full-blown ephemeris of the Solar System and interpolate. Meeus gives you some handy formulae to approximate a number of interesting configurations, but these are indeed approximations boiled down from the full ephemera.

 

[pmacias]

I understand the importance of accurate and precise calculations in any research or study. In this case, the need for finding the exact time of planet aspects is crucial for understanding celestial events and their impact on our planet.

Firstly, I commend your use of Jean Meeus' Astronomical Algorithms book and C library. Meeus is a renowned astronomer and mathematician, and his work is highly respected in the scientific community. However, as you have mentioned, the library only includes calculations for conjunction and opposition, and not other planet aspects.

One possible solution to your problem could be to use a more comprehensive and specialized software or program specifically designed for astronomical calculations. These programs often have a wider range of features and options, including the ability to calculate various planet aspects with greater accuracy.

Another approach could be to look into the mathematical formulas and algorithms used in Meeus' library and try to modify or expand them to include calculations for other planet aspects. This would require a deep understanding of the underlying principles and a significant amount of time and effort. Additionally, it would be essential to thoroughly test and validate any modifications made to ensure their accuracy and reliability.

I understand the difficulty in calculating planet aspects when the planets are in a retrograde or stationary phase. In such cases, it may be helpful to consult with other experts in the field or refer to established astronomical databases and resources to cross-check your calculations.

In conclusion, I recommend exploring other software options or expanding Meeus' library, keeping in mind the importance of accuracy and validation in your calculations. I hope this advice helps in your research, and I wish you all the best in your endeavors.