Undergrad Convert to "Of Date" Apparent coordinates from "J2000" coordinates

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To convert "J2000" coordinates to "Of Date" or "Apparent" coordinates, users can utilize resources like the JPL Horizons system, which offers both coordinate types, or Stellarium software, which displays both formats. There is no straightforward formula provided for the conversion, and the approach may depend on the user's programming skills, with suggestions for using languages like C or FORTRAN. Additionally, Jan Meeus's books on astronomy are recommended as valuable resources for amateurs seeking to understand these conversions. The discussion also touches on the potential need for future orbit projections of Solar System objects. Overall, the conversation emphasizes the importance of using specialized software or programming for accurate conversions.
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How do you convert to "Of Date" or "Apparent" coordinates from "J2000" coordinates?

The website:
http://ssd.jpl.nasa.gov/horizons.cgi#results
there are two options for displaying RA and DEC: Astrometric and Apparent. Astrometric is the J2000 coordinates and Apparent is the "Of Date".

http://www.ephemeris.com/goto.php
Just lists the Apparent

www.stellarium.org software
Lists both "Of Date" and J2000 coordinates.

My question is: Is there a formula to convert between the two coordinate systems?
 
Short answer - what are you trying to do? Can you write programs in some language like maybe C or FORTRAN?
I suppose you can use a sophisticated programmable TI calculator...
@D H probably can help with a lot more detail - the JPL has software that does astronomical calculations. And copes with Jxxxx. AFAIK.

Jan Meeus has several books meant for amateur astronomers. Please consider one of them as a great starting point.
Exmple: https://www.amazon.com/dp/0943396352/?tag=pfamazon01-20

As an aside - are you trying to project orbits of Solar System objects into the future? All of what I did was always okay with existing ephemera.
 
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