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

  • #1
Philosophaie
462
0
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?
 

Answers and Replies

  • #2
18,954
9,273
Thanks for the post! This is an automated courtesy bump. Sorry you aren't generating responses at the moment. Do you have any further information, come to any new conclusions or is it possible to reword the post?
 
  • #3
jim mcnamara
Mentor
4,702
3,653
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.
 
  • Like
Likes Philosophaie

Suggested for: Convert to "Of Date" Apparent coordinates from "J2000" coordinates

  • Last Post
Replies
6
Views
148
Replies
0
Views
842
Replies
15
Views
897
  • Last Post
Replies
2
Views
932
Replies
8
Views
962
  • Last Post
Replies
3
Views
1K
Replies
2
Views
1K
  • Last Post
Replies
4
Views
2K
Top