I have this problem: I want to calculate the declination of the star in the year 5000. And I know RA (right ascension) and Dec (declination) of the star right now.
How can I calculate it using spherical trigonometry.
I know that the declination changes over time due to the precession and somewhere I read that I should use spherical triangle, but I am not really sure how to use it.
Thank you for your ideas.