not sure if this is the right forum to ask my questions but it does relate to my observations of eclipsing binaries. I am aware of several websites where Julian dates can be entered from which Heliocentric Julian Dates are then calculated but I want to do the calculation in a my own Excel spreadsheet.
Can anyone provide the relevant equations? The only input parameters as far as I can see would be JD and the object's RA and Dec.
Any advice would be much appreciated. Cheers,
These two links should help:
You'll need the second link to compute the RA and DEC of the sun.
I've used Lew Cook's spreadsheets, very useful but the details of calculations are hidden. I was contacted off-line by a colleague who provided his spreadsheet based on info in Astronomical Algorithms by Jean Meeus, so I think I have what I've been looking for. Cheers,