ADD (Ver 5) Siderral Calculation

[calvin.harman@…]

Equations 45 and 46 of the ADD look the same, however after reading the
descriptions before each, it seems that the JD member of each equation is taken
relative to a different time frame. Can a subscript be added to the JD member
in each equation for clarification?

Also, as a sanity check...The denominator in these equations is given as 36525.
Should this be 365.25 (as in 365 days in a year), or is this just a coincidence?

[Paul Price]

Yes, the JDs are for TDT and UT1, i.e., TDT and UT1 expressed as Julian Dates.
I've added subscripts in the ADD:

t_u = \frac{{\rm JD}_{\rm TDT} - 2451545.0}{36525}
t = \frac{{\rm JD}_{\rm UT1} - 2451545.0}{36525}

The denominators are truly 36525, so that the output is "Julian centuries".

[Paul Price]

Should be fixed in SDRS-07 and ADD-06 (7 September 2004).