The Julian day for this
DateTime at the given time. For example, prior to noon,
1996-03-31 would be the Julian day number 2_450_173, so this function
returns 2_450_173, while from noon onward, the julian day number would
be 2_450_174, so this function returns 2_450_174.
The Julian day for this DateTime at the given time. For example, prior to noon, 1996-03-31 would be the Julian day number 2_450_173, so this function returns 2_450_173, while from noon onward, the julian day number would be 2_450_174, so this function returns 2_450_174.