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Full Version: the IAU 1980 Nutation algorithm
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This HP Prime program demonstrates how to call a subroutine called nutate80. The nutate80 source code implements the classical IAU 1980 nutation theory.

Here's the syntax of the routine.

EXPORT nutate80(jdate)

// nutation in longitude and obliquity

// IAU 1980 version

// input

// jdate = julian date

// output

// vnut(1) = nutation in longitude (arc seconds)
// vnut(2) = nutation in obliquity (arc seconds)


And here's the output from the program.

IAU 1980 NUTATIONS (arc seconds)

nutation in longitude 14.4505645343

nutation in obliquity −6.05167374791

The attached zip file also includes a PDF document that provides more information about this algorithm.
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