v1.4.2

[attipaci]

Bug fix release with updated nutation models.

Fixed

• Inconsistent default CIO file location #201: By default expect to find the CIO locator file (CIO_RA.TXT or cio_ra.bin) in its install location, e.g. in /usr/share/supernovas or as set via the datadir or prefix install locations.

• IAU2006 nutation rescaling missed time dependence #202: The P03 recommended rescaling of the original IAU2000A nutation model to IAU2006 (see Coppola, Seago, and Vallado 2009) was not correctly implemented in the prior 1.4 releases. The resulting errors are around or below 40 μas for the present era, and slightly larger than the model discrepancies (~10 μas) that the rescaling was meant to address.

Changed

• Upgrade nutation models to IAU2006 (i.e. IAU2000A R06). #206: Updated nutation models: iau2000a() now uses IAU2000A R06 model coefficients (see https://hpiers.obspm.fr/eop-pc/models/nutations/nut.html), making it dynamically consistent with the IAU2006 (P03) precession model, which was already implemented by NOVAS and SuperNOVAS. iau2000b() is now a truncated version of the above, keeping terms with amplitude <100 μas, resulting in similar number of terms and precision as the original IAU2000B model. And, nu2000k() has been rescaled according to Coppola, Seago, & Vallado (2009) to also bring it in line with the IAU2006 (P03) precession model.

• make benchmark now uses any user-defined CPPFLAGS, automatically adding the include/ directory to it.

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This discussion was created from the release v1.4.2.