This is a collection of links to various IAU recommendations and standards. It does not claim to be complete.

Resolutions | The link to the IAU list of Resolutions adopted at the General
Assemblies |

2000-2012 Summary: Reference Systems | This webpage gives a summary of the IAU and IUGG resolutions that relate to reference systems, and in particular those after the IAU 1997 adoption of the International Celestial Reference System and Frame (ICRS/ICRF). |

SOFA | IAU Division A Standards Of Fundamental Astronomy |

The IAU's SOFA service has the task of establishing and maintaining an accessible and authoritative set of algorithms and procedures that implement standard models used in fundamental astronomy. The service is managed by an international panel, the SOFA Board, appointed through IAU Division A - Fundamental Astronomy. SOFA also works closely with the International Earth Rotation and Reference Systems Service (IERS). | |

WG NSFA | Working Group for Numerical Standards of Fundamental Astronomy: |

This IAU Division A WG provides the IAU system of astronomical constants (2009/2012) and a list of Current Best Estimates. | |

WG CCRE | Working Group for Cartographic Coordinates and Rotational Elements |

This IAU Division A/F WG has the responsibility to define the rotational elements of the planets, satellites, asteroids, and comets of the solar system on a systematic basis and to relate their cartographic coordinates rigorously to the rotational elements. | |

ICRF2 | The 2nd Realization of the International Celestial Reference Frame by VLBI. |

This IERS Technical Note produced by the IERS / IVS Working Group describes the generation of the second realization of the International Celestial Reference Frame (ICRF2) at radio wavelengths using nearly 30 years of Very Long Baseline Interferometry (VLBI) observations. ICRF2 contains precise positions of 3414 compact radio astronomical sources, more than five times the number as in the first ICRF, hereafter ICRF1. There is a Division A WG working on Third Realisation of International Celestial Reference Frame. | |

WG NFA | Division 1 WG on Nomenclature for Fundamental Astronomy, 2003-2006. |

The IAU recommendations on nomenclature relating to the IAU 2000A/20006 resolutions concerning fundamental reference system was published in the The IAU Transactions XXVIB. The WG produced a glossary of terms. and a process chart illustrating the transformation from the ICRS to the observed places of stars. | |

Nominal Units WG | See IAU 2015 Resolutions, alternatively the arXiv.org links below publish full details of both resolutions:- |

Resolution B2 for the recommended zero points for the absolute and apparent bolometric magnitude scales and | |

Resolution B3 for the recommended nominal conversion constants for selected solar and planetary properties. | |

IAG GGOS | GGOS Bureau of Products and Standards |

A major goal of the GGOS BPS is to coordinate the establishment and
maintenance of unique standards for the processing of geodetic
observations for geometric and for gravimetric techniques within
GGOS and IAG. The geodetic standards include, i.e., physical units
and constants, mathematical-physical models for geodetic
observations and reduction models. Various standards have been
defined for specific geodetic fields (e.g., IAG Resolutions, IERS
Conventions) which form the basis for the work of the BPS.
This reference work,
Inventory of Standards and Conventions used for the Generation of IAG Products
is included in
The Geodesist's Handbook 2016
(pages 907-1205), an open access article in the Journal of Geodesy (October 2016, 90, Issue 10). | |

SI Units and the Astronomical System of Units |
The international system (SI) of units, prefixes, and symbols should be used for all physical quantities except that certain special units (see the SI brochure on the BIPM web site for details) may be used in astronomy, without risk of confusion or ambiguity, in order to provide a better representation of the phenomena concerned. |

It is convenient for astronomers to use, for certain applications, an
astronomical system of units, in which the unit of mass is equal to the
mass of the Sun, M_{S}, the unit of time is one day, D,
and the unit of length is the astronomical unit of length (or simply
the "astronomical unit"). | |

Note that the astronomical unit (au) was re-defined in
Resolution B2
of the 2012 IAU GA, so that: 1 au = 149 597 870 700 m. This unit is
listed in Table 6
of the SI Brochure: The International System of Units (SI) (8th edition, updated 2014.) | |

Ephemeris Access | IAU Commission 4 Working Group (2010-2015) recommends a standard format for ephemerides. |

This format uses the widely used SP and PC kernels (designated SPK and PCK, respectively), slightly modified to meet the needs of all the current, widely available, high accuracy planetary ephemerides. Provision has also been made to allow for future innovation with backward compatibility. The software packages CALCEPH and SPICE support this format, so users can have confidence that these packages will be able to read any of these ephemerides. This in no way invalidates software written by any group for reading a particular ephemeris. | |

IAU-Style Manual | The IAU Style Manual - a 4.7MB PDF file, by G.A. Wilkins,
for Commmission 5, published in chapter 8 of the IAU Transactions
XXB (1989). |

The following IAU web page gives the IAU Rules, Guidelines and Instructions for Proceedings has additional information, such as LaTeX templates and Abbreviations in references to Serial Publications. |