Thanks to Steve for the reference: http://danof.obspm.fr/IAU_resolutions/Resol-UAI.htm
I reproduce below a resolution of more specific relevance to this discussion that was made at that meeting of the International Astronomical Union. I'm glad the IAU is looking at a wider range of options than the International Telecommunication Union Radiocommunication Study Group is. The IAU working group is due to report in mid-2003. Who knows more about this IAU working group and their discussions? This brings up the broader question of who is involved in this decision making process. ITU CCIR Recommendation 460-4. (188) is available at http://www.cl.cam.ac.uk/~mgk25/volatile/ITU-R-TF.460-4.pdf It is "RECOMMENDATION 460-4 STANDARD-FREQUENCY AND TIME-SIGNAL EMISSIONS" and contains this language: UTC is the time-scale maintained by the BIPM, with assistance from the International Earth Rotation Service (IERS), which forms the basis of a coordinated dissemination of standard frequencies and time signals. That leads me to believe that while the ITU wrote the recommendation on how to *disseminate* UTC, the actual legal basis for determining UTC rests with the BIPM, which is part of the General Conference on Weights and Measures, which also handles the International System of Units (SI). http://www.bipm.fr/enus/ Neal McBurnett http://bcn.boulder.co.us/~neal/ GPG/PGP signed and/or sealed mail encouraged. Keyid: 2C9EBA60 IAU Resolutions Adopted at the 24th General Assembly (Manchester, August 2000) Resolution B2 Coordinated Universal Time The XXIVth International Astronomical Union General Assembly, Recognising 1. that the definition of Coordinated Universal Time (UTC) relies on the astronomical observation of the UT1 time scale in order to introduce leap seconds, 2. that the unpredictability of leap seconds affects modern communication and navigation systems, 3. that astronomical observations provide an accurate estimate of the secular deceleration of the Earth?s rate of rotation, Recommends 1. that the IAU establish a working group reporting to Division I at the General Assembly in 2003 to consider the redefinition of UTC, 2. that this study discuss whether there is a requirement for leap seconds, the possibility of inserting leap seconds at pre-determined intervals, and the tolerance limits for UT1-UTC, and 3. that this study be undertaken in cooperation with the appropriate groups of the International Union of Radio Science (URSI), the International Telecommunications Union (ITU-R), the International Bureau for Weights and Measures (BIPM), the International Earth Rotation Service (IERS), and relevant navigational agencies. On Thu, Jan 30, 2003 at 04:25:22PM -0800, Steve Allen wrote: > The resolutions that have established the change have happened over > the past four meetings of IAU General Assembly. > > The most recent set of resolutions which switched things from the old, > non-inertial definitions to the new ones is visible at > http://danof.obspm.fr/IAU_resolutions/Resol-UAI.htm