Summary and Recommendations
Abstract
The purpose of the IAU Colloquium 180 was to prepare a series of resolutions regarding the specification of the International Celestial Reference System (ICRS) for consideration by Joint Discussion 2 at the XXIV IAU General Assembly. These resolutions provide definitions, standard algorithms, and parameters to link observable quantities with reference coordinates within the ICRS. Specifically recommended were definitions of the celestial intermediate pole and celestial ephemeris origin, an improved precession/nutation theory, and a new set of standard values for astronomical constants. IAU Colloquium 180, attended by 96 participants, was organized with 32 invited speakers and 44 poster papers. Sessions were devoted to Celestial Reference Systems and Frames, Relativistic Considerations for High Precision Dynamical Astronomy, Precession and Nutation, Time and Constants, and Requirements for Improved Accuracy in Celestial Reference Systems. The colloquium also discussed plans for future observations of the defining elements of the celestial reference frames necessary to support present and planned high-precision astrometric programs. Each resolution was given an initial presentation and thorough discussion until a final version of each was adopted by a majority of the attendees. Resolution titles were as follows: (1) Maintenance and Establishment of Reference Frames and Systems, (2) Hipparcos Celestial Reference Frame, (3) Definition of Barycentric Celestial Reference System and Geocentric Celestial Reference System, (4) Post-Newtonian Potential Coefficients, (5) Extended Relativistic Framework for Time Transformations and Realization of Coordinate Times in the Solar System, (6) IAU 2000 Precession-Nutation Model, (7) Definition of Celestial Intermediate Pole, (8) Definition and Use of Celestial and Terrestrial Ephemeris Origin, (9) Re-definition of Terrestrial Time, (10) Coordinated Universal Time, and (11) Definition of a Spectroscopic Radial Velocity Measure.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 2000
- Accession Number
- ADA435906
Entities
People
- P. K. Seidelmann
Organizations
- United States Naval Observatory