The Internet Foundation Applying the Internet to Solve Global Problems

Time and General Relativity

Other notes at 

• IAU Working Group on Relativity in Celestial Mechanics and Astrometry (RCMA) - RKC

• IAU Resolutions, Discussions and Recommendations B3, B6 - RKC

• Earth Gravitational Model Status - RKC

Groups

• IAU: The International Astronomical Union
  • Division I Fundamental Astronomy
    • IAU-BIPM Joint Committee on General Relativity for Space-Time Reference Systems and Metrology
      • BIPM-IAU Joint Committee on general relativity for reference systems and
  • Commissions
    • Commission 19 Rotation of the Earth
    • Commission 20 Position and Motions of Minor Planets, Comets and Satellites
    • Commission 7 Celestial Mechanics and Dynamical Astronomy
    • Commission 4 Ephemerides
  • International Astronomical Union, IB82 - B3, B6
  • The International Astronomical Union - IB81 - B3, B6
• IAU WG on RCMA
  • Members of the IAU WG on RCMA - Members of the IAU WG on RCMA and their Addresses
  • Circulars of the IAU WG on RCMA

• BIPM: Bureau International des Poids et Mesures
• IAG: International Association of Geodesy
  • IAG Earth Tide Commission (ETC)
  • GGG2000 - IAG International Symposium on Gravity, Geoid, and Geodynamics 2000
  • 14th International Symposium on Earth Tides
• IERS: International Earth Rotation Service
• IUGG: International Union for Geodesy and Geophysics
• The Royal Observatory of Belgium - Earth Tides - Earth Rotation, Precession - Nutation - Gravimetry - Time

  • International Centre for Earth Tides

• Institut de mecanique celeste et de calcul des ephemerides - http://www.bdl.fr - English

• IGS -- International GPS Service

  • Time Transfer Project - IGS-BIPM Pilot Project to Study Accurate Time & Frequency Comparisons using GPS Phase & Code Measurements

Sergei A. Klioner's Home Page - S.A. Klioner's publications - Sergei A. Klioner's Recent Preprints

IAU Colloquium 180 - Towards Models and Constants for Sub-Microarcsecond Astrometry

• Summary and Resolutions

  • Resolution 3. Definition of Barycentric Celestial Reference System and Geocentric Celestial Reference System

  • Resolution 4. Extended relativistic framework for time and frequency comparisons and realization of coordinate times in the solar system

  • Resolution 5. Post-Newtonian Potential Coefficients

  • Resolution 9. Re-definition of Terrestrial Time TT

  • Resolution 10. Coordinated Universal Time

• IAU Colloquium 180 - First Announcement

  • Moreover, a new set of values of fundamental astronomical constants (parameters) is needed consistent with ICRS accuracy and expressed in units that are properly specified, in a relativistic sense, in the barycentric and geocentric reference systems defined by previous IAU resolutions. Procedures for dealing with the small offsets of the ICRS from the system defined by the kinematics of Earth rotation must also be specified for those observations sensitive to it. Furthermore, the needed change in the precession/nutation model will require reconsideration of the definition of Universal Time.

• List of Participants

INFEO

BIPM Joint Committees with other organizations

• Joint Committee of the BIPM and the International Astronomical Union - The aim of this Joint Committee of the BIPM and the IAU is to pursue the work carried out by the former CCDS working group on the application of general relativity to metrology. The particular task of the Joint Committee is to draw up conventions for space-time reference systems in the context of general relativity. The chairman of the Joint committee is Dr G. Petit of the BIPM.