Maintenance of the ICRS

The IAU has charged the IERS with the responsibility of:

• Monitoring the ICRS;
  
  
• Maintening the ICRF:
  • promoting and coordinating observations;
  • monitoring source structures;
  • updating the catalogue;
  
  
• Maintening the link of optical reference frames to ICRS:
  • assessing the accuracy with the main astrometric catalogues in various wavelengths;
  • monitor the evolution of the links;
  • this task is primarily to be performed on the Hipparcos catalogue as the primary optical reference frame;
  
  
• Monitoring the evolution in time of the instantaneous positions and motions of the equinox and ecliptic;
  
  
• Assisting in the collection and distribution of observations of millisecond pulsars.