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Densification of the Optical Reference Frame (Commission 8)


Objectives and History

This group works towards obtaining high precision astrometry of optical sources and putting those on the system of the ICRS. This is being undertaken for the express purpose of increasing the density (number of stars per square degree) beyond that of the Hipparcos Catalogue, which defines the optical reference frame.

The Densification of the Optical Reference Frame sub-group originated under the International Celestial Reference System (ICRS) Working Group sponsored by Division I of the International Astronomical Union. At the 2003 IAU General Assembly, the ICRS Working Group was essentially dissolved. The Densification of the Optical Reference Frame group was moved under Commission 8. At the 2006 GA in Prague this WG was confirmed to continue for the 2006-2009 period.

At left are links relevant to the Densification sub-group, including a summary of the current status of Optical Astrometric Surveys.

The following is another useful resource, summarizing astrometric surveys past, present and future.


Send comments to Norbert Zacharias (nz at usno.navy.mil)

last update: 2009 July 06