The ICRF1 maintenance and extension catalogue, ICRF-Ext.1, includes updated coordinates for the 608 extragalactic radio sources from the ICRF, as well as 59 additional sources. The catalogue incorporates data collected between December 1994 and April 1999 from both geodetic and astrometric observation programs.
| Content | This dataset provides the equatorial coordinates of extragalactic radio sources observed at J2000.0 using Very Long Baseline Interferometry (VLBI). Number of objects: 667 | |
| Accuracy | The uncertainties in the coordinates are provided for each object and are given in the following ranges: | |
| Right Ascension [s] | 0.000017 - 0.053679 | |
| Declination ["] | 0.00026 - 0.52054 | |
| Updates | Updates to the ICRF are released at irregular intervals, typically every few years. ICRF-Ext.2 ICRF2 ICRF3 | |
| Public access | IERS ICRS Product Centre: https://hpiers.obspm.fr/icrs-pc/icrf/index.php IERS Data Center: https://datacenter.iers.org/products/reference-systems/celestial/icrf1-ext1/ | |
| Format | For a detailed description of the format, refer to the contents of the data file. | |
| Documentation | Gontier, A.-M.; Ma, C.; Arias, E.F.; Eubanks, T.M.; Fey, A.L.; Jacobs, C.S.; Sovers, O.J.; Archinal, B.A.; Charlot, P. (2002). Establishment of the International Celestial Reference Frame. Advances in Space Research, 30(2), 185–193. https://doi.org/10.1016/S0273-1177(02)00283-1 | |
| Product center | IERS ICRS Centre | |
