The IRIS Bulletin A ceased publication with issue no. 130, December 1994. Routine processing of VLBI data and the electronic distribution of Earth orientation results ended on 31 December 1994. Existing VLBI results will continue to be available electronically for an indefinite period.
Earth orientation data users are referred to the similar results available from the U.S. National Earth Orientation Service (NEOS) which prepares and distributes the weekly NEOS Bulletin (IERS Bulletin A) . This Bulletin can be obtained by anonymous ftp to the USNO node `maia.usno.navy.mil' in the directory `ser7' and the file `ser7.dat' or by using Mosaic to the URL link http://maia.usno.navy.mil/. In addition, the IERS publishes its monthly "IERS Bulletin B", which is available via anonymous ftp to `mesiom.obspm.fr'. Both publications are also available by postal mail.
All operational activities associated with coordinating and scheduling the NEOS and the IRIS Intensive VLBI observing sessions became the sole responsibility of USNO as of 01 January 1995. Communications should be directed to Marshall Eubanks at `firstname.lastname@example.org'. Similarly, IRIS-S operations are directed by the Bonn VLBI group: Arno Mueskens at `email@example.com' and Axel Nothnagel at `firstname.lastname@example.org'. The SHS network has been reconfigured for 1995 as an interagency activity under the new name of SOUTH TRF.
NOAA remains committed to the VLBI technique. We recognize the vital function that VLBI fulfills in reinforcing the terrestrial reference frame, establishing a stable inertial celestial reference frame, and in determining regular, reliable Earth orientation parameter values, especially UT1. These results are required to sustain important NOAA programs and objectives. Therefore, we will continue to support the observational activities at Hartebeesthoek, S. Africa; Hobart, Tasmania, Australia; and Fortaleza, Brazil. We will also continue to participate actively in the VLBI observational programs sponsored by the U.S. National Earth Orientation Service as well as other agencies and institutions.
NOAA is proud of its early, prominent part in helping to exploit VLBI as an effective tool for geodynamical studies and monitoring Earth orientation variations. It is with considerable reluctance that we are compelled to make this change, but we welcome the new challenges that lie ahead.