The World Data Center system is an international confederation of data centers originally established in 1955 to support the exchange and archiving of data generated by the 1957-8 International Geophysical Year. A more complete World Data System description is available from the ICSU Web Page.
World Data Center for Satellite Information (formerly the World Data Center-A for Rockets & Satellites) is hosted by the NASA Space Science Data Coordinated Archive. WDC SI has responsibilities for spacecraft launch and other descriptive information capture and dissemination. WDC SI serves as a conduit for requests from the international community for data from the NSSDCA data archives.
Maintained by: U.S. National Aeronautics and Space Administration, Goddard Space Flight Center, NASA Space Science Data Coordinated Archive (NSSDCA).
Summary of data held: WDC SI holds information about rocket, satellite, and space probe launches, although information on rocket launches is no longer maintained current; satellite orbit elements and ephemerides; descriptions of spacecraft and experiments. NSSDCA holds much data, mainly from NASA space science spacecraft, which are accessible to non-U.S. persons in offline form by requests directed to WDC SI, and, for a subset of NSSDCA holdings, electronically with no specific WDC SI involvement.
User services: Dissemination of spacecraft launch information, with newly assigned international identifiers, within days of launches; open to visitors during normal working hours (advanced notification recommended); passes international data requests to NSSDCA for NSSDCA-held data; online information about NSSDCA data holdings at http://nssdc.gsfc.nasa.gov/, which links to the NSSDCA Master Catalog and other data and services.
Publications: SPACEWARN Bulletin (http://nssdc.gsfc.nasa.gov/spacewarn/) which summarized spacecraft launches monthly, was discontinued in 2011.