Volume 15, Number 1, March-June 1999
By Joseph King
Some years ago, Goddard's Dr. Joseph Gurman built and managed a facility for science and data operations for the 1980-launched Solar Maximum Mission spacecraft. Over the years the facility has evolved into the multimission Solar Data Analysis Center (SDAC) and is widely valued throughout the NASA and international solar physics community as that community's primary solar data management and distribution center. Much of the current focus of the SDAC is on data from the 1995-launched ESA/NASA SOHO (SOlar and Heliospheric Observatory) mission and on data from the 1998-launched NASA TRACE (Transition Region And Coronal Explorer) mission. The home page of the SDAC is at http://umbra.nascom.nasa.gov/sdac.html.
As the SDAC continued to strengthen and NSSDC lost its solar physics "acquisition scientist" (David Batchelor) some years ago, the SDAC and NSSDC have increasingly assumed the roles of "active archive" and "permanent archive" for solar data. NSSDC's solar pages point to the SDAC for data and for expertise about data. An example of the SDAC-NSSDC interaction follows.
Over the past few years, NASA has funded restorations of various space science data sets with the expectation that restored data would be archived at NSSDC if not elsewhere. Among the solar physics data sets falling into this category were solar X-ray and UV data from the Solrad 11 spacecraft launched in 1976. Robert Kreplin and A.J. Martin of the Naval Research Lab worked on this data restoration project and contacted NSSDC for guidelines on various technical matters. NSSDC in turn contacted SDAC to share in this interaction. SDAC's Douglas Biesecker has become the "acquisition scientist" for NSSDC and for SDAC for this activity.
The Solrad data are formatted telemetry-level data. They will be provided to the SDAC and to NSSDC on CD-WO disks, accompanied by detailed mission, experiment, and data documentation; PC-compatible Fortran code for extracting X-ray and UV data from the CDs and IDL code for data display. SDAC will provide support to users of these data, and NSSDC will ensure the long-term availability of these data.