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The ISTP mission operations and data system and the associated data products provide the Space Physics community with an integrated environment, uniform data products and science planning that have been designed and implemented from the outset to substant
ially enhance the science return. As shown in Figure 1.9 a number of NASA and Goddard Space Flight Center Facilities (GSFC) play key roles in the collection and dissemination of the data. The NASA Deep Space Network (DSN) commands and collects the data f
rom all the spacecraft. At the Goddard Data Capture Facility (DCF), the raw data are assembled into level-zero files (the first level of processed data). The Goddard Data Distribution Facility (DDF) is responsible for delivering the data from each investi
gation to the scientists (generally on CD-ROMs).
One of the significant technological developments driven by ISTP in the data arena is the ISTP/IACG Common Data Format (CDF), which encapsulates scientific data and its associated metadata in a form that allows the data products to be archived, retainin g their long term usefulness and allows automated tools for display and analysis of the data to be developed. ISTP/IACG CDF, developed and maintained by the Space Science Data Operations Office (Code 630 at the Goddard Space Flight Center), is now an indu stry and international standard that is supported by RSI's IDL and Mathworks' Matlab (shortly). ESA’s Cluster Project has standardized on ISTP/IACG CDF for the Summary and Prime Parameter data bases from the 44 instruments on the four Cluster spacecraft and it is an international standard for IACG space physics data. ISTP has developed a number of tools that take advantage of the ISTP/IACG CDF structure, e.g., CDAWeb and Key Parameter Visualization Tool, that has substantially contributed to the availability and usability of the ISTP data products. The Central Data Handling Facility (CDHF) is the central repository and coordination point for spacecraft, ground-based data, and for data from other related missions, e.g., GOES and LANL geostationary spacecraft, SAMPEX, SOHO, FAST, IMP-8 and eventuall y ACE and CLUSTER. One of the CDHF's most important functions is the processing of POLAR, WIND and GEOTAIL level-zero data into overview or summary data known in ISTP as "key parameters" and for the ingestion of key parameters from the missions mentioned above. These key parameters are produced in near real time by CDHF and are critical to the initial identification and evaluation of solar-terrestrial events. They constitute an efficient database which can be used as a catalog of a much larger volume of d ata. Currently this key parameter database consists of approximately 20 Gbytes of scientific measurements that span geospace from the forward libration point to the Earth's surface and the deep magnetic tail, and in time from September 1992 to the present. This database continues to grow daily, and is available to, and is being used by, the world-wide community of space physicists. A number of key parameters from instruments on WIND and POLAR are computed in real-time for use by NOAA and the Air Force for space weather predictions and by space scientists who require real-time knowle dge of the solar wind and/or auroral activity in support of rocket and balloon campaigns. The detailed analysis of the data is performed by the investigators using their own computing facilities, called Remote Data Analysis Facilities (RDAFs), at their home institutions. All are electronically connected to each other and to the NASA facilities via the NASA Science Internet (NSI). From the RDAFs, the investigators are able to access level-zero data and the key parameter data both electronically and on CD-ROM, using the key parameters as a guide to select intervals of high scientific interest on which to concentrate their analysis. |
Figure 1.9. Schematic representation showing the flow of data through the
ISTP ground system.
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