Presentation on theme: "PERICLES FP-7 approach to the preservation, reuse and distribution of observational data: the example of solar spectral irradiance data obtained in space."— Presentation transcript:
PERICLES FP-7 approach to the preservation, reuse and distribution of observational data: the example of solar spectral irradiance data obtained in space C. Muller
What is the role of B.USOC in ISS data flow? B.USOC manages the experiments, transmits the data requested by the scientist to the UHB and keeps a data repository according to ESA policy. The data transmitted by ColCC to the USOC’s is in the CCDS format (consultative committee for space data standards), it is in packages regrouping all experiments assigned to a USOC.
More explicitly in the case of SOLAR B.USOC supplies the data requested by the scientist using a dedicated software, the YAMCS which parses the data flow so that each experimenter receive what he requests and the essential monitoring parameters are transmitted to the screens of the operators. The YAMCS is a proprietary B.USOC software developed by SpaceAps, it is also used for ERA (European Robotic Arm)
Yet Another Mission Control System The Columbus Mission Control System used in Col-CC is built around the Astrium CGS software which was the Columbus EGSE ESA has decided to build a “stripped down” version of the Columbus MCS and distribute it to all the USOCs, calling it CD-MCS (Columbus Decentralized MCS). None of the payloads which the USOCs are operating have been developed using the CGS software, thus the CD-MCS is not particularly suited for the operations of these payloads. YAMCS has been gradually developed as a set of tools needed to complement CD-MCS functionality, in order to support operations in the B.USOC and the Erasmus USOC. 4
Yet Another Mission Control System The main needs that drove the development of YAMCS are: Multiple parallel commanding/monitoring chains Complicated data structures and encodings used by some instruments. Need for special telemetry processing that goes beyond what can be achieved with a template based definition. Need to comply to strict security rules when offering access to telemetry/telecommand to remote users. Although the CD-MCS does contain an archiving system (called HRDP), it does not offer the possibility to easily inspect/retrieve data from the archive and to assess the archive completeness. 5
Thus what happens to SOLAR data? SOLAR data is put into the data flux of B.USOC by ColCC, ColCC manages a 72hours buffer, the SAN (storage area network), after the data becomes the the sole responsibility of the USOC. Data are sent in the CCSDS format (Consultative Committee on space Data Standards). The data packages are not differentiated by experiments, B.USOC uses the YAMCS to produce the different fluxes. Storage of the data package is done in the HRDP (High Rate Data Processor)
HRDP and ESA data policy HRDP is a rack of servers and network equipments, it is owned by ESA and installed at the respective USOC’s, it is highly secure and can only be accessed by certified personnel. The data stored on HRDP are in the original CCSDS format. In our case, only a YAMCS application could retrieve SOLAR data. HRDP has its own backup hardware and procedures. ESA present data policy: absolutely no outside access to the HRDP, data distribution limited to PI, up to now, B.USOC has not been allowed to supplement HRDP storage by an accessible storage. B.USOC does not archive the data it sent to the PI’s nor the scientific products generated by the PI’s. Data storage at USOC’s is limited to 10 years. All the negative aspects of this list can be solved by a revised data policy. (and a corresponding adaptation of means for the USOC’s)
New developments Replacement of HRDP : the HRDP hardware is no longer maintained by the manufacturer, it will be replaced by a virtual machine at ColCC, in the meanwhile, the B.USOC HRDP is still fully functional and has a valid back-up. A new draft of the data policy has been circulated, if confirmed by ESA, it increases the data management capabilities of B.USOC. In the meanwhile, B.USOC strictly respects ESA data policy and does not distribute any ISS data without explicit ESA authorisation.
ULISSE and PERICLES ULISSE and PERICLES FP-7 programmes are B.USOC attempts to find realistic solutions to data archiving, distribution, preservation and Long Term Data Preservation. ULISSE: ; developed a model of data distribution, applied to a network of ground based UV stations. PERICLES: : a very ambitious programme covering evolution of data and scientists.
Why do we want to preserve SOLAR data? Solar irradiance variations have an influence on climate, both in long term trends and maybe in short term fluctuations which could trigger instabilities.
The ULISSE model Tested on the ground based solar UV network of IASB- BIRA. (SOLAR data could not be used with respect to data policy). ULISSE uses a mirror of the original data where the data customer builds a basket with all the data he needs by instrument, station and time. Once the basket is built, the customer downloads it as a compressed file. The mirror is synchronised to the actual data base once a day.
This distribution system was a success essentially because the UV station programme started in FP-4 and FP-4 imposed a very easy to use format: the FLEX format, unfortunately, the EU attempt to make it a standard failed. This distribution system is still used for test-beds of new products, it is protected against any damage to the original data.
PERICLES A FP-7 IT project aimed at “preservation by design” of large data sets. IT partners and partners in the media and scientific data. a key challenge here is the need to cater for the evolution of user communities in circumstances that are unanticipated when the data was created. PERICLES will address this by considering the evolution or socialization of data sets. The IT partners are already present in the DCC (data curation centre).
PERICLES partners: 10 IT and two case studies. 1 King’s College London KCL UK: ccordinator 2 University of Borås HB Sweden: IT (large fashion and textile data base) 3 CERTH-ITI CERTH Greece: IT 4 Dotsoft DOT Greece: IT 5 Georg-August-Universität Göttingen UGOE Germany: IT (scientific library) 6 University of Liverpool ULIV UK: IT 7 Space Application Services SpaceApps Belgium: IT 8 Xerox XEROX France: IT (company link to the parallel NASA effort). 9 University of Edinburgh EDIN UK: IT 10 Tate Gallery TATE UK: media case 11 Industrious Media IM UK: IT 12 B.USOC (IASB BIRA) BUSOC Belgium: space case
First step: data catalogue Engineering Documentation. Operations documents Documents generated during operations. Data generated during operations Science data 29 items categories have been identified at B.USOC including the science data in HRDP. Scientific products and their metadata: still to be surveyed.
Second step: data preservation Regroup all the data in a single data base. Convert HRDP data to a format accessible by qualified users. Scientific products and their metadata: should also be part of the preserved data. This aspect is even central to the new (Nov 2014) NASA preservation policy. Then, the processes developed by the IT partners can be implemented.