CASSIS Moving forwards on standards and interoperability

1. CASSISMoving forwards on standards and interoperability R.D. Bentley (UCL-MSSL) and the CASSIS Consortium ESWW-7, Bruges, November 2010

2. Coordination Action for the integration of Solar System Infrastructures and Science • CASSIS is a Coordination Action funded under Research Infrastructures within the Capacities programme of FP7 • Started 1 June 2010, duration 36 months • CASSIS intended to facilitate science within the Solar System by improving the interoperability between data and services in all domains • CASSIS brings together three FP7 projects that are directly relevant to this issue – HELIO, EuroPlanet RI and SOTERIA • Desire is to engage as many other groups as possible in the discussions, from Europe and the rest of the world • Web site: http://www.cassis-vo.eu

3. CASSIS Consortium • Participants include groups from the three FP7 project – HELIO, Europlanet RI and SOTERIA. • Groups from the US were added during the negotiation phase. CASSIS interested in broadening the international aspects of the project by extending invitations to key organisations elsewhere • Whether other disciplines should be included is being considered – e.g. climate studies,

4. CASSIS is all about interoperability! • Solar System Science has traditionally been undertaken within a number of separate disciplines • Many aspects of the system are inter-related • Difficult to address them because of the lack of the integrating tools and techniques • Advances in technology means that the intrinsic differences between disciplines are being addressed • Manifest by differing data formats and other dependencies • The three projects involved have already made progress • Each is making significant improvements to the infrastructure that supports their communities, increasing ability to do science • Necessary to coordinate the efforts of these and other projects in order to help break down the inter-disciplinary boundaries barriers • CASSIS intended to take things to the next level by cooperating in a number of areas • Enabling new combinations of interdisciplinary studies

5. Cooperation & Discussion • Areas of cooperation include: • Investigating ways to improve the interoperability between data and metadata from the domains, and the possibility of sharing services, including metadata resources. • Coordinating the use of standard within the projects and reflect any changes that are required to organizations like the IVOA and IPDA. • Coordination of the dissemination activities of the projects in order to create a more coherent and comprehensive approach • Two principle means of discussion: • Community Consultation Meeting will be used to gather input from the wider community • Vision for Solar System Science Workshops are planned to bring key players together in order to lobby the case for solar system science with the decision makers and funding agencies

6. Standards and Interoperability • Drive for interoperability comes from increasing desire to undertake cross-disciplinary studies • HELIO is a Virtual Observatory that is trying supports this • Domains involve include solar, heliospheric, planetary, geophysics… • To achieve its objectives, HELIO must address a number of issues • These are the things make everything possible… • Must support a search across several domains • Search based on metadata and derived products • Search related to phenomena evolving in 4-Dimensions • Need to condition the metadata to ensure that temporal and spatial coordinates are homogeneous and interoperable • Must provide integrated access to data from many domains • Different file formats, ways of storing, handling and using the data • Variety of access techniques & protocols (http, ftp, Web-services…) • Accessibility depends on how providers have organized things

7. Standards and Interoperability • HELIO is developing data models to describe the systems that we trying to integrate • Single data model is not realistic option • Trying to create a data model that over-spans the others… • Based on models from EGSO, SPASE, etc. • Data model is important since we need to annotate the metadata to properly describe quantities • Unambiguously define the parameters involved • Put them in context of other information that are used • Developing standards for files that HELIO is producing • Include suggested sets of quantities, etc.that should be used • Annotation also an important part of this activity • If adopted elsewhere, ideas engender interoperability • Developing recommendation for providers about how to naming and storage strategies that would make their data archives more interoperable

8. Some simple guidelines for Providers... • File Names – There are no hard and fast rules, but the name needs to be sufficiently unique that: • The type and origin of the file can easily be identified (time of observation?) • The file can exist without causing confusion when removed from the context of where it is normally stored • Directory Structure – A hierarchical directory structure makes it easier to find files (and is strongly preferred) • Ideally the structure should be a tree based on dates • Essential for resource-poor providers; beneficial for a data centre • Summary of Observations – It simplifies access if the archive maintains a summary of the observations that have been made • Particularly useful if all the observations are not available on-line

9. Some simple guidelines for Providers... • File Metadata – It is essential that all files contain good metadata describing the characteristics of the observations • If metadata are not properly formed, it may be impossible to use the data in some circumstance • Files should be in some standard format • FITS, CDF or similar • Need to try to push down the boundary between the standard and domain specific areas of the metadata • Some form of annotation would be beneficial Standard Domain specific

10. Annotation of data that are used/created • Trying to identify lists that could be added to the HEC • SOTERIA using HELIO HEC technology for its event lists • HELIO uses file in VOTable format to transfer information • Lists that could be used by external communities should be fully annotated with UCDs and utypes – also useful internally! • Unambiguously defines what the quantities are and mean • CASSIS looking for help to define utypes and UCDs for the Solar System • Part of the comprehensive, over-spanning data model • UCDs and utypes are concepts defined by the International Virtual Observatory Alliance (IVOA) • Existing UCDs not really applicable toheliophysics and HELIO needs to develop a new set!

11. Harmonizing spatial coordinate systems STEREO-B, SOHO and STEREO-A on 22/2/2010 when the STEREO spacecraft were ~65º behind/ahead of Earth • In heliophysics need to use data from many points in the Solar System • Need to be able to relate features seen from different vantage points • Need to be able to interpret coronagraph (plane-of-sky) observations from different viewpoints and relate them to motion of material in the heliosphere • Need to relate these to in-situ observations made at various locations • Need to be able to track features and follow effects into planetary environments • Interoperable set of coordinates required to make things work • Would be useful if everyone tried to use similar set…

12. STEREO – Inhomogeneous metadata • The STEREO event lists for IMPACT have problems: • Very different ways of expressing time • Location of spacecraft not explicitly included • No information on “local” solar B angle… • Good for creativity; very poor for interoperability

13. Summary • Standards and Interoperability are good for all • Need to find ways to improve quality of the data • This must be done in a way where the provider can see the benefit • Should not forget the back ground information!! • Need to find way of making the data more accessible • Technology is no longer an issue • Need to also look at the definition of services and see if we can improve interoperability • How parameters are called what they are, annotation… • The funding bodies need to insist that projects • Produce data that comply with minimum standards and are accessible • Consider interoperability in their data management plans

14. LOCAL VO Standards and Interoperability are good for all We look forward … … to your cooperation