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Virtual Observatory Standards and Systems for Data Centres and Large Projects Other Astronomical News One of the “Hands-on Workshops” at the con- ference. experiment and see the changes to the So all those interested in outreach should final image product through different tech- go to the IAU Working Group web-page: niques within Photoshop. http://www.communicatingastronomy.org and enrol on the “Supporters” sign-up Lisa Frattare and Robert Hurt extended sheet so that we can keep you informed this theme with two workshops on more of progress and future events. The pro- advanced image processing ‘tips & tricks’ ceedings of this conference are currently for how to clean and correct the colour being edited and are planned for publica- images as well as make a better com- tion in September. position. Greg Bacon (NASA/STScI) pre- sented a session on how to undertake The organisers wish to acknowledge simple animation studies. Finally in this financial and infrastructure support from theme, Martin Kornmesser and Lars ESO, as well as support from ESA and Lindberg Christensen hosted a session the IAU. devoted to producing your own DVD. Govert Schilling gave two sessions devot- ed to how to write for the media and an interactive discussion on the rights and ) 2 ( e l wrongs of producing a good press re- b b u lease. Terry Mahoney gave an overview of H / A S the basic contents of a toolkit for astron- E , n e omers involved in outreach and the do’s ly suggested a possible theme for the s l e i and don’ts of a successful programme. next conference, which will be in 2007. N . H . There is no doubt that this focused skills- L : s o based workshop-style was extremely The meeting was organised by Ian t o h beneficial and well appreciated by the at- Robson and Lars Lindberg Christensen P tendees. supported by Scientific and Local Organ- ising Committees. The work of the The conference summing-up was under- ‘FITS Liberator’ team was enormous in taken by Professor Paul Murdin (Cam- making the conference both success- Social event: Visit to bridge) who brought together the various ful and right up to the minute in terms of one of Munich’s many themes, tensions and links and additional- technology. Biergartens. Report on the ESO Workshop on Virtual Observatory Standards and Systems for Data Centres and Large Projects Paolo Padovani, Markus Dolensky (ESO) tion of common standards between data providers, tool users, and developers. These are being defined using new inter- The Virtual Observatory (VO) is an innova- national standards for data access ger 117, 58) and the logical next step tive, evolving system, which will allow and mining protocols under the auspices from AVO as a deployment of an opera- users to interrogate multiple data centres of the International Virtual Observatory tional VO in Europe (more on EURO-VO in a seamless and transparent way, to Alliance (IVOA: http://ivoa.net), a global in a future issue of The Messenger). best utilise astronomical data. New sci- collaboration of the world’s astronomical ence will be enabled, moving astrono- communities. At the European level, in Data centres lie at the foundation of the my beyond “classical” identification by addition to seven national VO projects, VO, as obviously access to astronomical allowing the characterisation of the prop- the European Community funded collabo- data at all wavelengths is a key require- erties of very faint sources by using all rative EURO-VO is the successor of the ment. The VO cannot (and does not) dic- the available information. The VO requires Astrophysical Virtual Observatory (AVO: tate how a data centre handles its own good communication, that is the adop- e.g., Padovani et al. 2004, The Messen- archive. All that is needed is a VO-layer 60 The Messenger 121 – September 2005 Group photo of the ESO workshop on Virtual Observatory Standards and Systems for Data Centres and Large Projects held from June 27 to July 1 at ESO Headquarters. O to “translate” any locally defined parame- S E , r ter to the standard (i.e., IVOA compliant) e y e H ones. For example, right ascension . H . can be identified in different ways but the H : o t VO user needs to know which of the o h many parameters accessible through an P archive interface is the right ascension. The longer-term vision of the VO is also to hide away any observatory/telescope/ instrument specific detail and work in as- tronomical units, for example, “wave- length range” and not grism or filter name. Data providers are then advised to sys- tematically collect metadata (“data about data”) about the curation process, assign unique identifiers, describe the general content (e.g., physical coverage) of a col- lection, and provide interface and capabil- ity parameters of public services. Finally, the VO will work at its best with high-level or “science-ready” data, and data centres should make an effort to provide such data. More specific lectures prepared the par- Finally, the data centre infrastructure tu- To get data providers started in most ticipants for two full days of hands-on tu- torial brought all of the above together of the above, the EURO-VO held a work- torials. Several software demonstrations and demonstrated a prototype framework shop at ESO Headquarters in Garching by various VO projects illustrated the cur- supporting the various formats, protocols from June 27 to July 1, 2005. The work- rent capabilities. and concepts. shop was explicitly designed for data cen- tres and large projects to acquire the The seven tutorials took place in parallel Judging from the participants’ feedback, knowledge and experience necessary to sessions and exercises were conduct- which was collected through a question- allow them to become “publishers” in ed on the participant’s own laptops. Up to naire, the workshop was considered “use- the VO. In tutorials and lectures, partici- 100 laptops were on-line through the ful” or “extremely useful” by 95 % of pants were instructed in the use of wireless Local Area Network (LAN), chal- the respondents. The tutorial material (see VO analysis tools, libraries, and the exist- lenging ESO’s excellent internal network below) is a collection of software which, ing web service infrastructure to build VO infrastructure without actually reaching its although still not in a final state, represents compliant services. The workshop was limits. The tutorials dealt with the follow- a unique and up-to-date snapshot of aimed at software engineers and design- ing topics: Data access layer, that is tools “state-of-the-art” VO technology. ers building archive interfaces, writing and protocols for sharing images and applications accessing remote data, or spectroscopic data; Astronomical Data The workshop agenda and contributions designing archive facilities and data flows Query Language (ADQL)/Skynode, which are available on http://www.euro-vo.org/ for future instruments and missions. is about accessing databases and pub- workshop2005. The tutorial software lishing catalogues; VOTable, the Extensi- was packaged and can also be accessed More than 120 participants, coming from ble Markup Language (XML) VO standard through FTP from the workshop page. 47 different institutions and 16 countries, format for the interchange of data, and It is mostly in Java and works on the most attended the workshop, with representa- the rich variety of tools and libraries to common platforms such as Linux, XP, and tives from 11 out of 15 IVOA members. support it; Metadata, that is how to tag Mac OS. concepts in Astronomy in a machine The workshop started with an overview of readable form using a defined vocabulary the EURO-VO project structure. An intro- called Unified Content Descriptors (UCD); duction on the current status of standard- Grid and web services, namely Informa- isation efforts and international IVOA tion Technology basics and how to set up working groups was then followed by a a service in order to share it on the lo- conceptual approach to the software cal network; Registries, which are places architectures available to publish data to where available resources such as as- the VO. tronomical data collections and software services are described. Participants learned how to set up such a registry as well as how to populate and search it. The Messenger 121 – September 2005 61.
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