F. Genova, ERPANET/CODATA workshop, 2003/12/15

The astrophysicalVirtual ObservatoryFrom information networking

toinformation integration

Lisbon, December 15th, 2003

F. Genova, ERPANET/CODATA workshop, 2003/12/15

Why keeping data in astronomy?

• Long term observation of variable natural phenomena

• Major scientific objectives:

– Variability, evolution, statistics

– Observations with different techniques, at different scales

the physical phenomena at work

F. Genova, ERPANET/CODATA workshop, 2003/12/15

Large projects

• Large ground- and space-based observatories

• Large surveysOptimize the scientific return by increasing

usage

Same goals for earth sciences! observation networks are also large projects

F. Genova, ERPANET/CODATA workshop, 2003/12/15

Networking of information in astronomy

• A small discipline

• Few commercial constraints

• A long term partnership to define exchange standards and links

F. Genova, ERPANET/CODATA workshop, 2003/12/15

Networking of astronomical information

Observations

Ground- and space-based observatories

Surveys

Results

Publications in electronic journals

F. Genova, ERPANET/CODATA workshop, 2003/12/15

Property rights

• Observational dataIn general available after a proprietary period

(1 year)

• Journals– Table of contents and abstracts freely available– Full contents in general available after 3 years

F. Genova, ERPANET/CODATA workshop, 2003/12/15

The actors• Data producers

Know instruments and methods preserve ‘usable’ data and project memory

• Disciplinary centersData and information in a given domain

• JournalsResults

• Data CentersValue-added services and generic tools

F. Genova, ERPANET/CODATA workshop, 2003/12/15

NetworkingThe astronomy bibliographic network

Links between

– electronic journals – the NASA ADS bibliographic database– on-line services (SIMBAD, NED)– archival data

bibcode e.g. 1999A&A...351.1003G

F. Genova, ERPANET/CODATA workshop, 2003/12/15

ADS

From bibliographyTo the originalobservations

Search an author’s publications

F. Genova, ERPANET/CODATA workshop, 2003/12/15

Select a publication

F. Genova, ERPANET/CODATA workshop, 2003/12/15

F. Genova, ERPANET/CODATA workshop, 2003/12/15

Link to the ISO satellite data base

F. Genova, ERPANET/CODATA workshop, 2003/12/15

Data federationTabular data in astronomy

A common description for tabular data– Reference catalogues– Published tables– Surveys– Catalogues of observations in archives

ReadMephysical organization contents

F. Genova, ERPANET/CODATA workshop, 2003/12/15

F. Genova, ERPANET/CODATA workshop, 2003/12/15

An homogenized view of heterogeneous informationWith links to data

F. Genova, ERPANET/CODATA workshop, 2003/12/15

Lessons learnt

• De facto standards

• Cooperation between all the actors

+ snowball effectJournals, ADS, data centers, archive centers

• Easy-to-build link

but contents / validation are fundamental

better done by specialists from all partners

F. Genova, ERPANET/CODATA workshop, 2003/12/15

The Virtual Observatory

« an enabling and coordinating entity to foster the development of tools, protocols, and collaborations necessary to realize the full scientific potential of astronomical databases in the coming decade »

NVO White Paper, juin 2000

Science driven

F. Genova, ERPANET/CODATA workshop, 2003/12/15

The international Virtual Observatory Alliance

• Many VO projects in different countries (e.g. the European AVO RTD project)

• Each project has its own goals, depending on the project participants expertise and on the priorities of the funding agency (often IT money)

• All projects participate in the International Virtual Observatory Alliance (IVOA)

F. Genova, ERPANET/CODATA workshop, 2003/12/15

F. Genova, ERPANET/CODATA workshop, 2003/12/15

IVOA role

• Contact between the projects (regular telecons)

• A common roadmap: yearly demos• Intense activity on interoperability standard

definition (email, face to face meetings – 30 people in Jan. 2002, 130 in Oct. 2003)

• A International Astronomical Union WG to adopt the standards

F. Genova, ERPANET/CODATA workshop, 2003/12/15

F. Genova, ERPANET/CODATA workshop, 2003/12/15

F. Genova, ERPANET/CODATA workshop, 2003/12/15

F. Genova, ERPANET/CODATA workshop, 2003/12/15

F. Genova, ERPANET/CODATA workshop, 2003/12/15

Data access layer

• A common standard to describe astronomical images: FITS

(more than 30 years old)

• IVOA data access layer: Simple image access protocal

• On-going work on Simple spectral access protocol

F. Genova, ERPANET/CODATA workshop, 2003/12/15

A ‘flat’ data list

F. Genova, ERPANET/CODATA workshop, 2003/12/15

Data organization

A view of the IDHA data model developed for the AVO demo

Metadata at each level of the hierarchical data tree

F. Genova, ERPANET/CODATA workshop, 2003/12/15

Observations from European archives (AVO interoperability prototype)Inclusive: NASA missions HST, Chandra, surveys, …

F. Genova, ERPANET/CODATA workshop, 2003/12/15

The time dimension

** WNO 7

1951.8391987.7511995.653