The International Virtual Observatory (IVO) — an amalgamation of astronomical and astrophysical data from the world's best telescopes and detectors — is on track to start operations early next year.

Two hundred astronomers and government officials met in Garching, Germany, on 10–14 June to plan the collaboration, which would integrate the world's astronomy databases into a single seamless resource.

They agreed to create an International Virtual Observatory Alliance, comprising representatives of existing astronomy databases, to make joint decisions on the key technologies, common data and software standards to be used in the project.

The meeting's delegates were optimistic that the community may be ready to begin using prototypes of the databases by next January, says Catherine Cesarsky, director of the European Southern Observatory, which is based in Garching and operates telescopes in Chile.

The main components of the IVO are currently in development. About US$20 million has been allocated by the United States, Britain, the European Union and Canada over over the past six months to virtual observatories based on their own databases, and more projects are being planned in Australia, India, Russia and Germany. The IVO's challenge is to combine these into a single resource.

Advances in telescope design mean that new generations of γ-ray, X-ray, optical and infrared telescopes are coming online, generating data at vastly increasing rates.

Astronomical databases are doubling in size each year, points out Jeremiah Ostriker, an astrophysicist at the University of Cambridge, UK. He argues that the data can only be handled using new techniques for distributed, high-power computing.

Enthusiasm for the IVO reflects a profound shift in how astronomy works, with researchers moving from the study of specific objects through particular telescopes to the systematic surveying of entire swathes of the sky, along the lines of the Sloan Digital Sky Survey (see Nature 407, 557; 2000).

In this environment, astronomers say, the advantages of the IVO are manifest. The data it holds will be re-used by many research teams, for different purposes. For example, supernovae could be studied by correlating signals in astronomy databases with gravitational-wave data, as well as data from neutrino detectors in high-energy-physics databases.

The IVO will also democratize astronomy and astrophysics, adds Cesarsky, as scientists and amateur astronomers, who lack the resources to build and operate large observatories, will gain access to data from the world's best instruments and to sophisticated analysis tools.