Calar Alto, the main astronomical observatory in continental Europe, has been a reference centre for international astronomy during the last decades. The quality of its skies and its excellent instrumentation have led to dramatic achievements in many research fields, from extrasolar planets to the exploration of the primordial universe.
Along its working life, that begun in 1975, Calar Alto has observed many thousands of celestial objects. This data volume will increase in the short run, when the new instruments now in phase of development will start making science. All this invaluable scientific information builds up a unique legacy that requires developing new archiving systems to guarantee an optimal exploitation of its potential.
From 2008 the German-Spanish Astronomical Centre (CAHA) and the Centre for Astrobiology (CAB) have been designing, developing and implementing all the infrastructure needed for such a demanding service as a scientific data archiving system. The system is made from two pieces, one placed at the Observatory itself and another located at CAB.
The staff of the German-Spanish Astronomical Centre (dependent on the Spanish CSIC and the German Max Planck Siciety, MPG) has fully developed the system placed at Calar Alto. In words of Enrique de Juan, the computer scientist in charge of this project, the basic principles are ”huge data storing capacity, easy enlargement and redundance for an improved reliability.” He stresses, too, that ”the software is easily scalable, specially keeping in mind the needs that may arise with the arrival of new astronomical instrumentation.” A complex combination of software and hardware gather all the data obtained at the Observatory each night. After that, the information is evaluated, classified and archived in a data base. This way, the scientists who own the data and that build their research on them can access the information with unprecedented flexibility, easiness and security.
Once a certain time lapse has passed, the data are no longer the exclusive propriety of the scientists responsible for the original observing proposals and, then, the archiving system placed at Calar Alto makes them public on the one hand and, in the other hand, it automatically transfers them, through a secure connection, to CAB.
The system placed at the Centre for Astrobiology (dependent on the Spanish Higher Council for Scientific Research, CSIC, and the National Institute for Aerospace Technology, INTA) performs a series of quality tests on the observational data, to guarantee its integrity and coherence, before feeding it into a scientific archiving system that fulfils all the requirements of the Virtual Observatory standards (VO). The Virtual Observatory is an international initiative in which Spain is taking part from 2004. Its main objective is granting an efficient access and powerful analysis tools for the huge mass of data existing in astronomical archives. Enrique Solano, in charge of this project at CAB, states that ”this archive we are presenting now will have a significant impact on the exploitation of Calar Alto data because, from one side, all the community will be able to use the information contained and, from the other side, its integration into VO will allow an efficient comparison with data coming from other archives around the world, what makes possible research projects that would be extremely difficult to perform outside VO.”
Calar Alto archives will make the data universally accessible after the initial reserve period for the authors of the observing proposals. This means that all the society (and not only professional astronomers, but also researchers from other fields, amateur astronomers, educators and general public) will be able to use the deep richness produced thanks to the exceptional sky and the outstanding telescopes and instruments of Calar Alto.
The scientific data archives of Calar Alto Observatory have been developed at the German-Spanish Astronomical Centre (CAHA, CSIC-MPG) and at the Centre for Astrobiology (CAB, INTA-CSIC). The project has been partially funded by the Ministery for Science and Education through the R+D+i 2008-2009 National Plan, and through the National Plan for Singular Scientific-Technical Facilities (ICTS).
© Calar Alto Observatory, September 2011