The J-PAS Astronomical Project releases the first data from its mapping of the Universe

In the autumn of 2023, the Javalambre Astrophysical Observatory (OAJ) collected the first data for the J-PAS project (Javalambre Physics of the Accelerating Universe Astrophysical Survey). This initiative is designed to map a large portion of the sky and study the nature of the expanding Universe in detail. “It is a highly ambitious project, not only because of the scale of its objectives but also due to the technological and scientific innovations it incorporates, as well as the impact it will have on the study of the cosmos,” highlights José Manuel Vílchez, research professor at the Instituto de Astrofísica de Andalucía (IAA-CSIC) and member of the International Steering Committee of the collaboration.

One year later, the first images and catalogs from this international project have been released and are now available on its website. These data reveal the three-dimensional positions of 100,000 stars and approximately 450,000 galaxies, showcasing the first scientific demonstration of the potential of the wide-field JST250 telescope and its panoramic JPCam.

Mosaic generated from the data to be released. Credits: David Muniesa / CEFCA

AN UNPRECEDENTED MAP

The J-PAS mapping is the result of a unique combination: observing a large volume of the Universe in an unprecedented number of photometric bands. The JPCam camera integrates 56 narrow-band optical filters, unique on the international level and specifically defined for the project. In practice, this involves obtaining homogeneous multicolor information for all observed objects, enabling the determination of key astrophysical properties such as the temperature and composition of stars, the age or distance of galaxies, and more.

J-PAS is set to become the most complete photometric mapping of the Universe, as well as an international reference for a multitude of scientific applications. It will observe thousands of square degrees of the sky with hundreds of millions of galaxies and stars. ‘Any future study of these objects will benefit from the information provided by J-PAS. As a legacy project, we believe that J-PAS will become one of the major international references in astrophysics over the next decade. And this release is the first step on this path,’ says Dr Carlos López San Juan, deputy scientific director of CEFCA, an institution leading the project alongside the IAA-CSIC, the National Observatory of Rio de Janeiro, and the University of São Paulo.

INFORMATION IN EVERY PIXEL

J-PAS now opens access to the data corresponding to a total of 12 square degrees with the 56 filters of the project. The data set consists of 25,000 images that have been obtained over the last year. The J-PAS images are unique in that they provide information in all filters, but also in all pixels of the observed area. The images themselves are calibrated, which means that the light intensity can be measured at any point of any survey, in the 56 filters.

Professor Vílchez (IAA-CSIC) states that "this is a scientific milestone of great magnitude, marking the beginning of significant advancements in astrophysics, which will lead to new and fascinating discoveries in the coming years."

Hundreds of images are taken every night from the Javalambre Astrophysical Observatory (OAJ), which also require a dedicated data centre for their storage, management and calibration. The development of image processing tools is another milestone of the J-PAS project.

 Two clips from the mosaic that show relevant and outstanding areas. Credits: Jose Luis Lamadrid /CEFCA

ONE OF THE WORLD’S LARGEST CAMERAS

The J-PAS project began taking the first scientific images about a year ago. J-PAS is the main project carried out with the JST250 telescope, a 2.5 meter wide-angle telescope at the Javalambre Astrophysical Observatory (OAJ). Its scientific instrument is the Javalambre Panoramic Camera (JPCam) which, with more than 1.2 billion pixels, is currently one of the largest astronomical cameras in the world. The combination of JPCam and JST250 provides a uniquely powerful tool capable of mapping the Universe and measuring extragalactic distances with precision.

 Javalambre Survey Telescope (JST250) from the Observatorio Astrofísico de Javalambre and its scientific instrument, JPCam. Credit: CEFCA

J-PAS: AN INTERNATIONAL SCIENTIFIC COLLABORATION

It is led by the Centro de Estudios de Física del Cosmos de Aragón (CEFCA) and the Instituto de Astrofísica de Andalucía (IAA-CSIC), in Spain, and by the National Observatory of Rio de Janeiro and the University of Sao Paulo, in Brazil, and is developed and scientifically exploited through an international collaboration with more than 250 researchers from 18 countries.

J-PAS is a legacy project for the international scientific community that will offer a unique view of the Universe, both in terms of the type and the amount of information it will provide for each and every one of the hundreds of millions of astronomical objects it will systematically observe. 

"The release of these data represents a significant advancement for the entire scientific community, as they are 100% public and unique due to their broad spectral coverage and the vast area of the sky they cover. This will not only boost the science associated with J-PAS but will also provide valuable support for other ongoing research worldwide, which will be able to benefit from this contribution," concludes José Manuel Vílchez (IAA-CSIC).

The OAJ and the J-PAS Project are funded by the CEFCA and by the Governments of Aragon and Spain through the Teruel Investment Fund, the European Union within the framework of the Recovery, Transformation and Resilience Plan (NextGenerationEU) and the European Regional Development Funds. The Brazilian agencies FINEP, FAPESP, FAPERJ and the National Observatory of Brazil have contributed to the funding of JPCam. Additional funding for J-PAS has been provided by the Estonian Tartu Observatory and the Chinese J-PAS Astronomical Consortium.