Third CALIFA data release: an inspiration to be curious about galaxies

11 April 2016. The Calar Alto Legacy Integral Field Area Survey (CALIFA) has released all of the data assembled over six years of work. The data of more than 600 galaxies are accessible for anyone interested at http://califa.caha.es/DR3. The astronomical community thus obtains free access to the largest dataset of spatially resolved properties of galaxies ever obtained.

CALIFA provides a unique way to learn about the evolution of galaxies. While we ourselves live in a specific galaxy, there are many more siblings of the Milky Way out there. A favourite analogy of the project Principal Investigator, Dr. Sebastian Sanchez (UNAM, Mexiko): “A social scientist would naturally learn much more about a specific human by studying her environment, her family and other social relations. Exactly in the same way can we astronomers support the understanding of our cosmic home, the Milky Way, by studying its siblings in the skies. Studying galaxies to learn about their evolution is a fascinating subject, because - just as humans - they come in a wide variety of appearances shaped by their specific evolutionary histories.”

CALIFA is the first project to apply the technique of integral field spectroscopy to a sample that represents all galaxies in the Local Universe, providing a panoramic view of galaxy evolution. Integral field spectroscopy is a technique that allows to determine the properties of galaxies at many different places of each galaxy, i.e. in a spatially resolved way. The CALIFA sample on the other hand was specifically selected to be representative of galaxies in the Local Universe. “We knew that some galaxy properties change systematically. But seeing this in such detail and for so many properties for which this was previously not possible is new and exciting. It provides new avenues to study galaxies and understand why exactly they turn out to be as they are” says Dr. Jakob Walcher from the Leibniz Institute for Astrophysics Potsdam (AIP), the Project Scientist of CALIFA. Data were obtained with the AIP-built integral-field spectrograph PMAS/PPak at the Calar Alto Observatory.

“As a publicly funded project we see it as our duty to make the data available to the public. This also allows anyone interested to reproduce and work with our results” adds Dr. Stefano Zibetti (INAF Arcetri, Italy), Quality Control responsible of CALIFA, and therefore fundamentally involved in making sure that the data meet all quality criteria and will be truly useful to the international community of scientists. Ruben Garcia-Benito (IAA, Spain), responsible for running many of the fundamental software pieces that turned observations from the telescope into ready-to-release data adds: "We hope that the nice images we produce can inspire even more people to be curious about the Universe in general and galaxies in particular.”

Caption: The figure shows how galaxy properties vary systematically with their stellar mass (i.e. the number of stars they contain) and the star formation rate (i.e. the number of stars they are newly making every year at the present time). It illustrates the power of CALIFA data to help understand the evolution of galaxies.

Find the 3rd CALIFA data release online.

 

Science contact: Dr. Jakob Walcher, jwalcher@aip.de

Media contact: Kerstin Mork, +49 331 7499-803, presse@aip.de

 

The key topics of the Leibniz Institute for Astrophysics Potsdam (AIP) are cosmic magnetic fields and extragalactic astrophysics. A considerable part of the institute's efforts aim at the development of research technology in the fields of spectroscopy, robotic telescopes, and e-science. The AIP is the successor of the Berlin Observatory founded in 1700 and of the Astrophysical Observatory of Potsdam founded in 1874. The latter was the world's first observatory to emphasize explicitly the research area of astrophysics. Since 1992 the AIP is a member of the Leibniz Association.