Galaxies are dynamic and heterogeneous, and hence time-consuming to study using a traditional spectrometer. This is where the Calar Alto Legacy Integral Field Area (CALIFA) survey excels. Using an integral field spectrograph, the 3.5-metre telescope at the Calar Alto Observatory collects light from 350 specific points within each of 600 local galaxies. Thus, just one exposure produces detailed information from various parts of a given galaxy.

Credit: © CALIFA-TEAM

The first data release covers the 151 galaxies pictured. Each pixel contains spectral information about a galaxy's activity (red when star formation is minimal, blue when it's extensive) and content, where brightness indicates the number of stars.