A massive infrared atlas of five nearby stellar nurseries was created by astronomers by combining more than a million images from the telescope European Southern Observatory VISTA.

These large “mosaics” reveal young stars in development, embedded in dense clouds of dust. Thanks to these observations, astronomers have a unique tool with which they can decipher the complex puzzle of star birth. “In these images we can detect even the faintest sources of light, such as stars much less massive than the Sun, revealing objects that no one has ever seen before,” says Stefan Meingast, an astronomer at the University of Vienna and lead author of the study, published in the journal Astronomy & Astrophysics. “This will allow us to understand the processes that turn gas and dust into stars,” he adds.

Stars form when clouds of gas and dust collapse under their own gravity, but the details of how this happens are not fully understood. How many stars are born from a cloud? How big is their mass? How many stars will have planets? To answer these questions the research team examined five nearby star-forming regions with the VISTA telescope in Paranal Observatory in Chile. Using VISTA’s infrared VIRCAM camera the team recorded the light coming from the deep interior of the dust clouds. The researchers observed star-forming regions in the constellations of Orion, Ophiuchus, Chameleon, South Stephanus and Lycus, which are less than 1,500 light-years away.

The team received more than a million images over five years. The images were then assembled into large mosaics that are published revealing vast cosmic landscapes. These detailed panoramas show dark dust specks, glowing clouds, newborn stars and the distant stars of our galaxy. Among other things, the data will allow astronomers to study how young stars move and how they leave their parent clouds.

The European Southern Observatory’s Extremely Large Telescope (ELT), under construction in Chile, “will allow us to focus on specific regions in unprecedented detail, giving us an unprecedented close-up of the individual stars that are now forming there,” concludes Meingast.