Wonderful – and informative: Astronomers present new images of our neighboring galaxies in different colors, giving astronomers insights into the processes of star formation. The images give detailed insights into structures with particularly young stars as well as into the gas formations that heat them up around them. By combining them with other data, these observations can now provide new insights into which mechanisms stimulate matter to form stars, the scientists explain.
They are like the cities of the cosmos: In the galaxies, billions of stars and the matter surrounding them form complex structures through gravitational forces. It is generally known that the stars are born there in gas clouds, but there are still many questions about what triggers the stellar evolution and what role each galaxy as a whole plays. In order to gain insights, images of galaxies and their nurseries as complex as possible are necessary. A team of international astronomers is dedicated to this goal as part of the PHANGS (Physics at High Angular Resolution in Nearby GalaxieS) project. Now they are presenting some of our neighboring galaxies in an unprecedented level of detail and color.
Colorful insights
The scientists recorded the cosmic structures as a whole with powerful telescopes on the ground and in space and targeted specific regions in a targeted manner. The various observatories were selected so that the team could capture our galactic neighbors at different wavelengths. The color complexity highlighted different parts of the observed galaxies. The multi-unit spectroscopic explorer (MUSE) of the Very Large Telescope (VLT) of the European Southern Observatory (ESO) made it possible to take a close look at the galactic nurseries. Astronomers used this instrument to track down newborn stars and the warm gas around them. As they explain, this matter is illuminated and heated up by the stars and can thus provide clues to the processes of star formation.
“For the first time, we are now resolving individual star formation areas with a large variety of regions and environments in a selection of galaxies that represent the different variants well,” says co-author Eric Emsellem from ESO in Germany. The combination of data enables scientists to study the various stages of star formation far better than before. “With PHANGS, we have succeeded for the first time in developing a complete image that is sharp enough to see the individual clouds, stars and nebulae that indicate the formation of stars,” says co-author Francesco Belfiore from INAF -Arcetri in Florence.
An atlas of galactic nurseries
As part of the project, the researchers are also combining the new MUSE images with observations of the same galaxies that were recently created using the Atacama Large Millimeter / submillimeter Array (ALMA). These images are particularly well suited for mapping cold gas clouds – the objects in galaxies that provide the raw material for star formation. As the astronomers explain, the combination of the MUSE and ALMA images enables comparisons that can provide particularly revealing insights into what triggers, amplifies or dampens the birth of new stars.
The astronomers have already been able to map gas clouds in 90 nearby galaxies and thus create a previously unequaled detailed atlas of the stellar germ cells in the nearby universe. It can serve as the basis for further research: “There are many puzzles that we want to decipher,” says co-author Kathryn Kreckel from the University of Heidelberg. “Are stars more often born in certain regions of their host galaxies? And if so, why? And how does the development of these stars after their birth influence the formation of new generations of stars? ”Thanks to the wealth of new data, astronomers can now pursue these questions in a targeted manner.
The PHANGS team will now stay on the ball. “So far, the resolution of the maps we have created is sufficient to identify and separate individual star formation clouds, but it cannot yet clarify what is happening in them in detail,” says co-author Eva Schinnerer from the Max Planck Institute for Astronomy in Heidelberg. In this context, the scientists are now hoping for the expansion of the cosmic eyes of mankind: NASA’s James Webb Space Telescope and ESO’s Extremely Large Telescope (ELT) will soon enable even more detailed views of the structures of star formation areas. “We have decades of exciting discoveries ahead of us,” Schinnerer concludes.
Caption: Examples of five galaxies recorded as part of the PHANGS project. (Image: ESO / PHANGS)
Source: ESO, PHANGS website