(ORDO NEWS) — Astronomers usually use the Milky Way to learn about the properties of galaxies in general because it is the only galaxy whose processes we can study up close.
Given the Milky Way’s low star formation efficiency, you might think that high-yield star formation is one area where this method doesn’t work.
But you are wrong: the core of our galaxy is as efficient as the super-productive galaxies 10 billion years ago.
When studying star formation in the central regions of the Milky Way, a problem arises: the center of the galaxy is so crowded with stars that it is difficult to distinguish one star from another.
With the problem of crowding, scientists are faced with the question of the location of young stars.
Prior to the new analysis, astronomers were only able to detect about 10% of the expected total stellar mass at the center of the galaxy.
The scientists conducted the GALACTICNUCLEUS study, which used the HAWK-I infrared camera on the Very Large Telescope (VLT) to capture nearly 150 images of the Milky Way’s central region.
In order to identify individual stars in the crowded region, the scientists used a holographic imaging technique.
When the researchers examined the images, they found that the Sagittarius B1 region at the center of the galaxy was different from the rest.
It contains significantly more young stars that ionize the surrounding gas than in other regions.
Thanks to the observations of GALACTICNUCLEUS, for the first time, scientists have been able to study the stars in this region in detail.
Astronomers were only able to study giant stars, but the data on the 3 million stars they were able to study already contained a huge amount of information.
In particular, astronomers were able to determine the luminosity and brightness of each star.
When the scientists analyzed the luminosity distribution, they found that there were several phases of star formation in Sagittarius B1: an older population that formed between 2 and 7 billion years ago, and a large population of young stars that are only 10 million years old or even less. The young stars discovered have a total mass of over 400,000 solar masses.
In the inner regions of the galactic center there are stars older than 7 billion years, but there are practically no stars in the intermediate age range from 2 to 7 billion years.
This may indicate that star formation began in the inner region and then spread to the outer regions.
The scientists plan to continue their observations with the VLT. In the present study, conclusions were drawn based on the overall luminosity distribution.
Spectral observations would allow astronomers to identify some of the very young stars directly from the appearance of their spectra. This would be a good cross-check of currently published results.
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