How does galaxy location drive galaxy structure and star formation? This is what a recent study published in the Monthly Notices of the Royal Astronomical Society hopes to address as a team of scientists investigated the interaction between galaxy location and evolution. This study has the potential to help scientists better understand galaxy formation and evolution, including stars and planets within them.
For the study, the researchers conducted the first study with the Deep Extragalactic Visible Legacy Survey (DEVILS) survey using the Anglo-Australian Telescope’s AAOmega spectrograph, the latter of which is located at Siding Spring Observatory in Australia. The goal of the study was to use DEVILS to add to the existing catalog of galaxy populations based on their speed traveling away from us, also known as redshift. In contrast, blueshift happens when an object is moving towards us.
In the end, the researchers found that galaxies that are clustered together, or more densely packed, result in slower growth and evolution compared to galaxies that are spread apart. The researchers used the analogy of city centers compared to more rural areas. Essentially, a galaxy’s location potentially determines its evolutionary fate.
“Our upbringing and environment influence who we are,” said Dr. Luke Davies, who is an assistant professor at The University of Western Australia and lead author of the study. “Someone who has lived their whole life in the city may have a very different personality compared to someone who lives remotely or in an isolated community. Galaxies are no different.”
Going forward, the researchers aspire to use this study as a foundation for better understanding the number of stars within a galaxy, along with star formation and evolution, in both the present and ancient universe. Billions of years ago, the entire universe was far more compact than it is today, meaning galaxies were closer together. However, as the universe expanded, galaxies became more dispersed, potentially enabling enhanced growth, along with enhanced star formation and evolution.
“DEVILS forms the basis of our future plans in exploring this key area of astrophysics research,” said Dr. Davies. “DEVILS has given us a detailed picture of galaxy evolution and next year, we will start collecting data for WAVES (Wide Area VISTA Extragalactic Survey). WAVES will allow us to significantly expand the number of galaxies and environments we study, plus help us build an even clearer picture of how the Universe came to look the way it does today.”
Our galaxy, the Milky Way, is estimated to be approximately 100,000 light-years in diameter, and is known as a barred spiral galaxy. Other galaxy types include elliptical, spiral, lenticular, irregular, dwarf, merging, and active galactic nucleus (AGN). It is hypothesized that a galaxy type is an indicator for its evolutionary history, as regions exhibiting high densities of galaxies resulting in certain galaxy types morphing into other types. For example, spiral galaxies could evolve into elliptical or lenticular galaxies over time. Therefore, studies like this could help scientists constrain galaxy formation and evolution based on their environment, specifically regarding how close they form to each other. This also includes the stars and planets that form and evolve within them.
This study comes as NASA’s powerful James Webb Space Telescope (JWST) continues to teach astronomer new findings regarding galaxy formation and evolution, specifically in the early universe. For example, while the universe was much more compact than it is today, JWST discovered that large galaxies formed much sooner than previously thought, along with black holes, of which supermassive black holes comprise larger galaxies like our own, could have formed much earlier than previously thought, too.
What new insight into galaxy location and evolution will researchers make in the coming years and decades? Only time will tell, and this is why we science!
As always, keep doing science & keep looking up!
Sources: Monthly Notices of the Royal Astronomical Society, EurekAlert!, ICRAR, arXiv
Featured Image Credit: The DEVILS team - ICRAR
