Astronomers have long known that galaxies grow and change over billions of years, but new results from a major international project show that where a galaxy lives in the universe has a powerful influence on how it evolves.
The Deep Extragalactic Visible Legacy Survey—better known as DEVILS—has released its first major set of findings, revealing how a galaxy’s surroundings can shape its size, appearance and even its ability to form stars.
The DEVILS project, led by Associate Professor Luke Davies from the International Center for Radio Astronomy Research (ICRAR) at The University of Western Australia, represents nearly a decade of planning, sky observations and intricate data analysis.
The team combined information from numerous ground- and space-based telescopes to create one of the most detailed surveys ever conducted of galaxies up to five billion years old.
Unlike earlier surveys, which focused mainly on big-picture trends in galaxy evolution, DEVILS zooms in on the fine details of the cosmic landscape.
Professor Davies says the team can now chart the “mountains, valleys and plateaus” of the universe—small-scale structures that strongly influence how galaxies grow.
In contrast, previous surveys could only map the broad “oceans and continents” of the cosmos, missing the more precise environmental effects.
By studying hundreds of thousands of galaxies, the DEVILS team discovered strong links between a galaxy’s environment and its behavior. Galaxies in crowded regions—where many galaxies cluster closely together—tend to grow more slowly.
They also have different shapes and structures compared to galaxies that live in more isolated, quiet parts of the universe.
Just as living in a busy city shapes a person differently than growing up in a remote rural town, galaxies develop differently depending on their surroundings.
In these crowded cosmic “city centers,” galaxies interact with one another and compete for gas, the raw material needed to form stars.
This competition can strip galaxies of fuel and slow down or even shut off star formation earlier than expected. When a galaxy stops producing new stars, astronomers say it has “died.”
The new DEVILS data allows researchers to examine how many stars a galaxy contains, how quickly it is forming new ones and how its structure and appearance have changed over time.
By comparing today’s galaxies with those that existed billions of years ago, scientists gain a clearer picture of how the universe has evolved.
The project’s public data release means scientists worldwide can now use DEVILS to explore their own questions about cosmic evolution.
And the work is far from finished. Associate Professor Davies and his team are preparing for the next major phase: the Wide Area VISTA Extragalactic Survey, or WAVES. This new survey will study even more galaxies across a wider range of environments, offering an even sharper view of how the universe came to look the way it does today.
The DEVILS research marks a major step forward in understanding why galaxies grow, change and sometimes fade—revealing that, just like people, galaxies are shaped by the company they keep.
Source: KSR.
