ALMA Captures Unprecedented Image of Milky Way's Core
Astronomers using ALMA have produced the most detailed image to date of the Milky Way's Central Molecular Zone, revealing intricate gas filaments and detecting over 70 molecular species.
Astronomers utilizing the Atacama Large Millimeter/submillimeter Array (ALMA) have created the most detailed image to date of the Milky Way's Central Molecular Zone (CMZ), a dense and turbulent region surrounding the galaxy's supermassive black hole, Sagittarius A*. This image, spanning an area equivalent to three full moons, reveals a complex network of cold gas filaments and provides new insights into star formation processes in this extreme environment.
The CMZ contains about 80% of the Milky Way's dense molecular gas, yet it forms stars at a rate significantly lower than expected. The ALMA CMZ Exploration Survey (ACES) aims to understand this discrepancy by mapping the distribution and movement of gas within the region. The survey detected over 70 molecular species, including methanol, ethanol, and silicon monoxide, which serve as tracers for various physical and chemical processes.
"The CMZ hosts some of the most massive stars known in our galaxy, many of which live fast and die young, ending their lives in powerful supernova explosions, and even hypernovae," said Steve Longmore, ACES leader and professor of astrophysics at Liverpool John Moores University. "By studying how stars are born in the CMZ, we can also gain a clearer ... ."
The findings, published in the Monthly Notices of the Royal Astr ... , suggest that the extreme conditions in the CMZ—such as intense radiation, strong magnetic fields, and rapid orbital shear—may inhibit star formation by preventing gas clouds from collapsing into new stars. Understanding these processes in our own galaxy provides valuable insights into the behavior of distant, starbursting galaxies in the early universe.
The ACES project, involving over 160 scientists from 70 institutions worldwide, represents the largest image ever produced by ALMA. This comprehensive dataset will serve as a reference for future studies, guiding follow-up observations with other radio facilities and complementing infrared views of embedded stars provided by different observatories.