Using the world’s largest radio telescope array, The Atacama Large Millimeter/submillimeter Array, astronomers have dived deeper into the turbulent and complex tendrils of gas and dust at the heart of our galaxy than ever before.
“It’s a place of extremes, invisible to our eyes, but now revealed in extraordinary detail,” team member Ashley Barnes of the European Southern Observatory (ESO) said in a statement. “It is the only galactic nucleus close enough to Earth for us to study in such fine detail.”
The CMZ is packed with an intricate network of dense and cold gas that flows along filaments, often collapsing into clumps of matter that are capable of forming stars. Though this process can also happen at the edge of our galaxy, the process is far more extreme in the CMZ.
As part of ACES (the ALMA CMZ Exploration Survey), the team was able to determine the chemical composition of this molecular gas, detecting dozens of different molecules. These ranged from complex organic molecules like methanol and ethanol to simple molecules like silicon monoxide.
“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 hypernovas,” ACES leader and John Moores University researcher Steve Longmore explained in the statement. “By studying how stars are born in the CMZ, we can also gain a clearer picture of how galaxies grew and evolved.
“We believe the region shares many features with galaxies in the early universe, where stars were forming in chaotic, extreme environments.”
The CMZ is around the size of three full moons in the night sky, meaning even ALMA, composed of 66 radio antennas across the Atacama Desert regions of northern Chile, couldn’t image it all at once. Representing the largest area that ALMA has ever observed, the resultant image was basically stitched together using smaller, individual observations.
“We anticipated a high level of detail when designing the survey, but we were genuinely surprised by the complexity and richness revealed in the final mosaic,” ALMA astronomer Katharina Immer said in the statement.
The ACES research was published on Wednesday (Feb. 25) in the journal Monthly Notices of the Royal Astronomical Society.
