This Is The Largest Radio Color Image Of The Milky Way Ever Assembled – And It's Gorgeous

Due to the audio medium of radio, we tend to associate radio waves with sound, but they are a type of light. Just like we can see different colors due to different wavelengths of visible light, we can also treat different wavelengths or frequencies of radio waves as different colors. Astronomers have now used that approach to create a spectacular view of our galaxy – the largest low-frequency radio color image of the Milky Way ever assembled – showing how it looks across a wide range of radio colors.

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Over a period of 18 months, Curtin University PhD student Silvia Mantovanini used a supercomputer to combine the data from two radio surveys, GLEAM and GLEAM-X, conducted at the Murchison Widefield Array (MWA) telescope located at Inyarrimanha Ilgari Bundara, in Western Australia. The new image has twice the resolution and is twice as big as the previous GLEAM map from 2019, and reaches 10 times the sensitivity. This incredible view has an enormous amount of data behind which will provide new insights into our galaxy.

“This vibrant image delivers an unparalleled perspective of our Galaxy at low radio frequencies,” Mantovanini said in a statement. “It provides valuable insights into the evolution of stars, including their formation in various regions of the Galaxy, how they interact with other celestial objects, and ultimately their demise.”

Mantovanini’s research focuses on supernova remnants, the expanding clouds of gas from exploding stars. Radio waves are the way to find them in abundance. Comparing the new radio view to a previous visible light image in the video above, it is immediately obvious where the supernova remnants are, looking like splotches all across the plane of the Milky Way.

“You can clearly identify remnants of exploded stars, represented by large red circles. The smaller blue regions indicate stellar nurseries where new stars are actively forming,” she explained.

It is not only supernovae we can see, though. There are so many new discoveries waiting to happen, thanks to this map, and astronomers will not have anything better to work with for at least a decade.

“Only the world’s largest radio telescope, the SKA Observatory’s SKA-Low telescope, set to be completed in the next decade on Wajarri Yamaji Country in Western Australia, will have the capacity to surpass this image in terms of sensitivity and resolution,” concluded Associate Professor Natasha Hurley-Walker.

The SKA observatory will be located in South Africa (SKA-Mid) and Australia (SKA-Low). The Australian site will contain 131,072 antennas shaped like Christmas trees across a distance of 74 kilometers (45 miles) that will continually monitor the whole sky. From that data, a new map even better than this will be created.

The study is published in Publications of the Astronomical Society of Australia (PASA).