Something strange is sending radio waves from the centre of the galaxy

Illustration of radio waves emanating from the galactic center Sebastian Zentilomo
Strange radio signals are being sent from the center of the galaxy in the direction of the centre. We aren't sure what they are. They seem to turn on and off at will, and the source is unlike any other we have ever seen.

After Ziteng Wang, an Australian University student who discovered radio waves in Australia's University of Sydney, the source of the radiation was nicknamed Andys object. The emissions were spotted six times by he and his colleagues using the Australian Square Kilometre array Pathfinder radio telescope. Further observations were made using the MeerKAT radio telescope from South Africa.

Researchers discovered that while the object flared occasionally for a few weeks, it was mostly dark the majority of the time. After months of searching for it, it finally came back to life in February 2015. David Kaplan, University of Wisconsin-Milwaukee's part of the research team, said that they had looked at all wavelengths.


It was not visible at other wavelengths so it was impossible to explain.

Whatever Andy's object may be, the polarization of radio waves from it suggests that it has a strong magnet field. Its brightness changed by as much as 100 during flares. Flares also faded extremely quickly, which suggests that the object is small.

None of the astronomical bodies we know of can match all these strange characteristics. Kaplan says it is an intriguing object that defies explanations. This object could be part of a well-known class, or just a strange example. However, it will challenge our assumptions about how these classes behave.

Journal reference: The Astrophysical Journal, DOI: 10.3847/1538-4357/ac2360

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