Machine learning helps SA-led team 'see unexplained astronomical object'
Machine learning is helping a team of South African, US and Australian scientists better understand a rare “unexplained astronomical object” observed in space.
Scientists are still working out what a newly discovered class of radio sources, known as Odd Radio Circles (ORC), are and how they originated.
The team was led by Michelle Lochner, who holds a joint position at the University of the Western Cape (UWC) and the South African Radio Astronomy Observatory (Sarao).
They combed through data generated in the MeerKAT Galaxy Cluster Legacy Survey (MGCLS), a programme of observations of 115 galaxy clusters, run on South Africa’s MeerKAT Radio Telescope between June 2018 and June 2019, as reported on Monday in the publication Nature.
This led to the “seventh sighting” of what the team named Sauron — in keeping with a Lord of the Rings theme — which shares characteristics of an ORC but needs further study before it can be officially confirmed as one.
Only six confirmed sightings have been recorded, the first by the Australian Square Kilometre Array Pathfinder (Askap) in 2019.
“There is a good chance that scientists may have overlooked Sauron were it not for machine learning, which is essentially a set of algorithms that are designed to automatically learn patterns and models from available data. This bypasses the laborious and time-consuming work where because of human constraints, novel objects may go undetected,” said the publication.
While more is being learnt about ORCs, there are various schools of thought as to what they are, one being that they are normal radio galaxies observed from odd angles. Another attributes them to an intense period of star formation and a third views them as remnants of a huge explosion caused by the merger of supermassive black holes.
“Sauron could plausibly be the result of the enormous release of energy resulting from the rare merger of two of these ‘supermassive’ black holes,” suggests one of the team members, Lawrence Rudnick, Professor Emeritus at the University of Minnesota.
The team hope to secure more observation time on MeerKAT to further explore Sauron.
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