Oxford University | 2019 Sep 11
An international team of astronomers including members from the University of Oxford, has discovered one of the largest features ever observed in the centre of the Milky Way: a pair of enormous radio-emitting bubbles that tower hundreds of light-years above and below the central region of our galaxy.Bubbles of radio waves spotted at the centre of the Milky Way.
Credit: South African Radio Astronomy Observatory (SARAO)
Published in Nature today, scientists have shown how this hourglass-like feature, which dwarfs all other radio structures in the Galactic Centre, is likely the result of a phenomenally energetic burst that erupted near the Milky Way’s supermassive black hole a few million years ago.
Using the South African Radio Astronomy Observatory (SARAO) MeerKAT telescope, Ian Heywood of the University of Oxford’s Department of Physics and his colleagues mapped out broad regions in the centre of the galaxy, conducting observations at wavelengths near 23 centimetres. Radio emission of this kind is generated in a process known as synchrotron radiation, in which free-floating electrons are accelerated as they interact with powerful magnetic fields. This produces a characteristic radio signal that can be used to trace energetic regions in space. The radio light seen by MeerKAT penetrates the dense clouds of dust that block visible light from the centre of the galaxy. ...
By examining the nearly identical extent and morphology of the twin bubbles, the scientists believe they have found convincing evidence that these features were formed from a violent eruption that over a short period of time punched through the interstellar medium in opposite directions. ...
MeerKAT Discovers Giant Radio Bubbles at Center of Milky Way
South African Radio Astronomy Observatory (SARAO) | 2019 Sep 11
Giant Balloon-Like Structures Discovered at Center of Milky Way
Northwestern University | via EurekAlert | 2019 Sep 11
Giant ‘Bubbles’ Spotted around Milky Way’s Black Hole
Nature News | 2019 Sep 11
Inflation of 430-Parsec Bipolar Radio Bubbles in the Galactic Centre by an Energetic Event ~ Ian Heywood et al
- Nature 573(7773)235 (12 Sep 2019) DOI: 10.1038/s41586-019-1532-5