published on 13 September 2019 in space
Bubbles of radio waves at the centre of the Milky Way
At the centre of the Milky Way there is a supermassive black hole called Sagittarius A*, which has captured the attention of an international group of astronomers from 15 different research institutions. An enormous hourglass-shaped structure that emits radio waves has been observed close to Sagittarius A*. This exceptional celestial structure, made up of two enormous bubbles that emit radio waves, measures hundreds of light years (that is millions of billions kilometres) and seems to be the result of an energetic outburst that took place millions of years ago close to this supermassive black hole in our galaxy. This discovery was made possible by the collection of data by the 64 parabolic antennas forming the MeerKAT network, distributed in the semi-desert Karoo region, in northern South Africa. The results of this research have been published in the scientific journal Nature.
As Ian Heywood of Oxford University, lead author of the research, has stated, “The centre of our galaxy is relatively calm when compared to other galaxies with very active central black holes. Even so, the Milky Way’s central black hole can become uncharacteristically active, flaring up as it periodically devours massive clumps of dust and gas.”
This discovery brings us increasingly closer to understanding the processes and phenomena that occur in the nuclei, including the more luminous ones, of outer galaxies like ours.