The Milky Way is a decently big Galaxy. At 100,000 light years across, it is a full size barred spiral galaxy and distinctly different from what we would call ‘dwarf galaxies.’ But there are much larger galaxies in the universe. Most reside near the centre of a massive galaxy cluster and are the result of Billions of years of mergers and collisions. But some appear large because of their incredibly powerful release of energy. A new Galaxy discovered in the early universe by a team of astronomers from the National Centre for Radio Astrophysics is an incredible 4 million light years across, 40 times the width of the Milky Way!
The image above shows an optical field with the giant radio emission lobes highlighted in red. The Galaxy is part of a very rare group of galaxies known as ‘Giant Radio Galaxies.’ This particular galaxy is 9 Billion light years away, making it part of a very elite group discovered in the early universe.
The accepted theory at this point is that the super massive black hole at the centre of this galaxy is producing huge jets of emission due to the conservation of angular momentum. These jets extend far beyond the galaxy’s true borders, and cause the massive lobes of radio emission seen in the image.
In some cases, the massive black hole may stop producing the jets of material, for a handful of reasons. The result is that the lobes slowly fade away due to loss of energy. With this galaxy, known only as J021659-044920, we may be witnessing this dying period.
Understanding these giant torrents of energy give us an idea of the extreme possibilities of the universe. When we can catalogue the extremes of nature we can place constraints on what nature can do, and use these limits to test our theories of Physics. Ultimately our hope is to have a better understanding of the large-scale physics of the universe, from the big bang to the far distant future.