Scientists have discovered the largest known structure that is active in the radio frequency range. It surrounds the galaxy cluster PLCK G287.0+32.9. An active region of such a large size challenges current ideas about radio physics.
PLCK G287.0+32.9 galaxy cluster
Scientists have discovered the largest structure in the Universe that emits radio waves. They announced this at the 246th meeting of the American Astronomical Society. We are talking about a huge gas and dust shell surrounding the galaxy cluster PLCK G287.0+32.9.
The cluster is located 5 billion light-years away from us and attracted the interest of scientists when it was discovered in 2011. This is not surprising, given that several massive galaxies are concentrated in a relatively small space, surrounded by two gas and dust relics — arcs that are traces of shock waves from the collision.
That is why scientists decided to study PLCK G287.0+32.9 not only in the radio range, but also using the Chandra X-ray telescope. They expected to see several point sources of radiation coinciding with the most intense parts of the shock waves. This would be logical, since interstellar gas emits intensively where it is more heated.
Record-breaking radio structure
Imagine how surprised the scientists were when they saw that the entire area between two shock waves, which were spreading in different directions, was emitting radio waves and that a cluster of galaxies was located between them. After all, it is about 20 million light years across. By comparison, the distance from the Andromeda Galaxy to the Milky Way is only 2 million light years.
Previously, the area around the Abell 2255 galaxy cluster was considered the record holder, but it is only 16.3 million light-years in size. Moreover, it turns out that inside the radio bubble around PLCK G287.0+32.9 there is an area measuring 11.4 million light-years across in which radio emissions are detected even at a frequency of 2.4 GHz.
The last fact is really important because radio emissions at such a frequency and on such a large scale are not usually detected. Something had to heat the gas on such a gigantic scale. Scientists suspect that this is somehow related to the fact that within the giant collision of galaxies, another collision of much more modest proportions took place.
According to phys.org
