The universe is full of magnetic fields. Even though the universe is electrically neutral, atoms can ionize into positively charged nuclei and negatively charged electrons.
When these charges are accelerated, they create a magnetic field. One of the most common sources of magnetic fields on large scales comes from collisions between and within interstellar plasma. It is one of the main sources of magnetic fields for magnetic fields on a galactic scale.
But magnetic fields must also exist on a larger scale. On the largest scales of the universe, matter is distributed in structures known as cosmic webs. Large clusters of galaxies are separated by a barren void, like clusters of soapy water between large regions of soap bubbles. Thin filaments of intergalactic material stretch between these giant clusters, forming webs of cosmic matter.
Most of this lattice is ionized, so it must create a broad but faint intergalactic magnetic field. At least that’s the theory. Astronomers have not been able to observe this magnetic field on the Internet. But New study He made their first discovery.
We cannot directly detect magnetic fields billions of light years away. Rather, we observe it through its effect on charged particles. When electrons and other particles orbit along magnetic field lines, they emit radio light.
By mapping these radio signals, astronomers can map the galaxy’s magnetic field. But the threads of the cosmic web are scattered in such a way that the radio light they emit is extremely dim. Too faint to detect easily. And because nearby galaxies make stronger radio signals, web signals can be drowned out by the galaxy’s radio noise.
To overcome this challenge, the team focused on polarized radio light. These are radio emissions that have a specific orientation. Because its direction is related to the general direction of the filament, the team could easily pull this signal from the cosmic radio background.
They used data from sky radio maps such as the Global Magneto-Ionic Medium Survey, the Planck Legacy Archive, the Owens Valley Long Wavelength Array, and the Murchison Widefield Array. By collating this data and comparing it to a webcomic map, the team confirmed the polarized radio signal emitted by the webcomic.
This discovery is not only the first detection of magnetic fields in cosmic webs, but is also strong evidence supporting the existence of impact shock waves within intergalactic filaments.
These shock waves have been seen in computer simulations of cosmic structures, but this is the first evidence to support the idea that these simulated features are accurate.
This article was originally published by the universe today. Reading Original article.
