We are closer to solving the mystery of hundreds upon hundreds of filaments. Through the heart, danglingThe Milky Way
These long, magnetic filaments that glow in radio waves were seen for the first time from other galaxies. They are not only no longer limited to the Milky Way; scientists can also find them in a variety of environments, which allows them to be studied more closely.
Farhad Yusuf-Zadeh, an American astronomer, discovered the Milky Way’s filaments during the 1980s. He has been puzzled over them since then.
Yusuf Zadeh suggests that there are two explanations. One is interaction between large clouds and galactic winds; the other is turbulence in weak magnetic fields caused by galaxies’ motion.
“We now know a lot more about the filaments within our Galactic Center. But filaments outside of galaxies have begun to show up as an additional population of extragalactic filaments.” Yusuf-Zadeh says.
“The physical mechanisms that underlie both populations of filaments are identical despite their vastly different environments. The objects are part of the same family, but the filaments outside the Milky Way are older, distant cousins – and I mean VeryThey are distant cousins (in both time and space).
Nearly 1,000 filaments measuring 150 light-years long and hanging in oddly ordered arrangements such as harp strings have been found in the Milky Way. This discovery was made most recently by the MeerKAT radio telescope in South Africa.
The telescope’s sensitive observations of the galactic center – penetrating through the thick dust and gas that obscures much of what’s inside – Expanded the number filamentsThe factor of ten was known before. These radio observations also showed that the filaments contained cosmic-ray electrons moving in magnetic fields at nearly the speed light travels. The magnetic fields are amplified along their entire length.
It was difficult to figure out why these filaments were there, just quietly in the galactic centre, without more information. This is a significant breakthrough in the discovery of filaments in four different galaxy clusters located between 163 million to 652 million light years away.
“After all these years of studying filaments in the Galactic Center, I was thrilled to see these incredible structures.” Yusuf-Zadeh says. “Because these filaments were found elsewhere in the Universe it suggests that something universal may be happening.”
In several important ways, the filaments discovered outside of our Milky Way are distinct from the thread-like structures found in our galaxy. They are also associated with the lobes and jets. radio galaxies – huge structures that erupt from the galactic center, extending vast distances on either side of the galactic plane. The filaments that extend from these jets and lobes are also far larger than the structures seen in the Milky Way’s center – between 100 and 1,000 times larger.
“Some have incredible lengths, up to 200 Kiloparsecs,” Yusuf-Zadeh says.
“This is four or five times the size of the whole Milky Way. Their electrons are able to stay together on a very large scale, which is quite remarkable. It would take 700,000. years for an electron to travel at the speed light along the length of the filament. They don’t travel at light speed.
They are also older and have weaker magnetic fields. They also extend into intergalactic space at right angles to the jets. The galactic disk appears to be the center of the Milky Way’s filaments.
However, there are many similarities. The length-to-width ratio of extragalactic and gallactic filaments is identical, as well as the cosmic ray transport mechanism. The same mechanism that produces all filaments must work on different scales if it is to succeed.
One such mechanism could be wind. Active supermassive Black holesGalactic winds can be generated by star formation and can gust out into intergalactic spaces. These winds could push into interstellar or intergalactic clouds of dust and gas, pushing material together to form filamentary structures.
Simulations indicated another possibility: turbulence within the medium, caused by gravitational disruptions. This turbulence may cause eddies within the intergalactic medium. In this case, weak magnetic field can be snagged around it, folded and then stretched out to form filaments with strong magnet fields.
It’s not a definitive answer – yet. We don’t know if both types of filaments are controlled by the same mechanism, or if different phenomena can create structures that appear uncannily similar.
“All of these filaments that are not in our galaxy are very ancient,” Yusuf-Zadeh says.
“They seem to be from a different time in the Universe, but they signal the Milky Way inhabitants that the filaments formed from the same source.” This is amazing, I think.”
The research was published in The Astrophysical Journal Letters.
