The heart of the Milky Way is packed with 1,000 mysterious magnetic filaments, ten times more than previously thought, according to new radio observations made with the MeerKAT radio telescope at the South African Radio Astronomy Observatory (SARAO) in the Northern Cape province of South Africa. country, which reveal that astronomers were observing a small fraction of these filaments: there are at least 10 times more than previously known.
The strange threads, some stretching up to 150 light-years across, were first discovered by Northwestern University astronomers in the early 1980s, but new observations have not only proven that there are many more, but that they are very well organized, they appear in pairs and groups and some are evenly spaced like the strings of a harp.
What are these galactic filaments? What function do they have?
Identifying more strands will allow for extensive statistical studies that could allow them to unravel this puzzle, experts say, but perhaps they are cosmic ray electrons spinning the magnetic field at close to the speed of light. But what causes them is really a mystery.
“We have studied individual filaments for a long time with a myopic view. Now, we finally see the big picture: a panoramic view filled with a large number of filaments. Just examining a few filaments makes it hard to draw any real conclusions about what they are and where they came from. This is a milestone in improving our understanding of these structures”, explains Yusef-Zadeh, lead author of the paper published in The Astrophysical Journal Letters.
Yusef-Zadeh clearly exposes what this new finding in the heart of the galaxy means: “If you were from another planet, for example, and you met a very tall person on Earth, you could assume that all people are tall. But if you do statistics on a population of people, you can find the average height. That is exactly what we are doing. We can find the strength of the magnetic fields, their lengths, their orientations, and the radiation spectrum.”
It seems unlikely that the filaments are related to supernova remnants. They are more likely the product of Sagittarius A* , the supermassive black hole at the center of the galaxy. The astronomers were also able to verify that the magnetic fields along the filaments are amplified.
The team got this image we see after creating a mosaic of 20 separate observations of different parts of the sky in the direction of the galactic center , which is about 25,000 light-years from Earth.
Referencia: “Statistical Properties of the Population of the Galactic Center Filaments: The Spectral Index and Equipartition Magnetic Field” by F. Yusef-Zadeh, R. G. Arendt, M. Wardle, I. Heywood, W. D. Cotton and F. Camilo, Accepted, The Astrophysical Journal Letters.
arXiv:2201.10552
“The 1.28 GHz MeerKAT Galactic Center Mosaic” by I. Heywood, I. Rammala, F. Camilo, WD Cotton, F. Yusef-Zadeh, TD Abbott, RM Adam, G. Adams, MA Aldera, KMB Asad, EF Bauermeister, TGH Bennett, HL Bester, WA Bode, DH Botha, AG Botha, LRS Brederode, S. Buchner, JP Burger, T. Cheetham, DIL de Villiers, MA Dikgale-Mahlakoana, LJ du Toit, SWP Esterhuyse, BL Fanaroff, S. February, DJ Fourie, BS Frank, RRG Gamatham, M. Geyer, S. Goedhart, M. Gouws, SC Gumede, MJ Hlakola, A. Hokwana, SW Hoosen, JMG Horrell, B. Hugo, AI Isaacson, GIG Józsa, JL Jonas, AF Joubert, RPM Julie, FB Kapp, JS Kenyon, PPA Kotzé, N. Kriek, H. Kriel, VK Krishnan, R. Lehmensiek, D. Liebenberg, RT Lord, BM Lunsky, K. Madisa, LG Magnus, O Mahgoub, A. Makhaba, S. Makhathini, JA Malan, JR Manley, SJ Marais, A. Martens, T. Mauch, BC Merry, RP Millenaar, N. Mnyandu, OJ Mokone, TE Monama, MC Mphego, WS New, B. Ngcebetsha, KJ Ngoasheng, MT Ockards, N. Oozeer, AJ Otto, SS Passmoor, AA Patel, A. Peens-Hough, SJ Perkins, AJT Ramaila, NMR Ramanujam, ZR Ramudzuli, SM Ratcliffe, A. Robyntjies, S. Salie, N. Sambu, CTG Schollar, LC Schwardt, RL Schwartz, M. Serylak, R. Siebrits, SK Sirothia, M. Slabber, OM Smirnov, L. Sofeya, B. Taljaard, C. Tasse, AJ Tiplady, O. Toruvanda, SN Twum, TJ van Balla, A. van der Byl, C. van der Merwe, V. Van Tonder, R. Van Wyk, AJ Venter, M Venter, BH Wallace, MG Welz, LP Williams and B. Xaia, Accepted, The Astrophysical Journal Letters.
arXiv: 2201.10541
