Astrophysicist Farhad Zadeh provides new hypothesis for magnetic filaments in the Milky Way

Large-scale magnetic filaments spill downward from a black hole's jet, located in a distant cluster galaxy. Credit: Rudnick and collaborators, 2022( Northwestern Now)

Northwestern University astrophysicist Farhad Zadeh has been fascinated and puzzled by a family of large-scale, highly organized magnetic filaments dangling in the center of the Milky Way ever since he first discovered them in the early 1980s.

Now, 40 years later, Zadeh remains just as fascinated — but perhaps slightly less puzzled.

With a discovery of similar filaments located in other galaxies, Zadeh and his collaborators have, for the first time, introduced two possible explanations for the filaments’ unknown origins. In a new paper, published earlier this month in The Astrophysical Journal Letters, Zadeh and his co-authors propose the filaments might result from an interaction between large-scale wind and clouds or could arise from turbulence inside a weak magnetic field.

“We know a lot about the filaments in our own Galactic Center, and now filaments in outside galaxies are beginning to show up as a new population of extragalactic filaments,” Zadeh said. “The underlying physical mechanisms for both populations of filaments are similar despite the 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 very distant (in time and space) cousins.”

An expert in radio astronomy, Zadeh is a professor of physics and astronomy at Northwestern’s Weinberg College of Arts and Sciences and a member of the Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA).

Continue reading in Northwestern Now’s story, “The Milky Way’s mysterious filaments have ‘older, distant cousins.’”