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The galactic center with color-coded position angles of all filaments
Photo: Farhad Yusef-Zadeh / Northwestern University
"It was a surprise to suddenly find a new population of structures that seem to point in the direction of the black hole," says Farhad Yusef-Zadeh of Northwestern University in Evanston, Illinois. U.S. astrophysicists have discovered hundreds of filaments in the center of the Milky Way that were previously unknown. The study has now been published in The Astrophysical Journal Letters.
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The filaments are gigantic, one-dimensional threads located near our galaxy's central supermassive black hole, Sigattarius A*. In the 1980s, Yusef-Zadeh and his colleagues first discovered structures that are vertical to the black hole. Last year, he and colleagues reported nearly 1000,<> vertical filaments in further studies.
The structures in the newly discovered population are one-dimensional just like the previously known ones and can be observed with radio waves. But they are much shorter, about five to ten light-years long instead of 150 light-years. And they do not stand vertically, but horizontally or radially to the galactic plane, spreading like the spokes of a wheel from the black hole.
According to the research of Yusef-Zadeh and his collaborators, the filaments are not random. "We believe that they must have been caused by some kind of runoff from an activity that took place a few million years ago," says Yusef-Zadeh. "It seems to be the result of an interaction of this escaping material with objects in its vicinity." But work on the newly discovered structures has only just begun.
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