Farhad Yusef-Zadeh was observing the center of the Milky Way galaxy in radio waves, looking for the presence of faint stars, when he saw it: a spindly structure giving off its own radio emissions. The filament-like feature was probably a glitch in the telescope, or something clouding the field of view, he decided. It shouldn’t be here, he thought, and stripped it out of his data.
But the mystery filament kept showing up, and soon Yusef-Zadeh found others. What the astronomer had mistaken for an imperfection turned out to be an entire population of cosmic structures at the heart of the galaxy.
More than 100 filaments have been detected since Yusef-Zadeh’s first encounter in the early 1980s. Astronomers can’t completely explain them, but they have given them familiar labels, naming them after the earthly things they resemble: the pelican, the mouse, the snake. The menagerie of filaments is clustered around the supermassive black hole at the center of our galaxy. “They haven’t been found elsewhere,” says Yusef-Zadeh, a physics and astronomy professor at Northwestern University.
Their origins remained a mystery, too, until now.
New observations of the galactic center have revealed a pair of giant bubbles at the center of the Milky Way that give off radio emissions, according to recent research published in Nature. The bubbles stretch outward from the black hole and extend into space in opposite directions. The billowy lobes resemble the two halves of an hourglass, with the black hole nestled at its waist. And the filaments that Yusef-Zadeh discovered all those years ago are encased within.