Intergalactic magnetism runs deep and wide

Hunting for magnetic energy in intergalactic space, researchers have found an unexpected motherlode of it. Both in the gaps between galaxies that are clustered and in the lonelier neighborhoods outside those clusters, magnetic fields are remarkably strong, a scientific team reports.

Computer-enhanced radio sky near the Coma cluster (arrow) shows intergalactic magnetic fields (red, weakest; blue, strongest) and more distant radio sources (compact blue dots).