[Image: From “Probing Cosmic-Ray Transport with Radio Synchrotron Harps in the Galactic Center,” by Timon Thomas, Christoph Pfrommer, and Torsten Enßlin.]
The above image, as described by Susanna Kohler over at AAS Nova, depicts an ultra-large-scale magnetic “harp” near the center of our galaxy, emitting radio waves. The black lines apparently “span several light-years.”
As Kohler writes, where the parenthetical comments are her own, “a team of scientists argues that this cosmic music is caused by a massive star or a pulsar (a magnetized neutron star) plunging through an ordered magnetic field in the galactic center. As the star crosses (moving upward, in the image above) bundles of field lines, it discharges high-energy cosmic rays that travel in either direction along the bundles, emitting radio waves.”
It’s a kind of cosmic theremin—an instrument where the “musician controls volume and pitch using her hands to interfere with electromagnetic fields generated by the device”—a huge and ancient instrument playing itself in space.