A treble clef written in colliding galaxies

A swirl of radio waves shaped uncannily like a treble clef has puzzled astronomers — it sits almost directly behind the Milky Way's plane, where our own galaxy's stars and dust block the view. Using NASA's Chandra X-ray Observatory with the German eROSITA telescope and Europe's LOFAR radio array, a team led by Andrea Botteon of Italy's National Institute for Astrophysics has now traced the shape to an outburst from a supermassive black hole, followed by two galaxy clusters — among the largest structures in the universe — in the process of merging.