Two `dancing` black holes sighted at heart of remote galaxy

Washington – Astronomers using NASA’s Wide-field Infrared Survey Explorer (WISE) have spotted what appears to be two supermassive black holes, at the heart of a remote galaxy, circling each other like dance partners.

Follow-up observations with the Australian Telescope Compact Array near Narrabri, Australia, and the Gemini South telescope in Chile revealed unusual features in the galaxy, including a lumpy jet thought to be the result of one black hole causing the jet of the other to sway.

Lead author Chao-Wei Tsai of NASA’s Jet Propulsion Laboratory, Pasadena, California, said that they think that the jet of one black hole is being wiggled by the other, like a dance with ribbons.

The new study took advantage of previously released all-sky WISE data. Astronomers sifted through images of millions of actively feeding supermassive black holes spread throughout our sky before an oddball, also known as WISE J233237.05-505643.5, jumped out.

Co-author Peter Eisenhardt, WISE project manager at NASA’s Jet Propulsion Laboratory, Pasadena, California, said that at first they thought this galaxy’s unusual properties seen by WISE might mean it was forming new stars at a furious rate, adding that on closer inspection, it looks more like the death spiral of merging giant black holes.

Radio images with the Australian Telescope Compact Array were key to identifying the dual nature of WISE J233237.05-505643.5. Supermassive black holes at the cores of galaxies typically shoot out pencil-straight jets, but, in this case, the jet showed a zigzag pattern. According to the scientists, a second massive black hole could, in essence, be pushing its weight around to change the shape of the other black hole’s jet.

The paper has been published in the Astrophysical Journal.