NASA WISE: Massive black hole duo

Two black holes are entwined in a gravitational tango in this artist's conception. 

Supermassive black holes at the hearts of galaxies are thought to form through the merging of smaller, yet still massive black holes, such as the ones depicted here. 

NASA's Wide-field Infrared Survey Explorer (WISE), helped lead astronomers to what appears to be a new example of a dancing black hole duo. 

Called WISE J233237.05-505643.5, the suspected black hole merger is located about 3.8 billion light-years from Earth, much farther than other black hole binary candidates of a similar nature. 

Credit: NASA

Astronomers have spotted what appear to be two supermassive black holes at the heart of a remote galaxy, circling each other like dance partners.

The incredibly rare sighting was made with the help of NASA's Wide-field Infrared Survey Explorer (WISE).

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.

"We think the jet of one black hole is being wiggled by the other, like a dance with ribbons," said Chao-Wei Tsai of NASA's Jet Propulsion Laboratory, Pasadena, Calif., who is lead author of a paper on the findings appearing in the Dec. 10 issue of Astrophysical Journal.

"If so, it is likely the two black holes are fairly close and gravitationally entwined."

The findings could teach astronomers more about how supermassive black holes grow by merging with each other.

The WISE satellite scanned the entire sky twice in infrared wavelengths before being put into hibernation in 2011. NASA recently gave the spacecraft a second lease on life, waking it up to search for asteroids, in a project called NEOWISE.

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.

"At first we thought this galaxy's unusual properties seen by WISE might mean it was forming new stars at a furious rate," said Peter Eisenhardt, WISE project manager at NASA's Jet Propulsion Laboratory, Pasadena, Calif., and a co-author of the study.

"But on closer inspection, it looks more like the death spiral of merging giant black holes."

Almost every large galaxy is thought to harbor a supermassive black hole filled with the equivalent in mass of up to billions of suns.

How did the black holes grow so large? One way is by swallowing ambient materials. Another way is through galactic cannibalism.

When galaxies collide, their massive black holes sink to the center of the new structure, becoming locked in a gravitational tango. Eventually, they merge into one even-more-massive black hole.

More information: Preprint paper: arxiv.org/abs/1310.2257