The researchers, led by astrophysicist David Garofalo at NASA's Jet Propulsion Laboratory, said their finding has broad implications for how galaxies change over time.
"A lot of what happens in an entire galaxy depends on what's going on in the minuscule central region where the black hole lies," Garofalo said, explaining black holes can spin in the same direction as their disks, called prograde black holes, or against the flow , called retrograde black holes. For decades, astronomers thought that the faster the spin of the black hole, the more powerful the jet. But there were problems with that "spin paradigm" model. For example, some prograde black holes had been found with no jets.
"Garofalo and his colleagues have been busy flipping the model on its head," said NASA. "In previous papers, they proposed that the backward, or retrograde, black holes spew the most powerful jets while the prograde black holes have weaker or no jets."
The new study links the researchers' theory with observations of galaxies across time, or at varying distances from Earth.
The research that included Daniel Evans of the Massachusetts Institute of Technology and Rita Sambruna of NASA's Goddard Space Flight Center appears in the May online issue of the Monthly Notices of the Royal Astronomical Society.