New findings about how a black hole’s energy output rises and falls
For the last 15 years astronomers have been taking the pulse of a distant black hole, watching how its energy output rises and falls. Finally, they have now confirmed a long-held suspicion that black holes collect and heat gas in a surrounding corona before spitting it out in colossal jets.
“It sounds logical, but there has been a debate for 20 years about whether the corona and the jet were simply the same thing. Now we see that they arise one after the other and that the jet follows from the corona,” says principal investigator Mariano Méndez from the Kapteyn Institute. “It was quite a challenge to demonstrate this sequential nature. We had to compare data of years with that of seconds, and of very high energies with very low ones.”
Observations of high-energy X-rays coming from the corona showed more energy than could be explained by normal heating. A possible explanation is that the black hole’s magnetic field occasionally becomes chaotic, adding energy to the corona, before becoming ordered again and ejecting the jets along its field lines.
