Scientists say two NASA space telescopes have observed a giant black hole in the act of belching out a giant flare of X-rays, providing insight into the behaviors of the mysterious cosmic objects.
While it is generally said that nothing, even light, can escape the enormously powerful gravity of a black hole, interesting phenomena such as flares can be triggered by a black hole in the regions around it.
Disks of hot, glowing material can exist in that region outside a black hole's "point of no return," known as its event horizon. As the black hole's gravity pulls gas into the region, the material heats up and shines in different wavelengths of light.
Also found near black holes are coronas, made up of high-energy particles that can generate X-ray light.
Supermassive black holes apparently can send out huge flares of X-ray light when those coronas are ejected and are launched away at nearly 20 percent the speed of light, scientists explain.
Two NASA space observatories, Swift and NuSTAR, caught such a flare being emitted from a supermassive black hole known as Mrk 335, about 324 million light years from Earth.
"This is the first time we have been able to link the launching of the corona to a flare," says Dan Wilkins at Saint Mary's University in Halifax, Canada.
"This will help us understand how supermassive black holes power some of the brightest objects in the universe," says Wilkins, lead author of a study appearing in the Monthly Notices of the Royal Astronomical Society.
Astronomers have long known about the coronas, but what causes their ejection from around a black hole is unclear, and they say they have yet to completely understand how they form and exactly what they look like.
Two possible configurations seem most likely, they say; a "lamppost" model where the coronas are compact sources of X-ray light that sit both above and below a black hole, aligned with its rotational axis, and a "sandwich" model where the coronas are more spread out and surround the black hole like slices of bread with a filling - the black hole's disk of surrounding material - in between.
The data from Swift and NuSTAR supports the "lamppost" model, researchers say, and is strong evidence of the ejection and the eventual collapse of Mrk 335's corona.
"The nature of the energetic source of X-rays we call the corona is mysterious, but now with the ability to see dramatic changes like this we are getting clues about its size and structure," says Fiona Harrison, NuSTAR principal investigator at the California Institute of Technology in Pasadena, Calif., who was not involved in the published study.
