New black hole jet observations challenge a leading theory on the mysterious phenomenon

Data from the Chandra X-ray Observatory could dispel a widely-held belief about black hole jets.
Chris Young
An artist's impression of a black hole firing a jet into space.
An artist's impression of a black hole firing a jet into space.

NASA / JPL-Caltech 

A new study has seemingly ruled out a leading theory on how black hole jets accelerate particles to the point they emit X-rays far and wide throughout the cosmos.

The paper, published in the journal Nature Astronomy, presents a new hypothesis for how particle acceleration works in black hole jets, shedding light on the mysterious phenomena.

Reassessing the behavior of black hole jets

One leading model for describing particle acceleration in black hole jets describes x-ray emissions from these jets as remaining stable over the course of millions of years. However, the new paper shows how the X-ray emissions of a number of jets varied over just a few years.

"One of the reasons we're excited about the variability is that there are two main models for how x-rays are produced in these jets, and they're completely different," lead author Eileen Meyer, an astronomer at University of Maryland, Baltimore County, explained in a press statement.

"One model invokes very low-energy electrons and one has very high-energy electrons. And one of those models is completely incompatible with any kind of variability."

The new paper's authors analyzed archival data from the Chandra X-ray Observatory and found frequent variability among the 53 jets captured by the observatory. Discovering this frequent variability on short time scales "is revolutionary in the context of these jets because that was not expected at all,” Meyer said.

The same theory that assumes stability in X-ray emissions over millions of years also assumes that particle acceleration occurs within the black hole that's emitting the jet. However, the new study found changes in X-ray emissions along the entire length of the jets and far from the black hole.

Shedding new light on cosmic phenomenon

Ultimately, the team found that between 30 and 100 percent of the jets in the study showed variability over short time scales. "While we would like better constraints," Meyer said, "the variability is notably not zero."

The new findings call into question one of the leading theories for the mechanisms of black holes firing massive jets into space. We know that black holes propel these massive energetic jets of material from their rings or accretion discs, but we don't quite yet understand how or why.

The latest study on the subject and cutting-edge new images of black hole jets should hopefully allow the scientific community to narrow the possibilities down just a little further.

Add Interesting Engineering to your Google News feed.
Add Interesting Engineering to your Google News feed.
message circleSHOW COMMENT (1)chevron
Job Board