Black holes fire beams of particles, causing them to change targets over time

Black holes seem to offer astronomers endless fascination. This is at least partly due to the extreme physics going on in and around them, but sometimes it can hark back to cultural touchpoints that got them interested in astronomy in the first place.

That appears to be the case for the authors of a new paper published in The Astrophysical Journal about the movement of jets coming out of black holes. Researchers dubbed them “Death Star” black holes and used data from the Very Long Baseline Array (VLBA) and the Chandra X-ray Observatory to see where these black holes were firing jets of superheated particles. And over time, they discovered they were doing something the fictional Death Star could do: move.

The black holes at the center of the study were supermassive holes at the centers of galaxies. Importantly, they were all surrounded by hot gases that were visible to Chandra’s X-ray sensors. The jets themselves were clearly visible in the data, but there was other important information hidden within them, namely gas pockets that had been pushed away by the jets.

Each black hole has particle beams in two opposite directions. As those jets push away gas and dust, they open up a space in space around the black hole. These are visible in the X-ray data due to a lack of signal from those areas. The researchers hypothesized that the jets should align with the free space they create.

However, they found that in at least six of the sixteen black holes they studied, the beams had completely changed direction, so that the pockets of missing gas no longer aligned with the jets currently being emitted from the black hole. In some cases, these changes led to a 90-degree shift in the direction the jets were pointed.

What’s even more impressive is that they appeared to move on a relatively small time scale, with estimates ranging from 1 to 10 million years. That’s a blink of an eye for a black hole more than 10 billion years old.

So why is this important? Cosmologists theorize that these disruptive jets place an upper limit on the number of stars that form in the black holes’ host galaxy. They don’t allow the gas and dust around them to cool enough to form stars and rocky planets.

So while it’s not clear whether the jets of particles are roasting self-formed planets like the actual Death Star, it’s clear that moving the jets would cause even greater disruption to the star formation process. In theory, this would mean that galaxies with these moving jets would have fewer stars, but that’s a study for another article.

Understanding exactly why this happens may also need to be explored in another article, but the authors have a few theories. Matter orbiting and falling into the black hole can cause the black hole to rotate, causing the jets it emits to move with it.

Another explanation is that the gas moves through the galaxy without being affected by the beams. In essence, the ‘cavities’ of any gas in a galaxy are remnants of other cosmological forces and have nothing to do with the beams of black holes.

However, the authors don’t think this is likely, because the galaxy mergers that could be a source of the “sloshing” occurred in the galaxies that had moving beams and in those that did not. You would expect the voids to be present in both types if they were caused by merging galaxies rather than moving particles.

As always, there is more science to be done. Thanks to the wonderful world of video streaming, a whole generation of new scientists, inspired by the same Death Star, could do just this.