Move Over, Gravity: Black Hole Magnetic Fields May Have Powerful Pull

It’s oft-repeated that black holes are powerful gravity wells, because they represent a dense concentration of matter in one location. But what about their magnetic fields? A new study suggests that this force could be at least as strong as gravity in supermassive black holes, the singularities that lurk in the center of many galaxies.

Simulations of magnetic fields of gas falling into these beasts suggest that this action — if the gas carries a magnetic field — makes the field stronger until it equals gravity.

Magnetic fields can affect properties such as how luminous black holes appear (in radio) and how powerful the jets emanating from the singularity are. The scientists speculate that when you see bright jets from a black hole, this could imply a strong magnetic field indeed.

“Surprisingly, the magnetic field strength around these exotic objects is comparable to the magnetic field produced in something more familiar: a magnetic resonance imaging (MRI) machine that you can find in your local hospital,” the Max Planck Institute for Radio Astronomy stated.

“Both supermassive black holes and MRI machines produce magnetic fields that are roughly 10,000 times stronger than the Earth’s surface magnetic field, which is what guides an ordinary compass.”

New information on how strong the magnetic fields was based on recent work with the Very Long Baseline Array, a networked group of radio telescopes in the United States. Specifically, the information came from a program named MOJAVE (Monitoring Of Jets in Active galactic nuclei with VLBA Experiments) that looks at jets around several hundred supermassive black holes.

The researchers emphasized that more observational research will be needed to supplement the simulations. The work will be published today in Nature. Leading the research was Mohammad Zamaninasab, a past researcher at Max Planck.

Source: Max Planck Institute for Radio Astronomy