(ORDO NEWS) — Astronomers using the Karl G. Jansky Very Large Array (VLA) radio observatory of the US National Science Foundation have shown that in a jet of material observed from the nucleus of a giant galaxy, material moves along channels formed by a magnetic field with a “corkscrew” structure at a distance nearly 3,300 light-years from the galaxy’s central supermassive black hole (SMBH).
“By taking high-quality images of Messier 87 (M87) with the VLA at different wavelengths, we were able to reveal the three-dimensional structure of the magnetic field in this jet for the first time,” said Alice Pasetto of the National Autonomous University of Mexico, who led the group. “The material of this jet forms a double helix, which bears a resemblance to the DNA helix.”
M87 is a giant elliptical galaxy located about 55 million light-years from Earth. A supermassive black hole with a mass of about 6.5 billion times the mass of the Sun is located in the center of this galaxy. This black hole became the first of its kind “Instagram star” – hitting the world’s first images of a black hole taken by the Event Horizon Telescope (EHT) collaboration and published in 2019. Earlier this year, new images from this international collaboration allowed tracing the structure of the magnetic fields in the vicinity of the event horizon of this black hole.
Pasetto and her colleagues used the VLA observatory to figure out the details of the structure of the magnetic field by studying its polarization, or the orientation of radio waves emitted from the direction of this magnetic field, as well as measuring the strength of the magnetic field in different parts of the jet. These observations, carried out using the most powerful VLA telescope configuration, providing the highest image resolution, provided very detailed images of the jet structure.
“We expected to see spiral magnetic fields in the immediate vicinity of the black hole, and we assumed that these fields play an important role in the transport of material along the channels within the boundaries of the narrow jet, but we did not expect to see such a powerful spiral magnetic field at such a great distance.” – said Jose M. Marti from the University of Valencia, Spain
According to the authors, the increased power of the spiral magnetic field at a great distance from the black hole of the M87 galaxy may be associated with the instability of the jet material flow, which has an ordering effect on the magnetic field The work was published in the Astrophysical Journal Letters.
Contact us: firstname.lastname@example.org