Centaurus A's Warped Magnetic Fields
Image Credit:
Optical: European Southern Observatory (ESO) Wide Field Imager;
Submillimeter: Max Planck Institute for Radio Astronomy/ESO/Atacama Pathfinder Experiment (APEX)/A.Weiss et al;
X-ray and Infrared: NASA/Chandra/R. Kraft; JPL-Caltech/J. Keene;
Text: Joan Schmelz
(USRA)
When galaxies collide -- what happens to their
magnetic fields?
To help find out, NASA pointed
SOFIA, its flying 747,
at galactic neighbor
Centaurus A
to observe the emission of polarized dust -- which traces magnetic fields.
Cen A's unusual shape results from the clash of two galaxies with
jets powered by gas accreting onto a
central supermassive black hole.
In the resulting
featured image, SOFIA-derived magnetic streamlines are superposed on
ESO
(visible: white),
APEX
(submillimeter: orange),
Chandra
(X-rays: blue), and
Spitzer
(infrared: red) images.
The magnetic fields were found to be
parallel to the
dust lanes on the outskirts of the
galaxy but distorted near the center.
Gravitational forces near the
black hole accelerate ions and enhance the
magnetic field.
In sum, the collision not only combined the galaxies’ masses -- but amplified their magnetic fields.
These results
provide
new insights into how magnetic fields evolved in the
early universe when
mergers were more common.