image: Morphological structure of the galactic outflow in VV 340a. This artistic rendering illustrates a multi-phase galactic outflow driven by a central active galactic nucleus. The white helix represents a precessing radio jet, a rotating beam of high energy plasma launched from the magnetosphere of the central supermassive black hole. The red filaments represent highly ionized coronal gas which results from the collision of the jet with the ambient gas of the host galaxy. The blue filaments represent ionized gas being ejected from the galaxy at high speeds and extending up to 15 kiloparsecs. As the jet propagates outward, it energizes and propels the galaxy’s gas into a high velocity outflow, altering the galaxy’s future evolution.
Credit: W. M. Keck Observatory/Adam Makarenko
Active galactic nuclei, energetic and luminous regions powered by an accreting supermassive black hole at the center of some galaxies, can launch a jet that drives a gas outflow, shaping star formation in their host galaxy. Justin Kader and colleagues have observed this phenomenon in the nearby active galaxy VV 340a. Kader et al. observed the jet and galaxy across infrared, optical, radio, and sub-millimeter wavelengths, using the James Webb Space Telescope, Keck-II telescope, the Jansky Very Large Array and the Atacama Large Millimeter/submillimeter Array. The researchers combined these observations with modeling, to show that the low-power radio jet emitted by VV 340a undergoes a conical wobble, known as precession, as it moves outward. The jet ionizes and ejects gas as it propagates away from the supermassive black hole, driving a gas outflow at a rate of 19.4 ± 7.9 solar masses per year. This outflow rate is large enough to affect the star formation rate of the host galaxy, Kader et al. conclude.
Journal
Science
Article Title
A precessing jet from an active galactic nucleus drives gas outflow from a disk galaxy
Article Publication Date
8-Jan-2026