A neighboring galaxy has been observed actively depleting its reserves of stellar fuel, with extensive plumes of incandescent plasma being expelled from the colossal singularity at its galactic center.
This celestial entity, identified as VV 340a, affords a remarkable opportunity to witness a mechanism by which black holes can suppress the genesis of stars within their host galaxies, from a comparatively intimate proximity of approximately 500 million light-years. According to scientific analyses, the black hole resident in VV 340a is expelling such a prodigious volume of matter that the rate of new star creation is demonstrably impacted.
“To our understanding, this marks the inaugural instance of a kiloparsec-scale, or galaxy-wide, precessing radio jet initiating a substantial outflow of coronal gas,” states astrophysicist Justin Kader, affiliated with the University of California, Irvine.
“Its operative function is to substantially impede the stellar formation process within the galaxy by elevating the temperature of, and expelling, the gas essential for star birth.”
While supermassive black holes are considered fundamental components in galactic evolution, they are also capable of emitting such intense radiation that they effectively deprive galaxies of the necessary constituents for generating new stars. The cessation of galactic activity is not necessarily an irreversible condition, but it does signify the conclusion of a galaxy’s energetic, incandescent, and nascent epochs.
Black holes can halt star formation through a variety of processes, collectively termed ‘feedback’, which are precipitated by the black hole’s activity: potent jets, radiative pressure, and outflows generated as the black hole voraciously consumes matter at extraordinary velocities.
Jets are immense structures that emanate from the poles of an actively accreting black hole. The black hole assimilates vast clouds of gas and dust that spiral inward to form a disk surrounding the ravenous object; however, not all of this material ultimately crosses the event horizon.
While the precise details remain somewhat enigmatic to astronomers, it is theorized that a portion of the infalling matter is diverted from the inner periphery of the accretion disk and accelerated along the black hole’s magnetic field lines beyond the event horizon. Upon reaching the polar regions, this material is propelled into space at phenomenal speeds, occasionally achieving a significant fraction of the speed of light.
Over extended periods, this expulsion can engender structures (jets) that span millions of light-years. The jets emanating from VV 340a have not traversed space for such durations; they extend approximately 20,000 light-years in opposing directions from the black hole, saturated with shock-heated, ionized plasma.
Nevertheless, these represent the most extensive and voluminous jets composed of shock-heated, highly ionized coronal gas—material heated to temperatures akin to the Sun’s outer atmosphere—ever to be detected.
“In other galactic systems, this type of highly energetic gas is typically confined to within tens of parsecs from a galaxy’s central black hole, and our finding surpasses typical observations by a factor of 30 or more,” Kader elucidates.
A salient observation is that VV 340a’s jets, while extensive, are not exceptionally forceful in the context of astrophysical jets.
Despite this, they appear to be systematically siphoning an annual mass equivalent to approximately 19.4 solar masses from the galaxy. For comparative context, the Milky Way generates an annual stellar mass of up to around 3.3 solar masses.
The geometric configuration of VV 340a’s bipolar jet may be intricately linked to the efficiency with which star-forming material is being evacuated from the galaxy. The jet exhibits precession, meaning its rotational axis wobbles, analogous to a rotating sprinkler head. This characteristic imparts a helical rather than linear form to the jet.
The research team posits that, as they are expelled, VV 340a’s helical jets interact with the galactic gas, drawing it along and heating it to coronal temperatures at radial distances from the black hole previously unobserved.
Furthermore, helical precessing jets are typically observed in more mature galaxies. VV 340a, however, is comparatively young and is undergoing a merger with another galaxy. This discovery suggests that even galaxies exhibiting youthful characteristics can experience feedback episodes in unforeseen ways.
Given that VV 340a is in the process of merging with another galaxy, any suppressive effect on its star formation rate is unlikely to be enduring. Galactic mergers frequently instigate a phase of heightened star formation, as the stellar material from each galaxy becomes compressed and disturbed, creating optimal conditions for a significant wave of star birth.
“Our understanding of the prevalence of this type of activity is still in its nascent stages,” remarks astronomer Vivian U of Caltech.
“We are eager to continue investigating such unprecedented phenomena across diverse physical scales of galaxies, utilizing data from advanced observational instruments,” including the JWST, she adds.
“We eagerly anticipate further revelations.”
This groundbreaking discovery has been thoroughly documented in the esteemed scientific journal Science.
