It’s not the kind of thing astronomers expect to see while observing the powerful effects of a distant supermassive black hole: an unprecedented UFO sighting.
However, that’s precisely what one group of scientists now reports in a preprint paper, who detail the successful detection of one of the strongest UFOs—a black hole phenomenon otherwise known as “ultra-fast outflows”—that astronomers may have ever seen.
The landmark detection was made possible with the XMM-Newton space observatory and NuSTAR X-ray telescope, which allowed the researchers behind the discovery to observe a luminous quasar with origins that date back to “cosmic noon,” revealing a pair of outflow wind components being blasted from the black hole in question.
Cosmic Monsters with Major Appetites
Black holes have more than just large appetites for cosmic material: they also produce significant gas-driven winds from around their accretion disk.
These winds become known as ultra-fast outflows (UFOs) when their strength propels them to greater than ten percent of light speed, and astronomers currently believe they are an important part of what helps black holes regulate their growth, which may also hold for their host galaxies.
One way this occurs is that UFOs help to heat galactic gases that give rise to star formation, a quenching process that most astronomers believe occurred during a period called “cosmic noon,” which occurred between 1.6 and 3.5 billion years after the birth of the universe.
Cosmic Fingerprints of Powerful UFOs
Astronomers can detect ultra-fast outflows based on the “dips” they create in their powerful gusts, which are caused by ionized iron present in their outflow gases. These gases also absorb X-rays along their path away from their black hole originators, which leave “fingerprints” in the form of absorption features that are detectable using X-ray telescopes.
Significantly, these “dips” manifest as a blueshift since they are shifted to higher energies as they move at such high speeds (again, roughly 10% of the speed of light). From the blueshifted energy signatures they comprise, astronomers can determine not only the presence of UFOs, but also the wind speed of their gusty outflows.
In the past, most detections of these high-powered cosmic phenomena have relied on gravitationally lensed quasars. These celestial objects occur when a galaxy or similar feature closer to Earth appears in front of them, magnifying the quasar’s light and significantly brightening its luminosity from our Earthly perspective.
However, lensing of this variety can also present problems, and so astronomers led by Giorgio Lanzuisi of INAF Bologna designed a special system to target more than a dozen hyper-luminous quasars at cosmic noon, as a means of getting a better feel for the dynamics of non-lensed quasars.
“WISSHFUL” Thinking
WISSHFUL is an XMM-Newton multi-year heritage program that Lanzuisi and his colleagues designed for this purpose, whose initial target became a quasar designated WISSH13, whose redshift at 3.294 marks the object’s existence as it appeared approximately 2 billion years after the Big Bang.
WISH13’s black hole also weighs in at close to 2 billion times that of our Sun, which causes it to shine far brighter than normally expected for an object of its estimated mass.
Their work began in the autumn of 2024 by combining observations from XMM-Newton and NuSTAR initially obtained in 2017. From these X-ray images of WISSH12, a pair of distinctive absorption features became evident, which the team determined to have been generated by two separate sources from within the same ultra-fast outflow.
These components were found to travel at different speeds: one moving at close to 30% of the speed of light, while the other at only about 10% of light speed. The slower of these two appears to have been an enduring component of the UFO, while the faster one showed signatures that indicated a more recent appearance. This could mean that it emanates from events that are shorter in duration.
By matching theoretical predictions of a layered wind structure surrounding the black hole, the researchers say their observations align with models that indicate a fast-moving inner “spine” launched from the accretion disk’s innermost regions. Meanwhile, a slower outer “sheath” is also believed to emanate farther from the black hole. The combined outflow components produce an estimated 21 to 24 solar masses of material annually.
The Most Massive UFO Ever Observed?
Such figures, the team says, represent what is believed to be among the most massive and energetic ultrafast outflows ever observed, a discovery which also marks the highest-redshift ultrafast outflow yet detected in a non-lensed quasar.
Despite their remarkable energetic output, the team says these outflow winds seem to conform to the same essential relationships observed in active galaxies much closer to Earth, suggesting that the processes driving these outflows have remained remarkably consistent across cosmic time.
Going forward, the team says they hope to make additional observations of these powerful cosmic phenomena with help from the new Athena X-ray mission, which they say could help uncover similar winds in even more distant quasars.
The team’s discoveries were detailed in a recent paper, “The WISSHFUL program: the highest redshift UFO discovered in a non-lensed QSO,” which appeared at the preprint arXiv.org server.
Micah Hanks is the Editor-in-Chief and Co-Founder of The Debrief. A longtime reporter on science, defense, and technology with a focus on space and astronomy, he can be reached at micah@thedebrief.org. Follow him on X @MicahHanks, and at micahhanks.com.