Powerful UFO spotted blasting from a distant black hole - Astronomy & Space - Astronomy

Artistic view of multiphase AGN-driven winds highlighting the different phases and scales that are involved in the outflow. Credit: University of Bologna

Astronomers have detected one of the most powerful ultra-fast outflows ever seen from a distant supermassive black hole. Using XMM-Newton and NuSTAR, a team studied a hyper-luminous quasar at cosmic noon and found two distinct wind components blasting away from the black hole, details of which are outlined in a paper submitted to the arXiv preprint server on June 3. The study has been submitted to the journal Astronomy & Astrophysics and is currently under minor revision.

Killer winds

Black holes consuming large amounts of material tend to lash out, driving powerful winds of gas outward from the vicinity of the accretion disk. These winds are known as ultra-fast outflows, or UFOs, when they exceed 10% of the speed of light. They are thought to be a key mechanism by which black holes regulate both their own growth and that of their host galaxies. By depositing energy into the surrounding gas, they heat it, slow star formation and can eventually quench the galaxy entirely. This kind of regulation is thought to typically take place during cosmic noon—roughly 1.6 to 3.5 billion years after the Big Bang—when both black holes and galaxies are growing at their peak rates.

UFOs leave their fingerprints in X-ray spectra as absorption features. They create dips caused by highly ionized iron in the outflowing gas absorbing X-rays as they travel toward us. Because the gas is moving outward at a significant fraction of the speed of light, these features appear shifted to higher energies than expected—a blueshift that reveals both the presence and the speed of the wind.

Most previous detections at high redshift relied on gravitationally lensed quasars—objects whose light is magnified by a foreground galaxy, boosting the luminosity. While useful, lensing can introduce some uncertainties.

UFO spotted

To study these winds in non-lensed, ordinary quasars, a team led by Giorgio Lanzuisi of INAF Bologna designed a dedicated observing program called WISSHFUL—an XMM-Newton multi-year heritage program targeting 15 hyper-luminous quasars at cosmic noon.

The first target, WISSH13, is a quasar at redshift 3.294, seen as it was roughly 2 billion years after the Big Bang. The central black hole weighs about 2 billion times the sun's mass and is feasting on matter at an exceptional rate, shining about three times brighter than astronomers would normally expect for a black hole of its mass.

In this new study, the team combined XMM-Newton and NuSTAR observations from October 2024 with an archival XMM-Newton observation from 2017 and produced a high-quality X-ray spectrum of WISSH13. It showed two clear absorption features. Modeling showed that these features arise from two different components of the same UFO, traveling at roughly 10% and 30% of the speed of light.

The spine and the sheath

The slower component was detected in both the 2017 and 2024 observations, suggesting it is a long-lived feature of the system. The faster component appeared only in the newer data, indicating it may be launched in short-lived episodes. "The detection of two distinct velocity components (∼0.1c and ∼0.3c) with different variability patterns suggests a complex, stratified outflow," the team writes.

The researchers explain that the observations are consistent with a layered wind structure predicted by theoretical models, in which a faster "spine" launched from the innermost regions of the accretion disk is surrounded by a slower "sheath" originating farther out.

Together, the two components eject around 21 and 24 solar masses of material per year, respectively. This ranks them among the most massive and powerful UFOs known. This is also the highest-redshift UFO detected from a non-lensed quasar to date.

Interestingly, despite their enormous power, the team found that the winds follow the same scaling relations observed in lower-redshift active galaxies. The team notes that future instruments, particularly the planned NewAthena X-ray observatory, will be able to identify such winds in distant quasars. 

by Shreejaya Karantha, Phys.org

edited by Gaby Clark, reviewed by Robert Egan 

Source: Powerful UFO spotted blasting from a distant black hole