Astronomy's other ‘UFO’ is a quasar wind moving at 0.3c

Researchers analyzed simultaneous 2024 observations of the luminous quasar PDS 456 from the XRISM and NuSTAR X-ray observatories. Their preprint models a variable, partially covering, low-ionization ultra-fast outflow moving at about thirty percent of light speed and places it at least roughly 4,000 gravitational radii from the central black hole.

In this branch of astronomy, ‘UFO’ means ultra-fast outflow: extremely energetic gas expelled from the region around an active galactic nucleus. The authors use changes in the X-ray absorption to test how that wind may be accelerated, favoring radiation pressure or compact magnetic processes over one self-similar wind model. The work is a submitted preprint and has no evidentiary relationship to unidentified anomalous phenomena.

Why it matters

Clear terminology prevents a spectacular but conventional astrophysical acronym from becoming another misleading search result—and the underlying black-hole physics is genuinely remarkable on its own.

What the source establishes

Confirmed current astrophysics preprint and reported model parameters. ‘UFO’ here means ultra-fast outflow, not an unidentified flying object; peer review remains pending.