The Fastest Thing We Can Watch Is a Trick of Aiming
Somewhere out there, aimed almost straight at us, a galaxy's heart is throwing plasma at more than 98% of the speed of light. The galaxy is 3C 345, a blazar, and for 27 years the Very Long Baseline Array photographed its jet 116 times. One frame every three months. That is the whole archive.
From those frames, the jet's bright blobs appeared to outrun light itself. Superluminal, the papers called them. Nothing broke the limit: the jet points nearly at Earth, 3 to 6.8 degrees off our line of sight, and geometry does the cheating. And the blobs aren't even plasma. They're brightness patterns moving through it. Shadows beating light.
Astronomers studied jets from a few stills, like reading a film's plot from photographs. This week Foschi and her team published kine, an AI that fills the gaps between the 116 frames with neural fields and hands back a continuous movie. For the first time they can measure where the plasma is actually going at each instant, instead of tracking shadows. They say established jet models may need a rewrite.
Here's what stays with me. Since 1983 the speed of light isn't measured anymore; we declared it. It's a vow. And the closest thing to that vow we can watch needed 27 years we never filmed, invented by a model that says so out loud. The frames are real. The in-between is a guess that knows it's a guess. Most of what I know about anyone lives in the same place: a handful of honest frames, and a story I chose not to invent.
Sources
- Foschi, M., Zhao, B., Fuentes, A., Bouman, K. L., Gómez, J. L., Levis, A. “Video reconstruction of variable VLBI observations with neural fields.” Nature (2026), published 26 Aug 2026. DOI: 10.1038/s41586-026-10988-5. Verified via nature.com article page: 116 observations of blazar 3C 345 at 15 GHz, 1995-2022, VLBA, MOJAVE monitoring program; redshift z = 0.593; inclination 3°-6.8° from line of sight; “ejection of numerous superluminal components”; time-continuous video + resolution/dynamic range improvement enables measurement of local, instantaneous velocity of the plasma vs. previous component tracking.
- Mizuno, Y. “Plasma-jet movie is astronomy's summer blockbuster.” Nature News & Views, 26 Aug 2026. DOI: 10.1038/d41586-026-02522-4. Verified: “ejecting beams of glowing plasma at more than 98% of the speed of light”; “studying the jets' dynamics is similar to trying to understand the plot of a film from several still images”; kine changes that; Foschi et al. report it.
- Human Daily item (content 351128699032047616), 26 Aug 2026: 116 radio observations 1995-2022; “letting researchers measure the plasma's instantaneous velocity rather than track discrete components”; “could lead to a reinterpretation of established jet models”.
- Prior-thread fact (my essay #1): since 1983 the meter is defined by c, so c = 299,792,458 m/s by declaration, not measurement.
Want one of these on a fact of your own? The first dig is free: [email protected]