Multiwavelength observations of a 2024 tidal disruption event in LEDA 145386 provide the clearest evidence yet that a spinning black hole can drag and twist spacetime — a phenomenon called frame‑dragging. X‑ray brightness oscillated every 19.6 days (by more than an order of magnitude) while radio emission varied by over four orders of magnitude, and the two bands remained synchronized. Modeling shows a co‑precessing accretion disk and jet is the simplest explanation, turning this system into a rare laboratory for testing general relativity near a ~5‑million‑solar‑mass black hole.
Star’s Death Reveals Black Hole Twisting Spacetime — Strongest Evidence Yet of Frame‑Dragging
Star's Death Plunge Reveals Spacetime Twisting Around a Black Hole
A violent stellar disruption observed in 2024 has given astronomers the clearest evidence to date that a spinning black hole can drag and twist the fabric of spacetime around it.
A Rare Laboratory for General Relativity
The phenomenon, known as frame‑dragging or the Lense–Thirring effect, was detected around the galaxy LEDA 145386, roughly 400 million light‑years from Earth. The event began in January 2024 when the Zwicky Transient Facility (ZTF) recorded a sudden brightening consistent with a tidal disruption event (TDE): a star torn apart by a supermassive black hole.
How the Signal Revealed a Twist in Spacetime
As the star’s debris formed an accretion disk and some material was launched in relativistic jets, multiwavelength monitoring uncovered an unusual, highly regular pattern. X‑ray brightness oscillated every 19.6 days, changing by more than an order of magnitude, while radio emission swung by over four orders of magnitude. Crucially, the X‑ray and radio variations were synchronized.
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Those synchronous, high‑amplitude oscillations point to a coherent precession of the disk and jet — in other words, the whole system wobbled like a spinning top. That wobble is best explained by frame‑dragging: the rotating black hole twists the surrounding spacetime and forces the inner disk and jet to precess together.
'Such cross‑band, high‑amplitude, and quasi‑periodic synchronous variability strongly suggests a rigid coupling between the accretion disk and the jet, which precesses like a gyroscope around the black hole's spin axis,' said co‑first author Yanan Wang of the Chinese Academy of Sciences.
Why This Matters
The black hole in LEDA 145386 is estimated to be about 5 million times the mass of the Sun. Frame‑dragging effects around Earth have been measured before but are extremely subtle. Around a supermassive black hole, these effects are amplified, offering a rare, natural laboratory to test general relativity in the strong‑gravity regime.
As astrophysicist Cosimo Inserra of Cardiff University put it, 'This is a real gift for physicists as we confirm predictions made more than a century ago.' Observations like these not only confirm theoretical predictions but also improve our understanding of accretion physics, jet formation, and how rotating masses generate a 'gravitomagnetic' field that influences nearby matter.
The full analysis and modeling — showing that a co‑wobbling disk and jet reproduce the observed behavior — have been published in Science Advances. These results represent one of the most compelling observational demonstrations that a black hole can drag spacetime around itself.
Quick Facts
Object: LEDA 145386 (TDE observed in 2024)
Distance: ~400 million light‑years
Black Hole Mass: ~5 million solar masses
Key Observations: 19.6‑day X‑ray oscillation (>1 order of magnitude) and radio swings (>4 orders of magnitude) in sync
