M87: independent reanalysis recovers the black hole's ring
· BehindLines newsroom
The first image of a black hole, published in 2019, has withstood an independent check. A team reanalysed data from the Event Horizon Telescope (EHT) radio-telescope network and recovered the original bright ring, according to a paper published on 11 November 2026 in the journal Nature, covered by Nature and by The Register.
A doubt lingering since 2022
According to Nature, the image of the shadow of the supermassive black hole in the middle of galaxy M87 relied on data captured simultaneously by radio telescopes spread across several continents. The reconstruction is very difficult: in principle it offers the sharpness of one radio dish whose diameter matches Earth's. The image showed a bright ring around a darker central disk, consistent with models based on Einstein's general relativity. But from 2022, Junichiro Makino of Kobe University and colleagues challenged those conclusions. By slightly changing the assumptions of a method the EHT had used, they obtained a glob of radio emission rather than a ring, Nature reports.
An independent method
The Register explains that four Australian researchers built their own imaging algorithm, based on machine learning. Samuel Lai, a postdoctoral fellow at CSIRO in the west of Australia, carried out this work with his team. Their approach relies on "closed triplets", which use three telescopes to correct errors, rather than on pairs of stations. The original measurements came from eight telescopes spread around the world, the outlet notes. According to The Register, the new result reproduces the 2019 ring. Lai says his model did not know what a black hole looks like and calls this a first genuinely independent validation of the EHT image. According to Nature, the results, which include new images, largely corroborate the original findings.
What the EHT says
EHT director Laurent Loinard finds it "extremely gratifying" that an independent method recovers the ring structure over several years, matching the collaboration's published results very closely, as quoted by The Register.
Why it matters
For Samuel Lai, this validation is an important step in the scientific process. According to Nature, the results largely corroborate the EHT's original conclusions. Because the Nature page we could read was truncated, we do not detail the method or any caveats the authors may have.